UHV Flanges and Fittings - VG Scienta

UHV Flanges and Fittings 

Item Page 

Introduction to Conflat Flanges ............................................... 030 

Metric Conflat Flanges ................................................................ 035 

Metric Conflat Quick Comparison Chart ............................ 036 

304L Fixed Bored Flanges ........................................................ 037 

304L Rotatable Bored Flanges ................................................. 038 

304L Fixed Blank Flanges ........................................................... 039 

304L Rotatable Blank Flanges ................................................... 040 

316LN Fixed Bored Flanges ...................................................... 041 

316LN Rotatable Bored Flanges .............................................. 042 

316LN Fixed Blank Flanges ....................................................... 043 

316LN Rotatable Blank Flanges .............................................. 044 

Double-sided Flanges 304L and 316LN .................................. 045 

Zero Length Adaptor Flanges ................................................. 046 

Klein to Conflat Adaptors ......................................................... 047 

Accessories .................................................................................... 048 

Imperial Conflat Flanges ............................................................. 051 

Imperial Conflat Quick Comparison Chart ........................... 052 

304L Fixed Bored Flanges ........................................................ 053 

304L Rotatable Bored Flanges ................................................. 054 

304L Fixed Blank Flanges ........................................................... 055 

304L Rotatable Blank Flanges ................................................... 056 

316LN Fixed Bored Flanges ...................................................... 057 

316LN Rotatable Bored Flanges .............................................. 058 

316LN Fixed Blank Flanges ........................................................ 059 

316LN Rotatable Blank Flanges ................................................ 060 

Double-sided Flanges .................................................................. 061 

Zero Length Adaptor Flanges ................................................... 063 

Klein to Conflat Adaptors ......................................................... 064 

Accessories .................................................................................... 065 

Gaskets ........................................................................................... 069 

Copper Gasket Ranges ............................................................... 070 

Silver Plated Gaskets ................................................................... 074 

Viton ® Gaskets ............................................................................. 075 

Aluminium Gaskets...................................................................... 076 

Item Page 

UHV Fittings .................................................................................. 077 

UHV Tubulated Flanges .............................................................. 079 

UHV Straight Connectors ......................................................... 080 

UHV Curved Elbows................................................................... 081 

UHV Mitred Elbows .................................................................... 082 

UHV Flexible Connectors ......................................................... 083 

UHV Tees ...................................................................................... 086 

UHV 4-Way Crosses .................................................................. 087 

UHV 6-Way Crosses .................................................................. 088 

Accessories .................................................................................... 089 

UHV Cluster Flanges .................................................................. 090 

Custom Hardware ....................................................................... 091 

029

UHV 

Flanges 

Conflat Flanges 

From Commercial Grade 304L to High 

Quality 316LN stainless steel 

VG Scienta is probably the only manufacturer to 

offer a range of flange material grades throughout 

the entire product range, to cover both the 

standard and high performance requirements 

of UHV technology. With commercial 304L 

and 316LN stainless steels it is possible to cover 

the operational temperature range of -190 ºC 

to +450 ºC. This can be extended when using 

vacuum firing to +950 ºC with our standard 

316LN grade of flange material. All flanges 

are manufactured on dedicated CNC machines 

to ensure excellent product consistency. Every 

stage of production is carefully quality controlled 

to ISO9001 specifications and each flange 

is code stamped with a material cast number 

to allow full material traceability. Each flange is 

processed through an automated aqueous cleaning 

procedure and individually sealed and packed 

so that the product is in perfect condition for 

use on UHV equipment. 

VG Scienta’s standard range of flanges (ZFC 

and ZFCR series) are manufactured from specially 

selected commercial grade 304L steel of 

high cleanliness and carefully controlled chemistry. 

These flanges are suitable for the every 

day vacuum user who wants a reliable, but cost 

effective, UHV material. 316LN flanges on the 

other hand (ZFCL and ZFCRL series) are specially 

produced for more demanding applications 

including the need for greater hardness (at high 

temperatures) and low magnetic permeability. 

This grade of austenitic stainless steel has nitrogen 

added, increasing the overall hardness and 

strength. Hardness value of 316LN is typically 

160-180 Brinell and generally higher than 304 

series steels. More importantly, 316LN retains 

the hardness at elevated temperatures, especially 

after repeated bakeouts or high temperature system 

degassing procedures. 

The 316LN steel is electroslag refined (ESR) to 

eliminate gross macro segregation and improve 

grain homogeneity resulting in an excellent uniform 

structure. The ESR process substantially 

reduces the total inclusion content and removes 

impurities, producing a very clean material. This 

minimises any risk of leakage paths due to inclusions. 

316LN steel produced by this route is 

virtually ferrite free and flanges produced from 

this material have a very low magnetic permeability 

(

Why Two Materials? 

It is important to note that there are several 

grades of material available in the market place. 

In increasing order of cost, these materials are: 

1 Flame cut flange blanks (the part used before 

it is machined into a flange) are cut with an 

industrial laser or similar from large sheets of 

rolled stainless steel. 

2 Forged flange blanks are made from individually 

forged pieces of stainless steel. It has the 

same basic properties as flame cut. 

3 Cross forged flange blanks are made from 

individually forged pieces of stainless steel, 

they are then forged in several directions to 

break up any microscopic stingers (formed 

during manufacture of the billet) that may be 

present. This process is now only used for the 

316LN material. Advances in steel manufacture 

have meant that this is no longer such a 

significant problem as it was 20 years ago. 

316LN Flanges - Material Certification 

A commonly asked question about 316LN relates 

to the various levels of certification that we can 

supply. 

There are two levels of certificates that we can 

provide: 

1 Certificates of Conformity (C of C's) 

These are issued internally by VG Scienta and 

effectively qualify that the item in question 

conforms to our published specification. i.e. 

it is made from 304L stainless steel, or it can 

be baked to 250 ºC etc. 

These Certificates of Conformity can apply 

to items other than just flanges. As regards 

the actual stainless steels involved in the 

manufacture of our flanges, we can also provide 

(at extra cost) the following additional 

certification. 

2 Material Certificates 

When the stainless steel is manufactured, a 

chemical analysis of the resultant material is 

performed, and samples are taken from the 

top, the middle, and the bottom of the ingot 

and averaged to give the figures. The cast is 

www.vgscienta.com 

Conflat Flanges 

individually numbered and is identified by 

this number. These certificates are available 

to customers for a small charge as they are 

normally supplied with the material. This 

certificate tells you what different chemicals 

are present in the steel and what mechanical 

properties the steel has. 

Typical 316LN Chemical Composition % 

Cr 16.0 to 18.5 % Ni 12.0 to 14 % 

C < 0.03 % Si 0.7 to 1.0 % 

Mn 1.5 to 2.0 % Mo 2.0 to 3.0 % 

N 0.14 to 0.20 % P 0.045 % max 

S 0.030 % max 



031



Basic Flange Types 

Blank Flange Blank Rotatable 

Bored Bored Rotatable 

Stepped Adaptor Zero Length Adaptor 

032 www.vgscienta.com

FC Flanges - 304L and 316LN Features 

and Benefits 

• Made to international flange standards. Fits 

to customers existing flange dimensions 

• Two materials available, 304L and 316LN 

• Quick delivery - extensive stock 

• High quality control 

• Competitive prices 

• Wide range of sizes and types suitable for 

all customer requirements 

• Low outgassing rates. Rapid achievement 

of UHV, 316LN can be vacuum fired to 

remove dissolved (i.e. H 2 ) gases in the flange 

material 

• Controlled material hardness. Longer life 

• High temperature range. Suitable for use 

from liquid nitrogen temperatures to 

450 °C. 316LN to 1.050 °C vacuum bake 

• Good pressure range. 1 Bar to 10e -12 mbar 

• Outgassing rates



Conflat Flanges - Important Product Information 

IMPORTANT PRODUCT INFORMATION 

VG Scienta have been manufacturing Conflat flanges 

for over 40 years and were one of the first suppliers 

to the UHV industry. We have a very wide range of 

sizes and types of flanges produced in a number of different 

materials. These are fully compatible with other 

manufacturers' flanges up to NW250 size in terms of 

mating flanges together - thicknesses (dimension B in 

the drawing), gasket sizes, bolt hole number, pitch circle 

diameter (or PCD, dimension F in the drawing) and size 

etc., but there are some features of our flanges that you 

should be aware of when consulting this catalogue and 

ordering our products 

NW versus FC Designations 

VG Scienta has evolved and used its own FC designation to describe flange sizes. It is important to note that FC 

designation is not the same as the NW designation. FC generally refers to the outside diameter (OD) of a tube 

that is fitted to a flange; NW generally refers to the inside diameter (ID) or “clear bore” of the flange. 

Thus a VG Scienta FC41 flange has a clear bore of 38 mm and is therefore equivalent to an NW38 flange. 

Tube sizes - Imperial versus Metric Tube 

The tube counterbore diameters (dimension D in the drawing) of our flanges have been primarily governed by the 

availability of Imperial (inch) size tube in the UK; the USA still works with Imperial units and many of the original 

UK tube sizes are still used in the USA. 

In many cases there are standard sizes of metric tube that will fit our standard flanges - all critical dimensions of our 

standard flanges are quoted in millimetres, so please ensure that you check the tube counterbore diameter before 

ordering. In some cases we have included “true metric” versions of our flanges in the flange tables; otherwise the 

availability of metric versions is indicated against each flange part code. 

Tube Counterbore Depth or “Land Thickness” 

The land thickness (dimension C in the drawing) or set-back dimension is effectively the distance between the end 

of the tube that you insert into the flange, and the front face of the flange. For example, if you are fitting flanges to 

port tubes on a chamber, then this is the dimension that you need to take into account when calculating the overall 

port lengths. 

This dimension is not constant for all flanges, and varies from manufacturer to manufacturer. It is very important to 

take note of this when ordering bored flanges. 


Introduction to Conflat Flanges 

• Wide range of Imperial and Metric standard 

sizes 

• All flanges manufactured on computer 

controlled CNC machines for accuracy 

• Available in 304L or 316LN stainless steel 

• Low outgassing rates, 450 °C) without 

leaking. 

VG Scienta’s range of UHV flanges is world 

renowned both for its quality and range of sizes 

and materials. The complete range of flanges are 

fully compatible with the internationally agreed 

ISO/Pneurop standards and will connect to any 

other flange that also complies with this standard 

(for flanges with a diameter greater than 

300 mm no such standards exist at present). All 

flange OD dimensions are nominal. 

Method of Sealing 

The UHV seal is made by trapping a copper gasket 

between two sexless flanges that have a sharp 

knife-edge profiled onto their operating face. 

When joined together with a set of connecting 

bolts, the knife-edges cut into the surface of the 

copper gasket to make a seal that is UHV leak 

tight. When exposed to bakeout temperatures 

the shape of the knife-edge ensures that the seal 

remains leak tight by resisting any differential 

movements between the copper gasket and the 

stainless steel flange parts. 


Metric Conflat Flanges 

Fixed and Rotatable Flanges 

To aid the construction of UHV chambers and 

components, VG Scienta flanges are available in 

both fixed and rotatable configurations. Fixed 

flanges are a single machined item with the 

bolt hole orientation fixed into position once 

they are welded onto a chamber or component. 

Rotatable flanges are manufactured in two parts 

with the knife-edge part and external bolt hole 

ring being separate. Once the knife-edge part is 

welded in position it is easy to change the orientation 

of the bolt holes relative to the axis of the 

port. This makes rotatable flanges ideal for the 

situations where alignment of a component to 

a chamber (or another component) needs to be 

set accurately before the flange mounting bolts 

are tightened. 

Please Note: It is not advisable to have two 

rotatable flanges at the same joint. 

Internal Weld 

Copper Gasket 

Flanges are bolted together with a copper 

gasket between the knife edges. 

Metric 



035

Metric 



Metric Conflat Flange Quick Reference Comparison 

Chart 

Metric Flange Comparison Chart 


See page 034 concerning FC and NW designations 

304L 304L 304L 304L 316LN 316LN 316LN 316LN 

OD Pneurop Fixed Rotatable Fixed Rotatable Fixed Rotatable Fixed Rotatable 

mm inch Equivalent Bored Bored Blank Blank Bored Bored Blank Blank 

34 1.33 Blank ZFC90 ZFCR90 ZFCL90 ZFCRL90 

34 1.33 Blank ZFC90T ZFCL90T 

34 1.33 NW7CF ZFC97 ZFCR97 ZFCL97 ZFCRL97 

34 1.33 NW12CF ZFC912 ZFCL912 



34 1.33 NW16CF ZFC19NS ZFCL19NS 

34 1.33 NW16CF ZFC19NST ZFCL19NT 


70 2.75 Blank Tapped ZFC2T ZFCR2T ZFCL2T ZFCRL2T 


70 2.75 NW14CF ZFCR14T ZFCRL14T 


70 2.75 NW25CF ZFCR25T ZFCRL25T 


70 2.75 NW35CF ZFC38T ZFCR38T ZFCL38T ZFCRL38T 



70 2.75 NW45CF ZFC45 ZFCL45 

70 2.75 NW45CF ZFC45T ZFCL45T 

85 3.38 Blank ZFC3 ZFCL3 

85 3.38 Blank Tapped ZFC3T ZFCL3T 













152 6.00 NW100CF ZFC100T ZFCR100T ZFCL100T 






254 10.00 Blank Tapped ZFC10T ZFCL10T 



Please Note - No accepted international standard dimensions exist for flanges with an OD of 300 mm or greater. 

300 12.00 Blank ZFC12 ZFCL12 

300 12.00 NW250CF ZFC250 ZFCL250 

362 14.25 Blank ZFC1425 ZFCL1425 

362 14.25 NW300CF ZFC300 ZFCL300 

indicates clearance bolt holes indicates tapped bolt holes 


Fixed bored flanges are available in the full range 

of sizes as indicated in the chart below. They 

are normally welded on to chamber tubulations 

or certain specific sizes of component. Please 

note that the smaller sizes of flange can accept a 

number of different standard tube sizes. 

(1) Dimension D refers to external tubulation and not the recess in 

flange body as per rest of range of flanges 

(2) Non spigotted flange 

(3) Non spigotted flange and tapped holes 

(M) Metric version available on request. Contact Technical Sales 

Department for details. 

(T) Tapped version available on request. Contact Technical Sales 

Department for details. 


304L Fixed Bored Flanges (FC Series) 

304L Fixed Bored Flanges 

Tube Bolt Bolt Tube Size 

Clear Flange Land Counter Hole Hole No. of to Fit Shipping 

OD Pneurop Bore Thickness Thickness Bore PCD Diameter Bolt Flange Weight 

mm inch Equivalent A B C D F (or thread) Holes Bore kg Order Code 

34 1.33 NW7CF 6.4 7.6 N/A 6.4 27.0 4.3 6 6.35 0.1 ZFC97 (T) 

34 1.33 NW12CF 12.0 7.6 N/A 12.7 27.0 4.3 6 12.70 0.1 ZFC912 (T) 

34 1.33 NW14CF 13.2 7.6 4.8 14.4 27.0 4.3 6 14.29 0.1 ZFC914(T) 

34 1.33 NW16CF 16.6 7.6 12.7 19.1 27.0 4.3 6 19.05 0.1 ZFC919 (1)(T)(M) 

34 1.33 NW16CF 16.6 7.6 4.8 19.1 27.0 4.3 6 19.05 0.1 ZFC19NS (2) 

34 1.33 NW16CF 16.6 7.6 4.8 19.1 27.0 (M4) 6 19.05 0.1 ZFC19NST (3) 

70 2.75 NW14CF 13.2 13.0 4.8 14.4 58.7 6.8 6 14.29 0.3 ZFC14 

70 2.75 NW25CF 24.2 13.0 4.8 25.5 58.7 6.8 6 25.40 0.3 ZFC25 (T) 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 58.7 6.8 6 38.10 0.3 ZFC38 (M) 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 58.7 (M6) 6 38.10 0.3 ZFC38T (M) 

70 2.75 NW40CF 40.0 13.0 4.8 41.3 58.7 6.8 6 41.27 0.3 ZFC41 

70 2.75 NW40CF 40.0 13.0 4.8 41.3 58.7 (M6) 6 41.27 0.3 ZFC41T 

70 2.75 NW40CF 40.0 13.0 10.2 44.5 58.7 6.8 6 44.45 0.3 ZFC45 

70 2.75 NW40CF 40.0 13.0 10.2 44.5 58.7 (M6) 6 44.45 0.3 ZFC45T 

85 3.38 NW54CF 49.0 16.0 8.0 51.1 72.4 8.4 8 50.80 0.7 ZFC54 (M) 

85 3.38 NW54CF 49.0 16.0 8.0 51.1 72.4 (M8) 8 50.80 0.7 ZFC54T (M) 

114 4.50 NW50CF 49.6 17.5 8.0 51.1 92.1 8.4 8 50.80 1.0 ZFC50 (M)(T) 

114 4.50 NW61CF 61.2 17.5 8.0 63.7 92.1 8.4 8 63.50 0.9 ZFC64 

114 4.50 NW61CF 61.2 17.5 8.0 63.7 92.1 (M8) 8 63.50 0.9 ZFC64T 

114 4.50 NW68CF 68.0 17.5 8.0 70.0 92.1 8.4 8 69.80 0.9 ZFC70 

114 4.50 NW68CF 68.0 17.5 8.0 70.0 92.1 (M8) 8 69.80 0.9 ZFC70T 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 130.2 8.4 16 101.60 1.7 ZFC100 (M) 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 130.2 (M8) 16 101.60 1.7 ZFC100T (M) 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 181.0 8.4 20 152.40 2.6 ZFC150 (M) 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 181.0 (M8) 20 152.40 2.6 ZFC150T (M) 

254 10.00 NW200CF 200.4 24.5 9.5 203.5 231.8 8.4 24 203.20 3.7 ZFC200 (M) 

254 10.00 NW200CF 200.4 24.5 9.5 203.5 231.8 (M8) 24 203.20 3.7 ZFC200T (M) 


305 12.00 NW250CF 250.7 27.0 9.5 254.4 283.0 10.5 32 254.00 6.3 ZFC250 

305 12.00 NW250CF 250.7 27.0 9.5 254.4 283.0 (M10) 32 254.00 6.3 ZFC250T 

305 12.00 NW250CF 250.0 26.0 13.0 256.4 284.0 8.5 32 256.00 6.3 ZFC250M 

305 12.00 NW250CF 250.0 26.0 13.0 256.4 284.0 (M8) 32 256.00 6.3 ZFC250MT 

362 14.25 NW300CF 302.0 30.0 16.0 305.2 334.0 10.5 36 304.80 9.0 ZFC300 

362 14.25 NW300CF 302.0 30.0 16.0 305.2 334.0 (M10) 36 304.80 9.0 ZFC300T 

All dimensions in mm unless otherwise stated. 

Metric 



037

Metric 



304L Rotatable Bored Flanges (FCR Series) 

304L Rotatable Bored Flanges 

Rotatable bored flanges are available in the full 

range of sizes as indicated in the chart below. 

They are normally welded onto chamber tubulations 

or certain specific sizes of component. 

The rotatable nature of the flange allows any 

bolt hole angle variation to be easily accommodated. 

Please note that the smaller sizes of 

flange can accept a number of different standard 

tube sizes. 

Tube Rot Bolt Bolt Tube Size 

Clear Flange Land Counter Tube Hole Hole No. of to Fit Shipping 

OD Pneurop Bore Thickness Thickness Bore Bore PCD Diameter Bolt Flange Weight 

mm inch Equivalent A B C D E F (or thread) Holes Bore kg Order Code 

34 1.33 NW7CF 6.4 7.6 N/A 6.4 19.3 27.0 4.3 6 6.35 0.1 ZFCR97 

34 1.33 NW14CF 13.2 7.6 4.8 14.4 19.3 27.0 4.3 6 14.29 0.1 ZFCR914 (T) 

34 1.33 NW16CF 16.6 7.6 12.7 19.1 19.3 27.0 4.3 6 19.05 0.1 ZFCR919 (1)(M)(T) 

70 2.75 NW14CF 13.2 13.0 4.8 14.4 41.9 58.7 6.8 6 14.29 0.3 ZFCR14 

70 2.75 NW14CF 13.2 13.0 4.8 14.4 41.9 58.7 (M6) 6 14.29 0.3 ZFCR14T 

70 2.75 NW25CF 24.2 13.0 4.8 25.5 41.9 58.7 6.8 6 25.40 0.3 ZFCR25 

70 2.75 NW25CF 24.2 13.0 4.8 25.5 41.9 58.7 (M6) 6 25.40 0.3 ZFCR25T 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 41.9 58.7 6.8 6 38.10 0.3 ZFCR38 (M) 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 41.9 58.7 (M6) 6 38.10 0.3 ZFCR38T (M) 

70 2.75 NW40CF 40.0 13.0 4.8 41.3 41.9 58.7 6.8 6 41.27 0.3 ZFCR41 

70 2.75 NW40CF 40.0 13.0 4.8 41.3 41.9 58.7 (M6) 6 41.27 0.3 ZFCR41T 

85 3.38 NW54CF 49.0 16.0 9.7 51.1 52.6 72.4 8.4 8 50.80 0.7 ZFCR54 

114 4.50 NW50CF 49.6 17.5 8.0 51.1 68.0 92.1 8.4 8 50.80 1.0 ZFCR50 

114 4.50 NW61CF 61.2 17.5 8.0 63.7 68.0 92.1 8.4 8 63.50 0.9 ZFCR64 (M)(T) 

114 4.50 NW61CF 61.2 17.5 8.0 63.7 68.0 92.1 (M8) 8 63.50 0.9 ZFCR64T 

114 4.50 NW68CF 68.0 17.5 8.0 70.0 71.0 92.1 8.4 8 69.80 0.9 ZFCR70 

114 4.50 NW68CF 68.0 17.5 8.0 70.0 71.0 92.1 (M8) 8 69.80 0.9 ZFCR70T 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 104.9 130.2 8.4 16 101.60 1.7 ZFCR100 (M)(T) 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 104.9 130.2 (M8) 16 101.60 1.7 ZFCR100T 

152 6.00 NW100CF 100.0 20.0 9.5 104.5 105.0 130.2 8.4 16 104.00 1.7 ZFCR100M 

152 6.00 NW100CF 100.0 20.0 9.5 104.5 105.0 130.2 (M8) 16 104.00 1.7 ZFCR10MT 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 155.7 181.0 8.4 20 152.40 2.6 ZFCR150 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 155.7 181.0 (M8) 20 152.40 2.6 ZFCR150T 

203 8.00 NW150CF 150.0 22.0 9.5 154.6 155.7 181.0 8.4 20 154.00 2.6 ZFCR150M 

203 8.00 NW150CF 150.0 22.0 9.5 154.6 155.7 181.0 (M8) 20 154.00 2.6 ZFCR15MT 

254 10.00 NW200CF 200.4 24.5 9.5 203.5 206.4 231.8 8.4 24 203.20 3.7 ZFCR200 (M) 


(1) Dimension D refers to external tubulation and not the recess in flange body as per rest of range of flanges. 

(M) Metric version of flanges available on request. Contact Technical Sales Department for details. 

(T) Tapped version of flanges available on request. Contact Technical Sales Department for details. 


Fixed blank flanges are available in the full range 


are normally used to blank off unused chamber 

ports to create a leak-tight assembly. It is also 

possible to machine them as required for the fixing 

of special tube sizes or components that are 

not covered by the standard range of sizes. 



304 Fixed Blank Flanges (FC Series) 

304L Fixed Blank Flanges 

Flange Bolt Hole Bolt Hole Number Shipping 

OD Pneurop Thickness PCD Diameter of Bolt Weight 

mm inch Equivalent B F (or thread) Holes kg Order Code 

34 1.33 NW16CF 7.6 27.0 4.3 6 0.1 ZFC90 

34 1.33 NW16CF 7.6 27.0 (M4) 6 0.1 ZFC90T 

70 2.75 NW35CF 13.0 58.7 6.8 6 0.4 ZFC2 

70 2.75 NW35CF 13.0 58.7 (M6) 6 0.4 ZFC2T 

85 3.38 NW54CF 16.0 72.4 8.4 8 0.7 ZFC3 

85 3.38 NW54CF 16.0 72.4 (M8) 8 0.7 ZFC3T 

114 4.50 NW63CF 17.5 92.1 8.4 8 1.3 ZFC4 

114 4.50 NW63CF 17.5 92.1 (M8) 8 1.3 ZFC4T 

152 6.00 NW100CF 20.0 130.2 8.4 16 3.0 ZFC6 

152 6.00 NW100CF 20.0 130.2 (M8) 16 3.0 ZFC6T 

203 8.00 NW150CF 22.0 181.2 8.4 20 5.5 ZFC8 

203 8.00 NW150CF 22.0 181.2 (M8) 20 5.5 ZFC8T 

254 10.00 NW200CF 24.5 231.8 8.4 24 9.7 ZFC10 

254 10.00 NW200CF 24.5 231.8 (M8) 24 9.7 ZFC10T 


305 12.00 NW250CF 27.0 283.0 10.5 32 16.0 ZFC12 

305 12.00 NW250CF 27.0 283.0 (M10) 32 16.0 ZFC12T 

305 12.00 NW250CF 27.0 284.0 8.5 32 16.0 ZFC12M 

305 12.00 NW250CF 27.0 284.0 (M8) 32 16.0 ZFC12MT 

362 14.25 NW300CF 30.0 334.0 10.5 36 22.0 ZFC1425 

Note: Flanges in size 114-362 mm OD (4.50-14.25 inch) have an additional 0.5 mm recess on the back face. 

Metric 



039

Metric 



304L Rotatable Blank Flanges (FCR Series) 

304L Rotatable Blank Flanges 

All dimensions in mm unless otherwise is stated. 


Rotatable blank flanges are available in the full 



bolt hole angle variations to be easily accommodated. 

These flanges are not normally used 

to blank off unused chamber ports, but are 

machined as required for the mounting of special 

tube sizes or components that are not covered 

by the standard range of sizes. 

Flange Rotatable Bolt Hole Bolt Hole Number Shipping 

OD Pneurop Thickness Tube Bore PCD Diameter of Bolt Weight 

mm inch Equivalent B E F (or thread) Holes kg Order Code 

34 1.33 NW16CF 7.6 19.3 27.0 4.3 6 0.1 ZFCR90 

34 1.33 NW16CF 7.6 19.3 27.0 (M4) 6 0.1 ZFCR90T 

70 2.75 NW35CF 13.0 41.9 58.7 6.8 6 0.4 ZFCR2 

70 2.75 NW35CF 13.0 41.9 58.7 (M6) 6 0.4 ZFCR2T 

114 4.50 NW63CF 17.5 68.0 92.1 8.4 8 1.3 ZFCR4 

114 4.50 NW63CF 17.5 68.0 92.1 (M8) 8 1.3 ZFCR4T 

152 6.00 NW100CF 20.0 104.9 130.2 8.4 16 3.0 ZFCR6 (T) 

203 8.00 NW150CF 22.0 155.7 181.2 8.4 20 5.5 ZFCR8 (T) 

254 10.00 NW200CF 24.5 206.4 231.8 8.4 24 9.7 ZFCR10 (T) 



of sizes as indicated in the chart below. They are 

normally welded onto chamber tubulations or 

certain specific sizes of component. Please note 

that for the smaller sizes of flange there are a 

number of different standard tube sizes that 

they can accept. 

(1) Non spigotted flange 

(2) Non spigotted flange and tapped holes 

(3) Dimension D refers to external tubulation and not the recess in 

flange body as per rest of range of flanges 

(M) Metric version available on request. 

Contact Technical Sales Department for details. 

(T) Tapped version available on request. 

Contact Technical Sales Department for details. 


316LN Fixed Bored Flanges (FCL Series) 

316LN Fixed Bored Flanges 

Tube Bolt Bolt Tube Size 

Clear Flange Land Counter Hole Hole No. of to Fit Shipping 

OD Pneurop Bore Thickness Thickness Bore PCD Diameter Bolt Flange Weight 

mm inch Equivalent A B C D F (or thread) Holes Bore kg Order Code 

34 1.33 NW7CF 6.4 7.6 N/A 6.4 27.0 4.3 6 6.35 0.1 ZFCL97 (T) 

34 1.33 NW12CF 6.4 7.6 N/A 12.7 27.0 4.3 6 12.7 0.1 ZFCL912 (T) 

34 1.33 NW14CF 13.2 7.6 4.8 14.4 27.0 4.3 6 14.29 0.1 ZFCL914 (T) 

34 1.33 NW16CF 16.6 7.6 12.7 19.1 27.0 4.3 6 19.05 0.1 ZFCL919 (3) 

34 1.33 NW16CF 16.6 7.6 4.8 19.1 27.0 4.3 6 19.05 0.1 ZFCL19NS (1) 

34 1.33 NW16CF 16.6 7.6 4.8 19.1 27.0 (M4) 6 19.05 0.1 ZFCL19NT (2) 

70 2.75 NW14CF 13.2 13.0 4.8 14.4 58.7 6.8 6 14.29 0.3 ZFCL14 

70 2.75 NW25CF 24.2 13.0 4.8 25.5 58.7 6.8 6 25.40 0.3 ZFCL25 (T) 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 58.7 6.8 6 38.10 0.3 ZFCL38 (M) 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 58.7 (M6) 6 38.10 0.3 ZFCL38T (M) 

70 2.75 NW40CF 40.0 13.0 4.8 41.3 58.7 6.8 6 41.27 0.3 ZFCL41 

70 2.75 NW40CF 40.0 13.0 4.8 41.3 58.7 (M6) 6 41.27 0.3 ZFCL41T 

70 2.75 NW40CF 40.0 13.0 10.2 44.5 58.7 6.8 6 44.45 0.3 ZFCL45 

70 2.75 NW40CF 40.0 13.0 10.2 44.5 58.7 (M6) 6 44.45 0.3 FCL45T 

114 4.50 NW50CF 49.6 17.5 8.0 51.1 92.1 8.4 8 50.80 1.0 ZFCL50 

114 4.50 NW63CF 61.2 17.5 8.0 63.7 92.1 8.4 8 63.50 0.9 ZFCL64 

114 4.50 NW63CF 61.2 17.5 8.0 63.7 92.1 (M8) 8 63.50 0.9 ZFCL64T 

114 4.50 NW63CF 68.0 17.5 8.0 70.0 92.1 8.4 8 69.80 0.9 ZFCL70 

114 4.50 NW63CF 68.0 17.5 8.0 70.0 92.1 (M8) 8 69.80 0.9 ZFCL70T 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 130.2 8.4 16 101.60 1.7 ZFCL100 (M) 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 130.2 (M8) 16 101.60 1.7 ZFCL100T (M) 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 181.0 8.4 20 152.40 2.6 ZFCL150 (M) 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 181.0 (M8) 20 152.40 2.6 ZFCL150T (M) 

254 10.00 NW200CF 200.4 24.5 9.5 203.5 231.8 8.4 24 203.20 3. 7 ZFCL200 (M) 

254 10.00 NW200CF 200.4 24.5 9.5 203.5 231.8 (M8) 24 203.20 3.7 ZFCL200T (M) 


305 12.00 NW250CF 250.7 27.0 9.5 254.4 283.0 10.5 32 254.00 6.3 ZFCL250 

305 12.00 NW250CF 250.7 27.0 9.5 254.4 283.0 (M10) 32 254.00 6.3 ZFCL250T 

305 12.00 NW250CF 250.0 26.0 13.0 256.4 284.0 8.5 32 256.00 6.3 ZFCL250M 

305 12.00 NW250CF 250.0 26.0 13.0 256.4 284.0 (M8) 32 256.00 6.3 ZFCL25MT 

362 14.25 NW300CF 302.0 30.0 16.0 305.2 334.0 10.5 36 304.80 9.0 ZFCL300 

362 14.25 NW300CF 302.0 30.0 16.0 305.2 334.0 (M10) 36 304.80 9.0 ZFCL300T 


Metric 



041

Metric 



316LN Rotatable Bored Flanges (FCRL Series) 

316LN Rotatable Bored Flanges 


(M) Metric version of flanges available on request. Contact Technical Sales Department for details. 





or to certain specific sizes of component. 





tube sizes. 

Tube Rotatable Bolt Bolt Tube Size 

Clear Flange Land Counter Tube Hole Hole No. of to Fit Shipping 

OD Pneurop Bore Thickness Thickness Bore Bore PCD Diameter Bolt Flange Weight 

mm inch Equivalent A B C D E F (or thread)Holes Bore kg Order Code 

34 1.33 NW7CF 6.4 7.6 N/A 6.4 19.3 27.0 4.3 6 6.35 0.1 ZFCRL97 

34 1.33 NW14CF 13.2 7.6 4.8 14.4 19.3 27.0 4.3 6 14.29 0.1 ZFCRL914(T) 

34 1.33 NW16CF 16.6 7.6 12.7 19.1 19.3 27.0 4.3 6 19.05 0.1 ZFCRL919 (M)(T) 

70 2.75 NW14CF 13.2 13.0 4.8 14.4 41.9 58.7 6.8 6 14.29 0.3 ZFCRL14 

70 2.75 NW14CF 13.2 13.0 4.8 14.4 41.9 58.7 (M6) 6 14.29 0.3 ZFCRL14T 

70 2.75 NW25CF 24.2 13.0 4.8 25.5 41.9 58.7 6.8 6 25.40 0.3 ZFCRL25 

70 2.75 NW25CF 24.2 13.0 4.8 25.5 41.9 58.7 (M6) 6 25.40 0.3 ZFCRL25T 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 41.9 58.7 6.8 6 38.10 0.3 ZFCRL38 (M) 

70 2.75 NW35CF 36.9 13.0 4.8 38.3 41.9 58.7 (M6) 6 38.10 0.3 ZFCRL38T (M) 

70 2.75 NW38CF 40.0 13.0 4.8 41.3 41.9 58.7 6.8 6 41.27 0.3 ZFCRL41 

70 2.75 NW38CF 40.0 13.0 4.8 41.3 41.9 58.7 (M6) 6 41.27 0.3 ZFCRL41T 

114 4.50 NW50CF 49.6 17.5 8.0 51.1 68.0 92.1 8.4 8 50.80 1.0 ZFCRL50 

114 4.50 NW63CF 61.2 17.5 8.0 63.7 68.0 92.1 8.4 8 63.50 0.9 ZFCRL64 

114 4.50 NW61CF 61.2 17.5 8.0 63.7 68.0 92.1 (M8) 8 63.50 0.9 ZFCRL64T 

114 4.50 NW68CF 68.0 17.5 8.0 70.0 71.0 92.1 8.4 8 69.80 0.9 ZFCRL70 

114 4.50 NW68CF 68.0 17.5 8.0 70.0 71.0 92.1 (M8) 8 69.80 0.9 ZFCRL70T 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 104.9 130.2 8.4 16 101.60 1.7 ZFCRL100 

152 6.00 NW100CF 99.4 20.0 9.5 101.9 104.0 130.2 (M8) 16 101.60 1.7 ZFCRL10T 

152 6.00 NW100CF 100.0 20.0 9.5 104.5 105.0 130.2 8.4 16 104.00 1.7 ZFCRL10M (T) 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 155.7 181.0 8.4 20 152.40 2.6 ZFCRL150 (M)(T) 

203 8.00 NW150CF 149.7 22.0 9.5 152.6 155.7 181.0 (M8) 20 152.40 2.6 ZFCRL15T 

203 8.00 NW150CF 150.0 22.0 9.5 152.6 155.7 181.0 8.4 20 154.00 2.6 ZFCRL15M (T) 

254 10.00 NW200CF 200.4 24.5 9.5 203.5 206.4 231.8 8.4 24 203.20 3.7 ZFCRL200 (M)(T) 











316LN Fixed Blank Flanges (FCL Series) 

316LN Fixed Blank Flanges 

Flange Bolt Hole Bolt Hole Number Shipping 

OD Pneurop Thickness PCD Diameter of Bolt Weight 

mm inch Equivalent B F (or thread) Holes kg Order Code 

34 1.33 NW16CF 7.6 27.0 4.3 6 0.1 ZFCL90 

34 1.33 NW16CF 7.6 27.0 (M4) 6 0.1 ZFCL90T 

70 2.75 NW35CF 13.0 58.7 6.8 6 0.4 ZFCL2 

70 2.75 NW35CF 13.0 58.7 (M6) 6 0.4 ZFCL2T 

114 4.50 NW63CF 17.5 92.1 8.4 8 1.3 ZFCL4 

114 4.50 NW63CF 17.5 92.1 (M8) 8 1.3 ZFCL4T 

152 6.00 NW100CF 20.0 130.2 8.4 16 3.0 ZFCL6 

152 6.00 NW100CF 20.0 130.2 (M8) 16 3.0 ZFCL6T 

203 8.00 NW150CF 22.0 181.2 8.4 20 5.5 ZFCL8 

203 8.00 NW150CF 22.0 181.2 (M8) 20 5.5 ZFCL8T 

254 10.00 NW200CF 24.5 231.8 8.4 24 9.7 ZFCL10 

254 10.00 NW200CF 24.5 231.8 (M8) 24 9.7 ZFCL10T 

Please note - No accepted international standard dimensions exist for flanges with an OD of 300 mm or greater 

305 12.00 NW250CF 27.0 283.0 10.3 32 16.0 ZFCL12 

305 12.00 NW250CF 27.0 283.0 (M10) 32 16.0 ZFCL12T 

305 12.00 NW250CF 26.0 284.0 8.5 32 16.0 ZFCL12M 

305 12.00 NW250CF 26.0 284.0 (M8) 32 16 ZFCL12MT 

362 14.25 NW300CF 30.0 334.0 10.5 36 22.0 ZFCL1425 

Note: Flanges in sizes 114-362 mm OD (4.50-14.25 inch) have an additional 0.5 mm recess on the back face. 

Metric 



043

Metric 



316LN Rotatable Blank Flanges (FCRL Series) 

316LN Rotatable Blank Flanges 

Flange Rotatable Bolt Hole Bolt Hole Number Shipping 

OD Pneurop Thickness Tube bore PCD Diameter of Bolt Weight 

mm inch Equivalent B E F (or thread) Holes kg Order Code 

34 1.33 NW16CF 7.6 19.3 27.0 4.3 6 0.1 ZFCRL90 

34 1.33 NW16CF 7.6 19.3 27.0 (M4) 6 0.1 ZFCRL90T 

70 2.75 NW35CF 13.0 41.9 58.7 6.8 6 0.4 ZFCRL2 

70 2.75 NW35CF 13.0 41.9 58.7 (M6) 6 0.4 ZFCRL2T 

114 4.50 NW63CF 17.5 68.0 92.1 8.4 8 1.3 ZFCRL4 

114 4.50 NW63CF 17.5 68.0 92.1 (M8) 8 1.3 ZFCRL4T 

150 6.00 NW100CF 20.0 104.9 130.2 8.4 16 3.0 ZFCRL6 (T) 

200 8.00 NW150CF 22.0 155.7 181.2 8.4 20 5.5 ZFCRL8 (T) 

250 10.00 NW200CF 24.5 206.4 231.8 8.4 24 9.7 ZFCRL10 













Double-sided Flanges 304L (FC Series) and 316LN 

(FCL Series) 

Double-sided flanges are used for several different 

purposes including the spacing out of components 

from a flange. It is also possible to drill 

a hole from the outside diameter of the flange to 

the inside. If a thin tube and flange assembly are 

then welded in place, it allows you to introduce 

gases or have extra pumping around a component 

that either does not have any free ports or 

is limited on space. There is a version of the 70 

mm flange that has two KF ports added into 

its OD to permit this. Special versions of these 

flanges can be supplied on request. For doublesided 

blank flanges please see page 062. 


Double-sided Flanges in 304L and 316LN 

Clear Flanges Thickness Shipping 

OD Bore B B Weight 

mm inch A Material mm inch kg Order Code 

FC Series 304L 

34 1.33 14.4 304L 10.0 0.39 0.1 ZFC914D 

34 1.33 Blank 304L 10.0 0.39 0.1 ZFC90D 

70 2.75 38.0 304L 16.0 0.63 0.3 ZFC38D 

70 2.75 38.0 304L 16.0 0.63 0.3 ZFC38DKF (1) 

70 2.75 Blank 304L 16.0 0.63 0.4 ZFC2D 

114 4.50 64.4 304L 17.5 0.69 0.9 ZFC64D 

114 4.50 Blank 304L 17.5 0.69 1.3 ZFC4D 

152 6.00 102.4 304L 20.0 0.79 1.7 ZFC100D 

152 6.00 Blank 304L 20.0 0.79 3.0 ZFC6D 

203 8.00 153.3 304L 22.0 0.87 2.6 ZFC150D 

203 8.00 Blank 304L 22.0 0.87 5.5 ZFC8D 

FCL Series 316LN 

34 1.33 14.4 316LN 10.0 0.39 0.1 ZFCL914D 

34 1.33 Blank 316LN 10.0 0.39 0.1 ZFCL90D 

70 2.75 38.0 316LN 16.0 0.63 0.3 ZFCL38D 

70 2.75 Blank 316LN 16.0 0.63 0.4 ZFCL2D 

114 4.50 64.4 316LN 17.5 0.69 0.9 ZFCL64D 

114 4.50 Blank 316LN 17.5 0.69 1.3 ZFCL4D 

152 6.00 102.4 316LN 20.0 0.79 1.7 ZFCL100D 

152 6.00 Blank 316LN 20.0 0.79 3.0 ZFCL6D 

203 8.00 153.3 316LN 22.0 0.87 2.6 ZFCL150D 

203 8.00 Blank 316LN 22.0 0.87 5.5 ZFCL8D 


(1) ZFC38DKF has two radial KF ports as described above. 

Metric 



045

Metric 



Zero Length Adaptor Flanges 304L and 316LN 

Zero Length Adaptor Flanges, 304L and 316LN 

This type of flange is used to adapt from one 

flange size to another. The zero length indicates 

that it is no thicker than a standard flange 

(except the 34 mm to 70 mm OD adaptor). The 

larger flange OD has through bolt holes enabling 

ordinary nut and bolt kits to be used. The 

smaller flange OD has tapped holes so the bolts 

that are used must be shorter than normal. We 

offer bolt kits for both sizes of flange. 

Flange 1 Flange 2 

Major Bolt Minor Clear Thickness Shipping 

OD Holes OD Bolt Bore B B Weight 

mm inch mm to mm inch Holes A Material mm inch kg Order Code 

AZ Series 304L 

70 2.75 Clear 6.8 to 34 1.33 Tapped M4 16.0 304L 20.0 0.79 0.4 ZAZ3470 












AZL Series 316LN 

70 2.75 Clear 6.8 to 34 1.33 Tapped M4 16.0 316LN 20.0 0.79 0.4 ZAZL3470 














Klein Flange to Conflat Flange Adaptors (KA Series) 

It is often necessary to join a Conflat flange to 

a Klein flange. This can be achieved easily by 

using an adaptor. Please note that some of the 

Conflat flanges have tapped holes instead of 

through holes, which means that the connecting 

bolts cannot be inserted from the KF side of the 

flange when making the connection. The table 

also includes the order codes for the copper 

gasket, Viton ® o-ring and carrier, together with 

the flange clamp that is required to complete 

the seal. 

(1) Please Note - Where bolt holes are tapped, bolts cannot be inserted from KF side of flange. 


Klein to Conflat Flanges Adaptors 

Conflat Length of Shipping 

OD Use Use Fitting L Weight 

mm inch Holes (1) Gasket to Klein O-ring Clamp mm inch kg Order Code 

34 1.33 Tapped M4 ZCU19 to NW10KF KK10VCS KKF16CA 21 0.83 0.2 ZKA3410T 


70 2.75 Clear hole ZCU38 to NW10KF KK10VCS KKF16CA 31 1.22 0.5 ZKA7010 








Metric 



047

Metric 

Flange 

Accessories 

Accessories 

Nut Plates 

Flange 

OD Nut No. of No. of 

mm inch Plates Bolts Washers Order Code 

34 1.33 2 6 6 ZNPS133 

70 2.75 2 6 6 ZNPS2 

114 4.50 2 8 8 ZNPS4 

Nut, Bolt and Washer Sets 

For reliable UHV seals, specially selected stainless 

steel bolt sets are recommended; see table 

on page 050. The materials are selected to match 

the expansion and contraction of the Conflat 

flanges during bakeout. This minimises the risk 

of vacuum leaks by differential expansion. 

We always recommend that bolts are lightly 

coated with an anti-seize thread lubricant during 

construction. This prevents seizure after a 

system bakeout. Be careful not to introduce any 

of this compound into the vacuum system as it 

will cause contamination. 

Anti-seize thread lubricant order code is ZTL 

(28 g tube). 

Alternatively we can supply silver-plated bolt 

sets. 

Nut Plate Sets 

Where access behind a flange is limited, or 

tapped flanges are required but not preferred, it 

is possible to use a nut plate set instead. Each set 

consists of two half-moon shaped metal pieces 

with tapped holes and set of bolt and washers. 

Access with a spanner is only required from the 

top as the plates are self locating behind the 

flange. If the threads become damaged, it is 

easy enough to replace the plate without having 

to touch the flange to which it is mounted. 

Nut plate sets are available for 34 mm (1.33"), 

70 mm (2.75"), and 114 mm (4.5") OD Conflat 

flanges. We always recommend that bolts are 

lightly coated with an anti-seize thread lubricant 

during construction. This prevents seizure after 

a system bakeout. Be careful not to introduce 

any of this compound into the vacuum system 

as it will cause contamination. 


Thread Lubricant 

This may be used on external nuts and bolts; it 

is used to stop the nuts seizing to the bolts when 

the system is baked. It should be applied sparingly 

to the thread of the bolts during assembly. 

A small brush is an ideal way of applying the 

lubricant. 

Important - This lubricant is not UHV compatible 

so use it carefully, ensuring that no lubricant 

enters into the vacuum system. 

Order Code 

ZTL (28 g (1 oz) tube). 

Nylon Gloves 

To stop greasy fingers contaminating parts 

that are going inside the UHV system, we supply 

packs of clean nylon gloves. These should 

always be used when handling items. They 

should be regularly changed. 

Order Code 

ZNG10 (pack of 5 pairs) 


General Accessories 

Metric 

Flange 

Accessories 

049

Metric 

Flange 

Accessories 

Conflat Flange Accessories 


OD Comm- High 

Copper Gaskets 

Silver Alumin- Bolt 

mm Flange Type ercial Quality Annealed Plated Blank Viton ® ium Set(*) 

34 Standard Fixed or Rotatable ZCUC19 ZCU19 ZCUA19 ZCUSP19 ZCUB19 ZVIT19 ZAL19 ZM4B20 (1) 

34 Double Sided ZCUC19 ZCU19 ZCUA19 ZCUSP19 ZCUB19 ZVIT19 ZAL19 ZM4B35 (1) 

34 Tapped M4 ZCUC19 ZCU19 ZCUA19 ZCUSP19 ZCUB19 ZVIT19 ZAL19 ZM4B16 (1) 

70 Standard Fixed or Rotatable ZCUC38 ZCU38 ZCUA38 ZCUSP38 ZCUB38 ZVIT38 ZAL38 ZM6B35 (2) 

70 Double Sided ZCUC38 ZCU38 ZCUA38 ZCUSP38 ZCUB38 ZVIT38 ZAL38 ZM6B50 (2) 

70 Tapped M6 ZCUC38 ZCU38 ZCUA38 ZCUSP38 ZCUB38 ZVIT38 ZAL38 ZM6S25 (2) 

85 Standard Fixed or Rotatable ZCUC54 ZCU54 ZM8B50 

85 Tapped M8 ZCUC54 ZCU54 ZM8B50 

114 Standard Fixed or Rotatable ZCUC64 ZCU64 ZCUA64 ZCUSP64 ZVIT64 ZAL64 ZM8B45 (3) 

114 Double Sided ZCUC64 ZCU64 ZCUA64 ZCUSP64 ZVIT64 ZAL64 ZM8B60 (3) 

114 Tapped M8 ZCUC64 ZCU64 ZCUA64 ZCUSP64 ZVIT64 ZAL64 ZM8S35 (3) 

152 Standard Fixed or Rotatable ZCUC100 ZCU100 ZCUA100 ZCUSP100 ZVIT100 ZAL100 ZM8B50 

152 Double Sided ZCUC100 ZCU100 ZCUA100 ZCUSP100 ZVIT100 ZAL100 ZM8B70 

152 Tapped M8 ZCUC100 ZCU100 ZCUA100 ZCUSP100 ZVIT100 ZAL100 ZM8S40 







305 Standard Fixed ZCUC250 ZCU250 ZCUSP250 ZAL250 ZM10B65 

305 Double Sided ZCUC250 ZCU250 ZCUSP250 ZAL250 ZM10B90 

305 Tapped M10 ZCUC250 ZCU250 ZCUSP250 ZAL250 ZM10S50 

362 Standard Fixed ZCUC300 ZCU300 ZM10B75 

(*) Most bolt kits come in packs of 25 except the ZM10B65, ZM10B90, ZM10S50 which are in 35’s and ZM10B75 which is a pack of 

40. Bolts for tapped flanges with UNC threads are available upon request. Contact the Sales Office for details. 

(1) Nut plate set for this flange = ZNPS133 (2) Nut plate set for this flange = ZNPS2 (3) Nut plate set for this flange = ZNPS4 

For more information on the full range of Conflat gaskets see pages 069 to 076. 

Zero Length Flange Accessories 

Zero Length Adaptor Accessories 

Zero Length Adaptor Order Code Flange 1 Gaskets Flange 2 Gaskets 

304L 316LN Copper Viton ® Bolt Set Copper Viton ® Bolt Set 

ZAZ3470 or ZAZL3470 ZCU38 ZVIT38 ZM6B35 ZCUA19 ZVIT19 ZM4S16 













Introduction to Conflat Flanges 

• Wide range of Imperial and Metric standard 

sizes 

• All flanges manufactured on computer 

controlled CNC machines for accuracy 

• Available in 304L or 316LN stainless steel 

• Low outgassing rates, 450 °C) without 

leaking. 

VG Scienta’s range of UHV flanges is world 

renowned both for its quality and range of sizes 

and materials. The complete range of flanges are 

fully compatible with the internationally agreed 

ISO/Pneurop standards and will connect to any 

other flange that also complies with this standard 

(for flanges with a diameter greater than 

300 mm no such standards exist at present). All 

flange OD dimensions are nominal. 

Method of Sealing 

The UHV seal is made by trapping a copper gasket 

between two sexless flanges that have a sharp 

knife-edge profiled onto their operating face. 

When joined together with a set of connecting 

bolts, the knife-edges cut into the surface of the 

copper gasket to make a seal that is UHV leak 

tight. When exposed to bakeout temperatures 

the shape of the knife-edge ensures that the seal 

remains leak tight by resisting any differential 

movements between the copper gasket and the 

stainless steel flange parts. 


For full information on: 

i) NW versus FC Designations 

ii) Tube Sizes - Imperial versus Metric Tube 

iii) Tube Counterbore Depth 

please refer to page 034. 


Imperial Flange Range 

Fixed and Rotatable Flanges 

To aid the construction of UHV chambers and 

components, VG Scienta flanges are available in 

both fixed and rotatable configurations. Fixed 

flanges are a single machined item with the 

bolt hole orientation fixed into position once 

they are welded onto a chamber or component. 

Rotatable flanges are manufactured in two parts 

with the knife-edge part and external bolt hole 

ring being separate. Once the knife-edge part is 

welded in position it is easy to change the orientation 

of the bolt holes relative to the axis of the 

port. This makes rotatable flanges ideal for the 

situations where alignment of a component to 

a chamber (or another component) needs to be 

set accurately before the flange mounting bolts 

are tightened. 

Please Note: It is not advisable to have two 

rotatable flanges at the same joint. 

Internal Weld 

Copper Gasket 

Flanges are bolted together with a copper 

gasket between the knife edges. 

Imperial 



051

Imperial 



Imperial Conflat Flange Type Quick Reference 

Comparison Chart IMPORTANT PRODUCT INFORMATION 

See page 034 concerning FC and NW designations 

Imperial Flange Comparison Chart 

304L 304L 304L 304L 316LN 316LN 316LN 316LN 

OD Pneurop Fixed Rotatable Fixed Rotatable Fixed Rotatable Fixed Rotatable 

mm inch Equivalent Bored Bored Blank Blank Bored Bored Blank Blank 

34 1.33 Blank ZF90A ZFR90A ZFL90A ZFRL90A 

34 1.33 Blank ZF90TA ZFL90TA 

34 1.33 NW7CF ZF97A ZFR97A ZFL97A ZFRL97A 

34 1.33 NW12CF ZF912A ZFL912A 



34 1.33 NW16CF ZF19NSA ZFL19NSA 

34 1.33 NW16CF ZF19NSTA ZFL19NTA 

70 2.75 Blank ZF2A ZFR2A ZFL2 ZFRL2A 

70 2.75 Blank Tapped ZF2TA ZFR2TA ZFL2TA ZFRL2TA 


70 2.75 NW14CF ZFR14TA ZFRL14TA 


70 2.75 NW25CF ZFR25TA ZFRL25TA 


70 2.75 NW35CF ZF38TA ZFR38TA ZFL38TA ZFRL38TA 



70 2.75 NW45CF ZF45A ZFL45A 

70 2.75 NW45CF ZF45TA ZFL45TA 

85 3.38 Blank ZF3A ZFL3A 

85 3.38 Blank Tapped ZF3TA ZFL3TA 











152 6.00 NW100CF ZF100TA ZFR100TA ZFL100TA 





254 10.00 Blank ZFL10A ZFRL10A 

254 10.00 Blank Tapped ZF10TA ZFL10TA 



Please Note - No accepted international standard dimensions exist for flanges with an OD of 300mm or greater. 

300 12.00 Blank ZF12A ZFL12A 

300 12.00 NW250CF ZF250A ZFL250A 

336 13.25 Blank ZF1325A 

336 13.25 Blank Tapped ZF1325TA 

336 13.25 ZF1310A 

336 13.25 ZF1310TA 

336 13.25 ZF1375A 

336 13.25 ZF1375TA 

355 14.00 ZF1400A 

355 14.00 ZF1412A 

362 14.25 Blank ZF1425A ZFL1425A 

362 14.25 NW300CF ZF300A ZFL300A 

indicates clearance bolt holes indicates tapped bolt holes 




are normally welded on to chamber tubulations 

or certain specific sizes of component. Please 

note that the smaller sizes of flange can accept a 

number of different standard tube sizes. 

Tapped version available for all sizes. 

Example ZF2150A (plain bolt holes) becomes 

ZF2150TA (tapped bolt holes). 

Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 


304L Fixed Bored Flanges (F Series) 

304L Fixed Bored Flanges 

Tube Bolt 

Clear Flange Land Counter Hole Bolt No. of Shipping 

OD Bore Thickness Thickness Bore PCD Hole Bolt Weight 

inch mm A B C D F Diameter Holes lb Order Code 

1.33 34 0.26 0.29 N/A 0.26 1.06 0.17 6 0.25 ZF97A 

1.33 34 0.50 0.29 N/A 0.50 1.06 0.17 6 0.25 ZF912A 

1.33 34 0.52 0.29 0.17 0.56 1.06 0.17 6 0.25 ZF914A 

1.33 34 0.65 0.50 0.50 N/A 1.06 0.17 6 0.25 ZF919A 

1.33 34 0.65 0.29 0.17 0.75 1.06 0.17 6 0.25 ZF19NSA 

2.125 54 0.51 0.47 N/A N/A 1.63 0.27 4 0.50 ZF2150A 

2.125 54 0.70 0.47 0.17 0.76 1.63 0.27 4 0.50 ZF2175A 

2.125 54 0.95 0.47 0.17 1.00 1.63 0.27 4 0.50 ZF2110A 

2.75 70 0.52 0.50 0.21 0.57 2.31 0.27 6 0.75 ZF14A 

2.75 70 0.96 0.50 0.21 1.01 2.31 0.27 6 0.75 ZF25A 

2.75 70 1.46 0.50 0.21 1.50 2.31 0.27 6 0.75 ZF38A 

2.75 70 1.58 0.50 0.21 1.63 2.31 0.27 6 0.75 ZF41A 

2.75 70 1.58 0.50 0.39 1.75 2.31 0.27 6 0.75 ZF45A 

3.375 86 1.44 0.63 0.22 1.51 2.85 0.34 8 1.00 ZF3315A 

3.375 86 1.94 0.63 0.22 2.00 2.85 0.34 8 1.00 ZF3320A 

4.5 114 2.00 0.69 0.37 1.96 3.63 0.34 8 2.00 ZF50A 

4.5 114 2.41 0.69 0.37 2.50 3.63 0.34 8 2.00 ZF64A 

4.5 114 2.68 0.69 0.37 2.76 3.63 0.34 8 2.00 ZF70A 

4.625 117.5 2.44 0.75 0.37 2.51 4.03 0.34 10 2.50 ZF4625A 

4.625 117.5 2.94 0.75 0.37 3.00 4.03 0.34 10 2.50 ZF463A 

6 151.5 3.91 0.78 0.44 4.00 5.13 0.34 16 3.50 ZF100A 

6.75 171.5 3.87 0.84 0.46 4.00 5.97 0.34 18 5.00 ZF6740A 

6.75 171.5 4.93 0.84 0.46 5.00 5.97 0.34 18 5.00 ZF6750A 

8 202.5 5.89 0.88 0.50 6.00 7.12 0.34 20 5.50 ZF150A 

10 254 7.89 0.97 0.50 8.01 9.13 0.34 24 7.50 ZF200A 

12 305 9.87 1.02 0.50 10.02 11.18 0.34 32 10.00 ZF250A 

13.25 337 9.86 1.12 0.50 10.02 12.06 0.39 30 18.00 ZF1310A 

13.25 337 10.63 1.12 0.50 12.02 12.06 0.39 30 14.00 ZF1375A 

14 356 11.75 1.12 0.50 12.02 12.81 0.39 30 13.00 ZF1412A 

14.25 362 11.89 1.18 0.63 12.01 13.15 0.41 36 19.80 ZF300A 

All dimensions in inches unless otherwise stated. 

Imperial 



053

Imperial 



304L Rotatable Bored Flanges (FR Series) 

304L Rotatable Bored Flanges 




or certain specific sizes of component. 





tube sizes. 




Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 

Tube Rot' Tube Bolt 

Clear Flange Land Counter Counter Hole Bolt No. of Shipping 

OD Bore Thickness Thickness Bore Bore PCD Hole Bolt Weight 

inch mm A B C D E F Diameter Holes lb Order Code 

1.33 34 0.26 0.29 N/A 0.26 0.76 1.06 0.17 6 0.25 ZFR97A 

1.33 34 0.52 0.29 0.17 0.56 0.76 1.06 0.17 6 0.25 ZFR914A 

1.33 34 0.65 0.50 0.50 N/A 0.76 1.06 0.17 6 0.25 ZFR919A 

2.125 54 0.51 0.47 N/A N/A 1.10 1.63 0.27 4 0.50 ZFR2150A 

2.125 54 0.70 0.47 0.17 0.76 1.10 1.63 0.27 4 0.50 ZFR2175A 

2.125 54 0.95 0.47 0.17 1.00 1.10 1.63 0.27 4 0.50 ZFR2110A 

2.75 70 0.52 0.50 0.21 0.57 1.69 2.31 0.27 6 0.75 ZFR14A 

2.75 70 0.96 0.50 0.21 1.01 1.69 2.31 0.27 6 0.75 ZFR25A 

2.75 70 1.46 0.50 0.21 1.50 1.69 2.31 0.27 6 0.75 ZFR38A 

2.75 70 1.58 0.50 0.21 1.63 1.69 2.31 0.27 6 0.75 ZFR41A 

3.375 86 1.44 0.63 0.22 1.51 2.07 2.85 0.34 8 1.00 ZFR3315A 

3.375 86 1.94 0.63 0.22 2.00 2.07 2.85 0.34 8 1.00 ZFR3320A 

4.5 114 2.00 0.69 0.37 1.96 2.80 3.63 0.34 8 2.00 ZFR50A 

4.5 114 2.41 0.69 0.37 2.50 2.80 3.63 0.34 8 2.00 ZFR64A 

4.5 114 2.68 0.69 0.37 2.76 2.80 3.63 0.34 8 2.00 ZFR70A 

4.625 117.5 2.44 0.75 0.37 2.51 3.10 4.03 0.34 10 2.50 ZFR4625A 

4.625 117.5 2.94 0.75 0.37 3.00 3.10 4.03 0.34 10 2.50 ZFR463A 

6 151.5 3.91 0.78 0.44 4.00 4.13 5.13 0.34 16 3.50 ZFR100A 

6.75 171.5 3.87 0.84 0.46 4.00 5.10 5.97 0.34 18 4.50 ZFR6740A 

6.75 171.5 4.93 0.84 0.46 5.00 5.10 5.97 0.34 18 4.50 ZFR675A 

8 202.5 5.89 0.88 0.50 6.00 6.13 7.13 0.34 20 5.50 ZFR150A 

10 254 7.89 0.97 0.50 8.01 8.15 9.13 0.34 24 7.50 ZFR200A 













Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 


304L Fixed Blank Flanges (F Series) 

304L Fixed Blank Flange 

Flange Bolt Hole No. of Shipping 

OD Thickness PCD Bolt Hole Bolt Weight 

inch mm B F Diameter Holes lb Order Code 

1.33 34 0.29 1.06 0.17 6 0.2 ZF90A 

2.125 54 0.47 1.63 0.27 4 0.5 ZF21A 

2.75 70 0.50 2.31 0.27 6 0.9 ZF2A 

3.375 86 0.63 2.85 0.34 8 1.5 ZF3A 

4.5 114 0.68 3.63 0.34 8 2.9 ZF4A 

4.625 117.5 0.75 4.03 0.34 10 5.5 ZF46A 

6 151.5 0.78 5.13 0.34 16 6.6 ZF6A 

6.75 171.5 0.84 5.97 0.34 18 10.0 ZF675A 

8 202.5 0.88 7.13 0.34 20 12.0 ZF8A 

10 254 0.97 9.13 0.34 24 21.0 ZF10A 

12 305 1.02 11.18 0.34 32 35.0 ZF12A 

13.25 337 1.12 12.06 0.39 30 40.0 ZF1325A 

14 356 1.12 12.81 0.39 30 44.0 ZF1400A 

14.25 362 1.18 13.15 0.41 36 48.0 ZF1425A 


NB: Sizes 4.5 - 14.25 inch have an additional 0.5 inch recess on the back face 

Imperial 



055

Imperial 



304L Rotatable Blank Flanges (FR Series) 

304L Rotatable Blank Flanges 











Example ZFR46A (plain bolt holes) becomes 

ZFR46TA (tapped bolt holes). 

Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 

Rotat' Tube Bolt 

Flange Counter Hole No. of Shipping 

OD Thickness Bore PCD Bolt Hole Bolt Weight 

inch mm B E F Diameter Holes lb Order Code 

1.33 34 0.29 0.76 1.06 0.17 6 0.2 ZFR90A 

2.125 54 0.47 1.10 1.63 0.27 4 0.5 ZFR21A 

2.75 70 0.5 1.69 2.31 0.27 6 0.9 ZFR2A 

3.375 86 0.63 2.07 2.85 0.34 8 1.5 ZFR3A 

4.5 114 0.69 2.80 3.63 0.34 8 2.9 ZFR4A 

4.625 117.5 0.75 3.10 4.03 0.34 10 5.5 ZFR46A 

6 151.5 0.78 4.13 5.13 0.34 16 6.6 ZFR6A 

6.75 171.5 0.84 5.10 5.97 0.34 18 10.0 ZFR67A 

8 202.5 0.88 6.13 7.13 0.34 20 12.0 ZFR8A 

10 254 0.97 8.15 9.13 0.34 24 21.0 ZFR10A 

All dimensions in inches unless otherwise is stated. 



of sizes as indicated in the chart below. They are 

normally welded onto chamber tubulations or 

certain specific sizes of component. Please note 

that for the smaller sizes of flange there are a 

number of different standard tube sizes that 

they can accept. 




Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 


316LN Fixed Bored Flanges (FL Series) 

316LN Fixed Bored Flanges 


Tube Bolt 

Clear Flange Land Counter Hole Bolt No. of Shipping 

OD Bore Thickness Thickness Bore PCD Hole Bolt Weight 

inch mm A B C D F Diameter Holes lb Order Code 

1.33 34 0.26 0.29 N/A 0.26 1.06 0.17 6 0.25 ZFL97A 

1.33 34 0.50 0.29 N/A 0.50 1.06 0.17 6 0.25 ZFL912A 

1.33 34 0.52 0.29 0.17 0.56 1.06 0.17 6 0.25 ZFL914A 

1.33 34 0.65 0.50 0.50 N/A 1.06 0.17 6 0.25 ZFL919A 

1.33 34 0.65 0.29 0.17 0.75 1.06 0.17 6 0.25 ZFL19NSA 

2.125 54 0.51 0.47 N/A N/A 1.63 0.27 4 0.50 ZFL2150A 

2.125 54 0.70 0.47 0.17 0.76 1.63 0.27 4 0.50 ZFL2175A 

2.125 54 0.95 0.47 0.17 1.00 1.63 0.27 4 0.50 ZFL2110A 

2.75 70 0.52 0.5 0.21 0.57 2.31 0.27 6 0.75 ZFL14A 

2.75 70 0.96 0.5 0.21 1.01 2.31 0.27 6 0.75 ZFL25A 

2.75 70 1.46 0.5 0.21 1.50 2.31 0.27 6 0.75 ZFL38A 

2.75 70 1.58 0.5 0.21 1.63 2.31 0.27 6 0.75 ZFL41A 

2.75 70 1.58 0.5 0.39 1.75 2.31 0.27 6 0.75 ZFL45A 

3.375 86 1.44 0.63 0.22 1.51 2.85 0.34 8 1.00 ZFL3315A 

3.375 86 1.94 0.63 0.22 2.00 2.85 0.34 8 1.00 ZFL3320A 

4.5 114 2.00 0.69 0.37 1.96 3.63 0.34 8 2.00 ZFL50A 

4.5 114 2.41 0.69 0.37 2.50 3.63 0.34 8 2.00 ZFL64A 

4.5 114 2.68 0.69 0.37 2.76 3.63 0.34 8 2.00 ZFL70A 

4.625 117.5 2.44 0.75 0.37 2.51 4.03 0.34 10 2.50 ZFL4625A 

4.625 117.5 2.94 0.75 0.37 3.00 4.03 0.34 10 2.50 ZFL463A 

6 151.5 3.91 0.78 0.44 4.00 5.13 0.34 16 3.50 ZFL100A 

6.75 171.5 3.87 0.84 0.46 4.00 5.97 0.34 18 5.00 ZFL6740A 

6.75 171.5 4.93 0.84 0.46 5.00 5.97 0.34 18 5.00 ZFL6750A 

8 202.5 5.89 0.88 0.50 6.00 7.12 0.34 20 5.50 ZFL150A 

10 254 7.89 0.97 0.50 8.01 9.13 0.34 24 7.50 ZFL200A 

12 305 9.87 1.02 0.50 10.02 11.18 0.34 32 10.00 ZFL250A 

13.25 337 9.86 1.12 0.50 10.02 12.06 0.39 30 18.00 ZFL1310A 

13.25 337 10.63 1.12 0.50 10.76 12.06 0.39 30 14.00 ZFL1375A 

14 356 11.75 1.12 0.50 12.02 12.81 0.39 30 13.00 ZFL1412A 

14.25 362 11.89 1.18 0.63 12.01 13.15 0.41 36 19.80 ZFL300A 

Imperial 



057

Imperial 



316LN Rotatable Bored Flanges (FRL Series) 

316LN Rotatable Bored Flanges 




or to certain specific sizes of component. 





tube sizes. 




Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 

Tube Rot' Tube Bolt 

Clear Flange Land Counter Counter Hole Bolt No. of Shipping 

OD Bore Thickness Thickness Bore Bore PCD Hole Bolt Weight 

inch mm A B C D E F Diameter Holes lb Order Code 

1.33 34 0.26 0.29 N/A 0.26 0.76 1.06 0.17 6 0.25 ZFRL97A 

1.33 34 0.52 0.29 0.17 0.56 0.76 1.06 0.17 6 0.25 ZFRL914A 

1.33 34 0.65 0.50 0.50 N/A 0.76 1.06 0.17 6 0.25 ZFRL919A 

2.125 54 0.51 0.47 N/A N/A 1.10 1.63 0.27 4 0.50 ZFRL215A 

2.125 54 0.70 0.47 0.17 0.76 1.10 1.63 0.27 4 0.50 ZFRL217A 

2.125 54 0.95 0.47 0.17 1.00 1.10 1.63 0.27 4 0.50 ZFRL211A 

2.75 70 0.52 0.50 0.21 0.57 1.69 2.31 0.27 6 0.75 ZFRL14A 

2.75 70 0.96 0.50 0.21 1.01 1.69 2.31 0.27 6 0.75 ZFRL25A 

2.75 70 1.46 0.50 0.21 1.50 1.69 2.31 0.27 6 0.75 ZFRL38A 

2.75 70 1.58 0.50 0.21 1.63 1.69 2.31 0.27 6 0.75 ZFRL41A 

3.375 86 1.44 0.63 0.22 1.51 2.07 2.85 0.34 8 1.00 ZFRL335A 

3.375 86 1.94 0.63 0.22 2.00 2.07 2.85 0.34 8 1.00 ZFRL332A 

4.5 114 2.00 0.69 0.37 1.96 2.80 3.63 0.34 8 2.00 ZFRL50A 

4.5 114 2.41 0.69 0.37 2.50 2.80 3.63 0.34 8 2.00 ZFRL64A 

4.5 114 2.68 0.69 0.37 2.76 2.80 3.63 0.34 8 2.00 ZFRL70A 

4.625 117.5 2.44 0.75 0.37 2.51 3.10 4.03 0.34 10 2.50 ZFRL462A 

4.625 117.5 2.94 0.75 0.37 3.00 3.10 4.03 0.34 10 2.50 ZFRL463A 

6 151.5 3.91 0.78 0.44 4.00 4.13 5.13 0.34 16 3.50 ZFRL100A 

6.75 171.5 3.87 0.84 0.46 4.00 5.10 5.97 0.34 18 4.50 ZFRL674A 

6.75 171.5 4.93 0.84 0.46 5.00 5.10 5.97 0.34 18 4.50 ZFRL675A 

8 202.5 5.89 0.88 0.50 6.00 6.13 7.13 0.34 20 5.50 ZFRL150A 

10 254 7.89 0.97 0.50 8.01 8.15 9.13 0.34 24 7.50 ZFRL200A 











Example ZFL4A (plain bolt holes) becomes 

ZFL4TA (tapped bolt holes). 

Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 


316LN Fixed Blank Flanges (FL Series) 

316LN Fixed Blank Flanges 

Flange Bolt Hole No. of Shipping 

OD Thickness PCD Bolt Hole Bolt Weight 

inch mm B F Diameter Holes lb Order Code 

1.33 34 0.29 1.06 0.17 6 0.2 ZFL90A 

2.125 54 0.47 1.63 0.27 4 0.5 ZFL21A 

2.75 70 0.50 2.31 0.27 6 0.9 ZFL2A 

3.375 86 0.63 2.85 0.34 8 1.5 ZFL3A 

4.5 114 0.68 3.63 0.34 8 2.9 ZFL4A 

4.625 117.5 0.75 4.03 0.34 10 3.0 ZFL46A 

6 151.5 0.78 5.13 0.34 16 6.6 ZFL6A 

6.75 171.5 0.84 5.97 0.34 18 10.0 ZFL67A 

8 202.5 0.88 7.13 0.34 20 12.0 ZFL8A 

10 254 0.97 9.13 0.34 24 21.0 ZFL10A 

12 305 1.02 11.18 0.34 32 35.0 ZFL12A 

13.25 337 1.12 12.06 0.39 30 40.0 ZFL1325A 

14 356 1.12 12.81 0.39 30 44.0 ZFL1400A 

14.25 362 1.18 13.15 0.41 36 48.0 ZFL1425A 


Imperial 



059

Imperial 



316LN Rotatable Blank Flanges (FRL Series) 

316LN Rotatable Blank Flanges 













Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 

Flange Rotatable Bolt Hole No. of Shipping 

OD Thickness Tube Bore PCD Bolt Hole Bolt Weight 

inch mm B E F Diameter Holes lb Order Code 

1.33 34 0.29 0.76 1.06 0.17 6 0.2 ZFRL90A 

2.125 54 0.47 1.10 1.63 0.27 4 0.5 ZFRL28A 

2.75 70 0.50 1.69 2.31 0.27 6 0.9 ZFRL2A 

3.375 86 0.63 2.07 2.85 0.34 8 1.5 ZFRL33A 

4.5 114 0.69 2.80 3.63 0.34 8 2.9 ZFRL4A 

4.625 117.5 0.75 3.10 4.03 0.34 10 3.0 ZFRL46A 

6 151.5 0.78 4.13 5.13 0.34 16 6.6 ZFRL6A 

6.75 171.5 0.84 5.10 5.97 0.34 18 10.0 ZFRL7A 

8 202.5 0.88 6.13 7.13 0.34 20 12.0 ZFRL8A 

10 254 0.97 8.15 9.13 0.34 24 21.0 ZFRL10A 



Double-sides flanges are used for several different 

purposes including the spacing out of components 

from a flange. It is also possible to drill 

a hole from the outside diameter of the flange to 

the inside. If a thin tube and flange assembly are 

then welded in place, it allows you to introduce 

gases or have extra pumping around a component 

that either does not have any free ports or 

is limited on space. There is a version of the 70 

mm flange that has two KF ports added into 

its OD to permit this. Special versions of these 

flanges can be manufactured on request. 

Tapped Holes 

1.33 in = Tapped .160-32UNC 

2.125 - 2.75 in = Tapped .250-28UNF 

3.375 - 10 in = Tapped .312-24UNF 

13.25 - 14 in = Tapped .375-24UNF 


Double-sided Flanges 304L (F Series) and 

316LN (FL Series) 

Double-sided Flanges in 304L and 316LN 

Clear Flange Bolt No. of Shipping 

OD Bore Thickness Hole Hole Bolt Weight 

inch mm A B PCD Diameter Holes lb Order Code 

304L Material 

1.33 34 0.50 0.28 1.06 0.17 6 0.25 ZF914DA 

2.125 54 1.00 0.47 1.63 0.27 4 0.50 ZF211DA 

2.75 70 1.50 0.50 1.13 0.27 6 0.75 ZF38DA 

3.375 86 2.00 0.62 2.85 0.34 8 1.00 ZF335DA 

4.5 114 2.50 0.69 3.63 0.34 8 2.00 ZF64DA 

4.625 117.5 3.00 0.75 4.03 0.34 10 2.50 ZF462DA 

6 151.5 4.00 0.78 5.13 0.34 16 3.50 ZF100DA 

6.75 171.5 5.00 0.84 5.97 0.34 18 4.50 ZF675DA 

8 202.5 6.00 0.88 7.13 0.34 20 5.50 ZF150DA 

316LN Material 

1.33 34 0.50 0.28 1.06 0.17 6 0.25 ZFL914DA 

2.125 54 1.00 0.47 1.63 0.27 4 0.50 ZFL211DA 

2.75 70 1.50 0.50 1.13 0.27 6 0.75 ZFL38DA 

3.375 86 2.00 0.62 2.85 0.34 8 1.00 ZFL335DA 

4.5 114 2.50 0.69 3.63 0.34 8 2.00 ZFL64DA 

4.625 117.5 3.00 0.75 4.03 0.34 10 2.50 ZFL462DA 

6 151.5 4.00 0.78 5.13 0.34 16 3.50 ZFL100DA 

6.75 171.5 5.00 0.84 5.97 0.34 18 4.50 ZFL675DA 

8 202.5 6.00 0.88 7.13 0.34 20 5.50 ZFL150DA 


Imperial 



061

Imperial 



Double-sided Blank Flanges 304L (F Series) 

and 316LN (FL Series) 

The flanges described below are double-sided 

blank Conflat flanges. Please refer to drawing on 

page 061 for principal dimensions. 

Double-sided Blank Flanges in 304L and 316LN 

Flange No. of Shipping 

OD Thickness Bolt Hole Bolt Hole Bolt Weight 

inch mm B PCD Diameter 

304L Material 

Holes lb Order Code 

1.33 34 0.28 1.06 0.17 6 0.2 ZF90DA 

2.125 54 0.47 1.63 0.27 4 0.5 ZF21DA 

2.75 70 0.50 1.13 0.27 6 0.9 ZF2DA 

3.375 86 0.62 2.85 0.34 8 1.5 ZF33DA 

4.5 114 0.69 3.63 0.34 8 2.9 ZF4DA 

4.625 117.5 0.75 4.03 0.34 10 3.0 ZF46DA 

6 151.5 0.78 5.13 0.34 16 6.6 ZF6DA 

6.75 171.5 0.84 5.97 0.34 18 10.0 ZF67DA 

8 202.5 0.88 7.13 0.34 


20 12.0 ZF8DA 

1.33 34 0.28 1.062 0.172 6 0.2 ZFL90DA 

2.125 54 0.47 1.626 0.268 4 0.5 ZFL21DA 

2.75 70 0.50 1.13 0.268 6 0.9 ZFL2DA 

3.375 86 0.62 2.85 0.335 8 1.5 ZFL33DA 

4.5 114 0.68 3.628 0.335 8 2.9 ZFL4DA 

4.625 117.5 0.75 4.03 0.335 10 3.0 ZFL46DA 

6 151.5 0.78 5.127 0.335 16 6.6 ZFL6DA 

6.75 171.5 0.84 5.968 0.335 18 10.0 ZFL67DA 

8 202.5 0.88 7.125 0.335 20 12.0 ZFL8DA 



Zero Length Adaptor Flanges 304L and 316LN 

This type of flange is used to adapt from one 

flange size to another. The zero length indicates 

that it is no thicker than a standard flange 

(except the 1.33 inch to 2.75 inch OD adaptor). 

The larger flange OD has through bolt holes 

enabling ordinary nut and bolt kits to be used. 

The smaller flange OD has tapped holes so the 

bolts that are used must be shorter than normal. 

We offer bolt kits for both sizes of flange. 


Zero Length Adaptor Flanges, 304L and 316LN 

Flange 1 - Major Flange 2 - Minor Clear Bore Shipping 

OD Bolt Holes OD Bolt Holes Thickness A Weight 

inch mm inch to inch mm imperial 

304L Material 

inch mm inch lb Order Code 

2.75 70 0.27 to 1.33 34 .160-32 UNC 0.79 20 0.63 0.8 ZA3470A 

4.50 114 0.34 to 1.33 34 .160-32 UNC 0.69 17 0.63 3.0 ZA34114A 

10.00 254 0.34 to 1.33 34 .160-32 UNC 0.94 24 0.63 20.0 ZA34250A 

4.50 114 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 2.5 ZA70114A 

6.00 152 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 5.6 ZA7015A 

8.00 203 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 11.0 ZA7020A 

10.00 254 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 20.0 ZA7025A 

6.00 152 0.34 to 4.50 114 .312-24 UNF 0.94 24 2.50 4.7 ZA11415A 

8.00 203 0.34 to 4.50 114 .312-24 UNF 0.94 24 2.50 9.8 ZA11420A 

10.00 254 0.34 to 4.50 114 .312-24 UNF 0.94 24 2.50 18.0 ZA11425A 

8.00 203 0.34 to 6.00 152 .312-24 UNF 0.94 24 4.00 8.0 ZA15020A 

10.00 254 0.34 to 6.00 152 .312-24 UNF 0.94 24 4.00 16.0 ZA15025A 

10.00 254 0.34 to 8.00 203 .312-24 UNF 


0.94 24 6.00 15.0 ZA20025A 

2.75 70 0.27 to 1.33 34 .160-32 UNC 0.79 20 0.63 0.8 ZAL3470A 

4.50 114 0.34 to 1.33 34 .160-32 UNC 0.69 17 0.63 3.0 ZAL3414A 

10.00 254 0.34 to 1.33 34 .160-32 UNC 0.94 24 0.63 20.0 ZAL3425A 

4.50 114 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 2.5 ZAL7014A 

6.00 152 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 5.6 ZAL7015A 

8.00 203 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 11.0 ZAL7020A 

10.00 254 0.34 to 2.75 70 .250-28 UNF 0.94 24 1.50 20.0 ZAL7025A 

6.00 152 0.34 to 4.50 114 .312-24 UNF 0.94 24 2.50 4.7 ZAL1415A 

8.00 203 0.34 to 4.50 114 .312-24 UNF 0.94 24 2.50 9.8 ZAL1420A 

10.00 254 0.34 to 4.50 114 .312-24 UNF 0.94 24 2.50 18.0 ZAL1425A 

8.00 203 0.34 to 6.00 152 .312-24 UNF 0.94 24 4.00 8.0 ZAL1520A 

10.00 254 0.34 to 6.00 152 .312-24 UNF 0.94 24 4.00 16.0 ZAL1525A 

10.00 254 0.34 to 8.00 203 .312-24 UNF 0.94 24 6.00 15.0 ZAL2025A 


Imperial 



063

Imperial 



Klein Flange to Conflat Flange Adaptors (KA Series) 

Klein to Conflat Flanges Adaptors 

It is often necessary to join a Conflat flange to 

a Klein flange. This can be achieved easily by 

using an adaptor. The table below describes the 

range that we offer. Please note that some of the 

Conflat Flanges have tapped holes instead of 

through holes, which means that the connecting 

bolts cannot be inserted from the KF side of the 

flange when making the connection. The table 

also includes the order codes for the copper 

gasket, Viton ® o-ring and carrier, together with 

the flange clamp that is required to complete 

the seal. 

Conflat Length of Shipping 

OD Use Use Fitting L Weight 

mm inch Holes (1) Gasket to Klein O-ring Clamp mm inch lb Order Code 

34 1.33 Tapped ZCU19 to NW10KF KK10VCS KKF16CA 21 0.83 0.5 ZKA310TA 










(1) Please Note - Where bolt holes are tapped, bolts cannot be inserted from KF side of flange. 


Nut, Bolt and Washer Sets 

For reliable UHV seals, specially selected stainless 

steel bolt sets are recommended (see table 

on page 067). The materials are selected to 

match the expansion and contraction of the 

Conflat flanges during bakeout. This minimises 

the risk of vacuum leaks by differential expansion. 

We always recommend that bolts are lightly 

coated with an anti-seize thread lubricant during 

construction. This prevents seizure after a 

system bakeout. Be careful not to introduce any 

of this compound into the vacuum system as it 

will cause contamination. 

Alternatively we can supply silver-plated bolt 

sets. 

Anti-seize thread lubricant order code is ZTL 

(28 g tube). 

Nut Plate Sets 

Where access behind a flange is limited, or 

tapped flanges are required but not preferred, it 

is possible to use a nut plate set instead. Each set 

consists of two half-moon shaped metal pieces 

with tapped holes and set of bolt and washers. 

Access with a spanner is only required from the 

top as the plates are self locating behind the 

flange. If the threads become damaged, it is 

easy enough to replace the plate without having 

to touch the flange to which it is mounted. 

Nut plate sets are available for 34 mm (1.33"), 

70 mm (2.75"), and 114 mm (4.5") OD Conflat 

flanges. We always recommend that bolts are 

lightly coated with an anti-seize thread lubricant 

during construction. This prevents seizure after 

a system bakeout. Be careful not to introduce 

any of this compound into the vacuum system 

as it will cause contamination. 


Nut Plates 

Accessories 

Flange No of 

OD Nut No of No of 

inch mm Plates Bolts Washers Order Code 

1.33 34 2 6 6 ZNPS133 

2.75 70 2 6 6 ZNPS2 

4.50 114 2 8 8 ZNPS4 

Imperial 


Accessories 

065

Imperial 


Accessories 

General Accessories 

Thread Lubricant 

This may be used on external nuts and bolts; it 

is used to stop the nuts seizing to the bolts when 

the system is baked. It should be applied sparingly 

to the thread of the bolts during assembly. 

A small brush is an ideal way of applying the 

lubricant. 

Important - This lubricant is not UHV compatible 

so use it carefully, ensuring that no lubricant 

enters into the vacuum system. 

Order Code 

ZTL (28 g (1 oz) tube) 

Nylon Gloves 

To stop greasy fingers contaminating parts 

that are going inside the UHV system, we supply 

packs of clean nylon gloves. These should 

always be used when handling items. They 

should be regularly changed. 

Order Code 

ZNG10 (pack of 5 pairs) 





Copper Gaskets 

OD Comm- High Silver Alumin- Bolt 

inch Flange Type ercial Quality Annealed Plated Blank Viton ® ium Set(*) 

1.33 Standard Fixed or Rotatable ZCUC19 ZCU19 ZCUA19 ZCUSP19 ZCUB19 ZVIT19 ZAL19 ZAB7533 

1.33 Double Sided ZCUC19 ZCU19 ZCUA19 ZCUSP19 ZCUB19 ZVIT19 ZAL19 ZAB12533 

1.33 Tapped .160-32UNC ZCUC19 ZCU19 ZCUA19 ZCUSP19 ZCUB19 ZVIT19 ZAL19 ZAB0533S 

2.125 Standard Fixed or Rotatable - ZCU21 ZCUA21 ZCUSP21 - - - ZAB12521 

2.125 Double Sided - ZCU21 ZCUA21 ZCUSP21 - - - ZAB2215 

2.125 Tapped .250-28UNF - ZCU21 ZCUA21 ZCUSP21 - - - ZAB7821S 



2.75 Tapped .250-28UNF ZCUC38 ZCU38 ZCUA38 ZCUSP38 ZCUB38 ZVIT38 ZAL38 ZAB7827S 






4.5 Tapped .312-24UNF ZCUC64 ZCU64 ZCUA64 ZCUSP64 ZCUB64 ZVIT64 ZAL64 ZAB1254S 




6 Standard Fixed or Rotatable ZCUC100 ZCU100 ZCUA100 ZCUSP100 - ZVIT100 ZAL100 ZAB2256 

6 Double Sided ZCUC100 ZCU100 ZCUA100 ZCUSP100 - ZVIT100 ZAL100 ZAB2756 

6 Tapped .312-24UNF ZCUC100 ZCU100 ZCUA100 ZCUSP100 - ZVIT100 ZAL100 ZAB1256S 





8 Double Sided ZCUC150 ZCU150 ZCUA150 ZCUSP150 - ZVIT150 ZAL150 ZAB3258 




12 Standard Fixed ZCUC250 ZCU250 ZCUA250 ZCUSP250 - - ZAL250 ZAB312 

12 Tapped .312-24UNF ZCUC250 ZCU250 ZCUA250 ZCUSP250 - - ZAL250 ZAB212S 

13.25 Standard Fixed - ZCU13 ZCUA13 ZCUSP13 - - - ZAB313 


14 Standard Fixed - ZCU14 ZCUA14 ZCUSP14 - - - ZAB314 

14.25 Standard Fixed ZCUC300 ZCU300 ZCUA300 ZCUSP300 - - - ZAB31425 

(*) Most bolt kits come in packs of 25 except the ZAB312, ZAB212S which are in packs of 35 and ZAB314 which is a pack of 40. 

Imperial 


Accessories 

067

Imperial 


Accessories 

Zero Length Flange Accessories 

Zero Length Adaptor Accessories 

Zero Length Adaptor Order Code Flange 1 Gaskets Flange 2 Gaskets 

304L 316LN Copper Viton ® Bolt Set Copper Viton ® Bolt Set 

ZA3470A or ZAL3470A ZCU38 ZVIT38 ZAB12527 ZCU19 ZVIT19 ZAB0533S 














Conflat Range Gaskets 

To make a leak tight UHV seal between two conflat 

flanges, a gasket is required. OFHC (oxygen 

free high conductivity) copper is normally used 

as this sealing material as it is very clean, can easily 

be formed to shape, has a wide temperature 

range, and has a low outgassing rate. 

VG Scienta’s gaskets are manufactured from 

precision sheet material (to guarantee a consistent 

gasket thickness) and then inspected, cleaned 

and packed. 

Comprehensive Range of Gaskets in a 

Variety of Materials 

As OFHC copper gaskets are not always needed 

(or indeed suitable) for all requirements, we 

have a range of several different types of gasket 

materials. Some of these gaskets are used in 

specialised operating conditions, whereas others 

can be used for most of the general UHV 

applications. 

Ensure sealing surfaces are 

clean and dust free. 


Do not reuse gaskets, remove 

old gaskets with a gasket 

removal tool. 

Ensure FC flanges are evenly 

bolted down in a cross pattern. 

Use annealed gaskets for viewports 

and liquid feedthroughs. 

Gaskets 

Using Gaskets 

Use flange slots for leak checking. 

Gaskets 

069

Gaskets 

Superior Quality Copper Gaskets (CU Series) 

Superior Quality Copper Gaskets 

These gaskets are designed for use in high 

end UHV applications where total performance 

is required. These gaskets are inspected, fully 

cleaned and etched and then individually packed 

to ensure cleanliness. 

Flange Size Gasket Gasket Thickness Shipping 

OD OD ID A Qty per Weight 

mm inch mm inch mm inch mm inch Pack kg lb Order Code 

34.0 1.33 21.30 0.830 16.0 0.63 2.0 0.08 10 0.1 0.2 ZCU19 

53.8 2.12 32.80 1.290 25.4 1.00 2.0 0.08 10 0.1 0.2 ZCU21 

70.0 2.75 48.10 1.890 39.0 1.53 2.0 0.08 10 0.2 0.4 ZCU38 

85.0 3.35 61.60 2.420 51.1 2.01 2.0 0.08 10 0.5 1.1 ZCU54 

114 4.50 82.40 3.240 63.6 2.50 2.0 0.08 10 0.5 1.1 ZCU64 

117 4.63 91.60 3.600 76.2 3.00 2.0 0.08 10 0.6 1.2 ZCU46 

152 6.00 120.5 4.740 101.8 4.00 2.0 0.08 10 0.8 1.7 ZCU100 

171 6.75 141.5 5.570 127.0 5.00 2.0 0.08 5 0.8 1.7 ZCU67 

203 8.00 171.3 6.740 152.6 6.00 2.0 0.08 5 0.6 1.3 ZCU150 

254 10.0 220.1 8.700 203.4 8.00 2.0 0.08 5 0.7 1.5 ZCU200 

305 12.0 270.1 10.60 254.0 10.0 2.0 0.08 5 0.8 1.6 ZCU250 

305 12.0 272.7 10.70 254.2 10.0 2.0 0.08 5 0.8 1.6 ZCU250M 

336 13.2 294.0 11.59 276.0 10.87 2.0 0.08 5 1.0 2.2 ZCU13 

355 13.9 313.6 12.35 294.6 11.52 2.0 0.08 5 1.0 2.2 ZCU14 

362 14.2 321.1 12.60 305.0 12.00 2.0 0.08 1 0.2 0.4 ZCU300S 

362 14.2 321.1 12.60 305.0 12.00 2.0 0.08 5 0.8 1.6 ZCU300 

All dimensions are nominal and subject to production tolerances. 


Commercial User Copper Gaskets (CUC Series) 

Suitable for quantity gasket users, these gaskets 

are cleaned and individually packed to our normal 

UHV standards and supplied in large pack 

sizes. 




34 1.33 21.30 0.83 16.00 0.63 2.0 0.08 50 0.5 1.1 ZCUC19 

70 2.75 48.10 1.89 39.00 1.53 2.0 0.08 50 1.0 2.2 ZCUC38 

114 4.50 82.40 3.24 63.60 2.50 2.0 0.08 50 2.6 5.5 ZCUC64 

152 6.00 120.5 4.74 101.6 4.00 2.0 0.08 50 4.5 8.8 ZCUC100 

203 8.00 171.3 6.74 152.6 6.00 2.0 0.08 50 6.6 13.2 ZCUC150 

250 10 220.1 8.60 203.4 8.00 2.0 0.08 5 0.7 1.5 ZCUC200 

300 12 270.1 10.6 254.0 10.0 2.0 0.08 5 0.8 1.7 ZCUC250 

362 14.25 321.1 12.6 305.0 12.0 2.0 0.08 5 0.9 1.7 ZCUC300 



Commercial Use Copper Gaskets 

Gaskets 

071

Gaskets 

High Quality UHV Blank Copper Gaskets (CUB Series) 


High Quality Blank Copper Gaskets 

Blank copper gaskets are normally used for one 

of two main purposes, the first being to completely 

block off a port (to separate two chambers 

for instance) with an economic seal that is 

fully leak tight, takes up very little space, and can 

be easily removed. In the second instance the 

gasket can be bored by the user with a hole of 

a specific diameter. This allows pumping speeds 

and conductances to be 'tuned' without the 

expense of using a throttling valve. Blank copper 

gaskets are all individually packed. 

Flange Size Gasket Thickness Shipping 

OD OD A Qty per Weight 

mm inch mm inch mm inch Pack kg lb Order Code 

34 1.33 21.3 0.83 2.00 0.08 5 0.1 0.2 ZCUB19 

70 2.75 48.1 1.89 2.00 0.08 5 0.2 0.4 ZCUB38 

114 4.50 82.3 3.24 2.00 0.08 5 0.5 1.0 ZCUB64 



High Quality Annealed UHV Copper Gaskets 

(CUA Series) 

Annealed copper gaskets require a much lower 

sealing force to make a leak tight seal. They 

are normally used where it is important to 

limit the amount of force required when sealing. 

Recommended for use with items such as 

zero length viewports, gauge heads, and fragile 

ceramic feedthroughs. Annealed copper gaskets 

are all individually packed. 

High Quality Annealed Copper Gaskets 




34 1.33 21.3 0.83 16.0 0.63 2.0 0.08 5 0.1 0.2 ZCUA19 

53.8 2.12 32.8 1.29 25.4 1.00 2.0 0.08 5 0.1 0.2 ZCUA21 

70 2.75 48.1 1.89 39.0 1.53 2.0 0.08 5 0.1 0.2 ZCUA38 

85 3.35 61.6 2.42 51.1 2.01 2.0 0.08 5 0.2 0.4 ZCUA54 

114 4.50 82.4 3.24 63.6 2.50 2.0 0.08 5 0.2 0.4 ZCUA64 

117.5 4.63 91.6 3.60 76.2 3.00 2.0 0.08 5 0.5 1.0 ZCUA46 

152 6.00 120.5 4.74 101.8 4.00 2.0 0.08 5 0.8 1.7 ZCUA100 

171.5 6.75 141.5 5.57 127.0 5.00 2.0 0.08 5 0.8 1.7 ZCUA67 

203 8.00 171.3 6.74 152.6 6.00 2.0 0.08 5 0.7 1.5 ZCUA150 

254 10.00 220.1 8.70 203.4 8.00 2.0 0.08 5 0.8 1.7 ZCUA200 

305 12.00 270.1 10.60 254.0 10.0 2.0 0.08 5 0.8 1.7 ZCUA250 

305 12.00 272.7 10.70 254.2 10.0 2.0 0.08 5 0.8 1.7 ZCUA250M 

336.5 13.25 294.0 11.59 276.0 10.8 2.0 0.08 5 1.0 2.2 ZCUA13 

355.3 13.98 313.6 12.35 294.6 11.5 2.0 0.08 5 1.0 2.2 ZCUA14 

362 14.25 321.1 12.60 305.0 12.0 2.0 0.08 5 0.8 1.6 ZCUA300 


Gaskets 

073

Gaskets 

High Quality Silver Plated Copper Gaskets 

(CUSP Series) 

Silver-plated copper gaskets have two applications. 

They resist the external formation of copper 

oxide (the black ring seen on the outside of 

an old gasket) which is slowly produced when 

systems are baked to high temperatures. In 

some processes, this copper oxide can be a gross 

contaminant, and all precautions to prevent it 

High Quality Silver Plated Copper Gaskets 

getting into the UHV system must be taken. We 

recommend that silver-plated nuts and bolts are 

used to seal the flange when constant high temperature 

bakeouts are used. 

In the second instance, normal copper gaskets 

are attacked by some of the chemicals being 

used within the vacuum system, the MBE industry 

being an example of this. The silver plating 

offers an inert surface that is highly resistant to 

attack by many corrosive materials. 

VG Scienta’s silver plated gaskets are manufactured 

to very high standards of cleanliness, they 

are very carefully plated under controlled conditions 

and offer excellent resistance to ‘flaking’ of 

the silver coating during use. The plating process 

only uses silver; no nickel interlayer is used 

ensuring the highest quality seal (the gaskets are 

also non-magnetic). All silver-plated gaskets are 

individually packed. 




34 1.33 21.3 0.83 16.0 0.63 2.00 0.08 10 0.1 0.2 ZCUSP19 

53.8 2.12 32.8 1.29 25.4 1.00 2.00 0.08 10 0.1 0.2 ZCUSP21 

70 2.75 48.1 1.89 39.0 1.53 2.00 0.08 10 0.1 0.2 ZCUSP38 

85 3.35 61.6 2.42 51.1 2.01 2.00 0.08 10 0.2 0.4 ZCUSP54 

114 4.50 82.4 3.24 63.6 2.50 2.00 0.08 10 0.2 0.4 ZCUSP64 

117.5 4.63 91.6 3.60 76.2 3.00 2.00 0.08 10 0.5 1.0 ZCUSP46 

152 6.00 120.5 4.74 101.8 4.00 2.00 0.08 10 0.8 1.7 ZCUSP100 

171.5 6.75 141.5 5.57 127.0 5.00 2.00 0.08 5 0.8 1.7 ZCUSP67 

203 8.00 171.3 6.74 152.6 6.00 2.00 0.08 5 0.6 1.3 ZCUSP150 

254 10.00 220.1 8.70 203.4 8.00 2.00 0.08 5 0.7 1.5 ZCUSP200 

305 12.00 270.1 10.60 254.0 10.00 2.00 0.08 5 0.8 1.6 ZCUSP250 

305 12.00 272.7 10.70 254.2 10.00 2.00 0.08 5 0.8 1.6 ZCUSP25M 

336.5 13.25 294.0 11.59 276.0 10.87 2.00 0.08 5 1.0 2.2 ZCUSP13 

355.3 13.98 313.6 12.35 294.6 11.52 2.00 0.08 5 1.0 2.2 ZCUSP14 

362 14.25 321.1 12.60 305.0 12.00 2.00 0.08 5 0.8 1.6 ZCUSP300 



Where high bakeout temperatures (

Gaskets 

Aluminium Gaskets (AL Series) for Superior ZnSe 

MBE Operation 

Introduction to Aluminium Gaskets 

VG Scienta have developed a novel aluminium 

alloy gasket which, by virtue of its natural alumina 

film, provides an effective solution to the 

problems of chemical reaction in conventional 

copper gaskets. The benefits are many: 

• Up to 6 times longer vacuum life, decreasing 

the need for time consuming and expensive 

system breakdowns. 

• Inert to selenium totally removing contamination 

and electrical shorting problems 

found with copper selenide. 

• Novel aluminium alloy: pure aluminium gaskets 

are too soft and tend to leak if baked 

above +100 °C. 

• No leakage to +180 °C: repeatedly baked 

aluminium gaskets show no signs of leakage, 

enhancing long term system performance. 

Significant advances have been made in the 

development of new semiconductor devices 

(lasers and LEDs) based upon II-VI compounds 

Aluminium Gaskets 



mm inch mm inch mm inch mm inch Pack kg lb Order Code (1) 

34 1.33 21.3 0.84 16.2 0.64 2.5 0.098 5 0.1 0.2 ZAL19 

70 2.75 48.1 1.89 39.0 1.54 2.5 0.098 5 0.2 0.4 ZAL38 

114 4.50 82.4 3.24 63.6 2.50 2.5 0.098 5 0.5 1.0 ZAL64 

150 6.00 120.5 4.74 101.8 4.00 2.5 0.098 5 0.8 1.6 ZAL100 

200 8.00 171.3 6.74 152.6 6.00 2.5 0.098 5 0.6 1.2 ZAL150 

250 10.0 220.1 8.67 203.4 8.00 2.5 0.098 5 0.7 1.4 ZAL200 

300 12.0 270.1 10.6 254.0 10.00 2.5 0.098 5 0.8 1.6 ZAL250 


(1) A minimum order quantity may apply. 

such as ZnSe that will produce blue light. Until 

recently the high chemical reactivity of the selenium 

used has been a major limiting problem. 

Selenium is found to readily attack conventional 

copper gaskets. It is also found to readily attack 

silver-plated copper gaskets as well, both resulting 

in the formation of copper selenide. This 

results in the lifetime of the standard gaskets 

being substantially reduced by three causes. 

• The first is the production of leaks as the 

copper is eaten away. 

• The second is the contamination of samples 

and effusion cells by flakes of copper 

selenide. 

• The third is the shorting out of electrical 

components (ion gauges, quadrupole heads, 

etc.) by the electrically conducting copper 

selenide flakes. 

This range of aluminium gaskets is designed 

to overcome these problems to give significant 

gains in performance lifetime. 

Summary 

The only currently available UHV gasket material 

fully resistant to selenium is the special aluminium 

alloy gasket from VG Scienta. Already 

used in a growing number of working ZnSe 

MBE systems worldwide allowing significant 

operational benefits to be realised. 

Availability 

VG Scienta produce aluminium alloy gaskets in 

all sizes from NW19CF to NW250CF (34 mm 

OD to 300 mm OD flanges). A minimum order 

quantity may apply. 


Bolt Hole Orientations 

Many fittings are available with the option of 

having the fixed flange welded in one of two 

orientations - Inline or Straddled - the adjacent 

drawing shows the difference. Please examine 

your system’s mounting flange orientation 

before choosing your components. Flanges that 

are rotatable can be made to fit either mounting 

orientation. 

Special Requirements 

From time to time customers may require special 

constructions and/or materials that are beyond 

the specifications of our standard range of components. 

If you have such an application, please 

contact our technical support department or 


VG Scienta have been manufacturing Conflat flanges 

for over 40 years and were one of the first suppliers 

to the UHV industry. We have a very wide range of 

sizes and types of flanges produced in a number of different 

materials. These are fully compatible with other 

manufacturers' flanges up to NW250 size in terms of 

mating flanges together - thicknesses (dimension B in 

the drawing), gasket sizes, bolt hole number, pitch circle 

diameter (or PCD, dimension F in the drawing) and size 

etc., but there are some features of our flanges that you 

should be aware of when consulting this catalogue and 

ordering our products 


UHV Fittings Information 

Inline Orientation: 

Bolt holes in line with 

main axis of the 

chamber 

Straddled 

Orientation: 

Bolt holes straddle the 

main axis of chamber 

your local representative with details and we will 

be pleased to advise you of your best option. 

NW versus FC Designations 

VG Scienta has evolved and used its own FC designation to describe flange sizes. It is important to note that FC 

designation is not the same as the NW designation. FC generally refers to the outside diameter (OD) of a tube 

that is fitted to a flange; NW generally refers to the inside diameter (ID) or “clear bore” of the flange. 

Thus a VG Scienta FC41 flange has a clear bore of 38 mm and is therefore equivalent to an NW38 flange. 

Tube sizes - Imperial versus Metric Tube 

The tube counterbore diameters (dimension D in the drawing) of our flanges have been primarily governed by the 

availability of Imperial (inch) size tube in the UK; the USA still works with Imperial units and many of the original 

UK tube sizes are still used in the USA. 

In many cases there are standard sizes of metric tube that will fit our standard flanges - all critical dimensions of our 

standard flanges are quoted in millimetres, so please ensure that you check the tube counterbore diameter before 

ordering. In some cases we have included “true metric” versions of our flanges in the flange tables; otherwise the 

availability of metric versions is indicated against each flange part code. 

Tube Counterbore Depth or “Land Thickness” 

The land thickness (dimension C in the drawing) or set-back dimension is effectively the distance between the end 

of the tube that you insert into the flange, and the front face of the flange. For example, if you are fitting flanges to 

port tubes on a chamber, then this is the dimension that you need to take into account when calculating the overall 

port lengths. 

This dimension is not constant for all flanges, and varies from manufacturer to manufacturer. It is very important to 

take note of this when ordering bored flanges. 


Fittings 

077



UHV Fittings 

Introduction to UHV Fittings 

• All stainless steel construction 

• Wide range of styles 

• Wide range of sizes 

• UHV compatible 

• Bakeable to +450 ºC 

• Internal TIG welding (where possible) 

• Use from atmosphere to 1x10 -11 mbar 

UHV Fittings 

VG Scienta offer a comprehensive range of 

UHV fittings manufactured from 304L stainless 

steel to suit most customer applications. The 

large range of styles and sizes allows complicated 

chamber configurations to be built from 

a standard range of components enabling anything 

from a simple pumping line to a complete 

system to be made. 

Fittings are manufactured under closely controlled 

conditions resulting in very high quality 

components with low outgassing rates. 

The use of full internal welds wherever it is possible 

minimises the chances of virtual leaks and 

subsequent outgassing problems. The strong 

fully TIG welded construction of the UHV fittings 

allows for use (subject to their flange and 

gasket terminations) in the range from +450 ºC 

down to liquid nitrogen temperatures. 


A simple bored flange with welded tube stub. 

Not capable of being sealed on its own, it must 

be welded either into a hole bored on a chamber 

or to another tubulation to make custom manifolds, 

etc. All tubulations are fully UHV compatible 

and bakeable to +450 ºC. 


UHV Tubulated Flanges (BFT Series) 

Tubulated Flanges 

Wall Minimum Flange Shipping 

OD Dimension A Tube OD Thickness Bore (*) Alignment Weight 

mm inch mm inch mm mm mm inch and Number kg Order Code 

34 1.33 38 1.50 19.1 1.22 15.7 0.62 1 Fixed 0.5 ZBFT19 

34 1.33 38 1.50 19.1 1.22 15.7 0.62 1 Rotatable 0.5 ZBFT19R 

70 2.75 63 2.50 41.3 1.63 36.9 1.45 1 Fixed 0.8 ZBFT41 


114 4.50 105 4.12 63.5 1.63 58.9 2.32 1 Fixed 2.2 ZBFT64 


150 6.00 135 5.31 101.6 1.63 95.7 3.76 1 Fixed 5.0 ZBFT10 


200 8.00 167 6.56 152.4 1.63 146.5 5.76 1 Fixed 8.0 ZBFT15 


(*) Please Note - Minimum bore is determined by the manufacturing tolerances for ovality, outside diameter and wall thickness, so this 

dimension may vary. 



079



UHV Straight Connectors (BS Series) 

Straight Connectors 

A straight length of tube with a flange at both 

ends; one flange is fixed, the other rotatable. 

This allows it to align to the mounting flanges at 

either end. It can be used to build pumping lines 

or for mounting long items out of the vacuum 

system. All straight connectors are fully UHV 

compatible and bakeable to 450 ˚C. 

Wall Minimum Flange Shipping 

OD Dimension A Tube OD Thickness Bore (*) Alignment Weight 

mm inch mm inch mm mm mm inch and Number kg Order Code 

34 1.33 76 3.00 19.1 1.22 15.7 0.62 1 Fixed and 1 Rotatable 0.7 ZBS19 





(*) Please Note - Minimum bore is determined by the manufacturing tolerances for ovality, outside diameter and wall thickness, so this 

dimension may vary. 



UHV Elbows - Curved Versions (BE Series) 

Elbows are used to change the direction of 

pumping lines by 90 degrees. The curved elbows 

have a higher conductance and fewer internal 

welds when compared to the mitred versions. 

One flange is fixed, the other is rotatable. The 

fixed flange can be welded in place with its bolt 

holes in an inline or straddled orientation. 

The ZBE38R version is directly (dimensionally) 

replaceable with the range of VR40, CR40 and 

CRD40 right angle valves. This allows you to 

build pumping lines that can easily be modified. 

All curved elbows are fully UHV compatible and 

bakeable to 450 ˚C. 

Elbows - Curved Versions 

OD Dimension A Minimum Bore 

Shipping 

(*) Flange Alignment Weight 

mm inch mm inch mm inch and Number kg Order Code 

34 1.33 38 1.5 15.7 0.62 1 Fixed Inline and 1 Rotatable 0.7 ZBE19RI 

34 1.33 38 1.5 15.7 0.62 1 Fixed Straddled and 1 Rotatable 0.7 ZBE19RS 

70 .75 63 2.48 33.7 1.33 2 Rotatable 0.9 ZBE38R 

114 4.50 105 4.13 58.9 2.32 2 Rotatable 3.6 ZBE64R 

152 6.00 184 7.24 95.7 3.76 1 Fixed Inline and 1 Rotatable 7.0 ZBE10HRI 

152 6.00 184 7.24 95.7 3.76 1 Fixed straddled and 1 Rotatable 7.0 ZBE10HRS 

(*) Please Note - Minimum bore is determined by the manufacturing tolerances for ovality, outside diameter and wall thickness, so this dimension 

may vary. 



081



UHV Elbows - Mitred Versions (BE Series) 

Elbows - Mitred Versions 

Elbows are used to change the direction of 

pumping lines by 90 degrees. The mitred elbows 

are made by cutting and rewelding a tube. They 

allow the longer penetration of objects when 

compared to the curved versions. One flange 

is fixed in position, the other is rotatable. The 

fixed flange can be welded with its bolt holes 

in an inline or straddled orientation. All mitred 

elbows are fully UHV compatible and bakeable 

to 450 °C. 

OD Dimension A Minimum Bore 

Shipping 

(*) Flange Alignment Weight 

mm inch mm inch mm inch and Number kg Order Code 






may vary. 


UHV Flexible Connectors (MF series) Hydroformed 

Bellows 

Flexible connectors are used to compensate for 

any misalignment between flanges that have to 

be linked together. They are often also used as 

vibration dampers. Compared to an edge welded 

bellows, the hydroformed is less capable of 

taking up large movements for its relative size. 

It is however more robust and less expensive to 

manufacture. The MF series are supplied with 

one fixed and one rotatable flange. All hydroformed 

bellows type flexible connectors are fully 

UHV compatible and bakeable to 450 °C. 


may vary. 


Flexible Connectors - Hydroformed Bellows 

Free Compressed Shipping 

Length A Length Minimum Bore (*) Flange Alignment Weight 

mm inch mm inch mm inch mm inch and Number kg Order Code 

34 1.33 76 3.00 65 2.56 15 0.59 1 Fixed and 1 Rotatable 0.5 ZMF919 







083



UHV Flexible Connectors (MFE Series) Edge Welded 

Bellows 

Flexible Connectors - Edge Welded Bellows 

Flexible connectors are used to compensate for 

any misalignment between flanges that have to 

be linked together. They are often also used as 

vibration dampers. Compared to a hydroformed 

bellows, the edge welded bellows is capable of 

taking up large movements for its relative size. 

The MFE series are supplied with one fixed and 

one rotatable flange. All edge welded bellows 

type flexible connectors are fully UHV compatible 

and bakeable to 450 °C. 

Free Compressed Extended Minimum Shipping 

OD Length A Length B Length C Bore (*) Flange Alignment Weight 

mm inch mm inch mm inch mm inch mm inch and Number kg Order Code 

34 1.33 92 3.62 79 3.11 108 4.25 16 0.63 1 Fixed and 1 Rotatable 0.9 ZMFE919 




may vary. 


UHV Flexible Bellows Connectors (FX Series) 

This type of stainless steel bellows connector is 

used to connect over longer distances than the 

MF and MFE series. They are available with a 

range of mounting flanges and lengths to fulfill 

most applications. They can be joined together 

when longer distances are required. When fitted 

with conflat flanges they are fully bakeable and 

suitable for use to 10 -11 mbar. All of the flexible 

connectors with Conflat-type flanges are fully 

UHV compatible and bakeable up to 450 °C. 


Flexible Bellows Connectors 

Free Shipping 

OD Length A Flange Alignment Maximum Weight 

mm inch mm inch and Number Bakeout kg Order Code 

34 1.33 180 7.08 1 Fixed and 1 Rotatable 450 °C 0.1 ZFX19F 

34 1.33 500 19.69 1 Fixed and 1 Rotatable 450 °C 0.2 ZFX19F5 










085



UHV Tees (BT Series) 

Tees have 3 ports equally spaced at 90 degrees 

intervals to form a T-shape. The single flange at 

90° to the others is always a rotatable. On the 

straight tubulation, one of the flanges is fixed, 

the other is a rotatable. The fixed flange can be 

welded with its bolt holes in an inline or straddled 

configuration. The ZBT38 versions are 

directly replaceable with our VR and CR series 

of valves. This allows you to build pumping 

lines etc. that are easily modified. All tees are 

fully UHV compatible and bakeable to 450 °C. 


may vary. 

086 www.vgscienta.com 

Tees 

Flange Alignment Shipping 

OD Dimension A Minimum Bore (*) and Number Weight 

mm inch mm inch mm inch Rotatable Fixed kg Order Code 

34 1.33 38 1.5 15.7 0.62 2 1 Inline 0.8 ZBT19RI 

34 1.33 38 1.5 15.7 0.62 2 1 Straddled 0.8 ZBT19RS 

70 2.75 63 2.48 36.9 1.45 2 1 Inline 1.4 ZBT41RI 


114 4.50 105 4.13 58.9 2.32 2 1 Inline 4.0 ZBT64RI 


152 6.00 135 5.31 95.7 3.76 2 1 Inline 8.5 ZBT10RI 


203 8.00 167 6.57 146.5 5.76 2 1 Inline 3.0 ZBT15RI 

203 8.00 167 6.57 146.5 5.76 2 1 Straddled 13.0 ZBT15RS

A four way cross has 4 identical ports, each 

equispaced at 90 degrees to each other. On each 

straight tube one of the flanges is fixed, and 

the other is rotatable. The fixed flange can be 

welded with its bolt holes in an inline or straddled 

configuration. All four way crosses are fully 

UHV compatible and bakeable to 450 °C. 


UHV 4-way Crosses (BX4 Series) 

4-way Crosses 




34 1.33 38 1.5 15.7 0.62 2 2 Inline 0.9 ZBX419RI 

34 1.33 38 1.5 15.7 0.62 2 2 Straddled 0.9 ZBX419RS 

70 2.75 63 2.48 36.9 1.45 2 2 Inline 1.8 ZBX441RI 


114 4.50 105 4.13 58.9 2.32 2 2 Inline 5.0 ZBX464RI 


152 6.00 135 5.31 95.7 3.76 2 2 Inline 10.1 ZBX410RI 


203 8.00 167 6.57 146.5 5.76 2 2 Inline 15.0 ZBX415RI 



may vary. 



087



UHV 6-way Crosses (BX6 Series) 

6-way Crosses 

A 6-way cross has 6 identical ports, each equispaced 

at 90 degrees to each other. On each 

straight tube one of the flanges is fixed and the 

other is rotatable. The fixed flange can be welded 

with its bolt holes in an inline or straddled 

configuration. All 6-way crosses are fully UHV 

compatible and bakeable up to 450 °C. 




34 1.33 38 1.5 15.7 0.62 3 3 Inline 0.9 ZBX619RI 


70 2.75 63 2.48 36.9 1.45 3 3 Inline 1.8 ZBX641RI 


114 4.50 105 4.13 58.9 2.32 3 3 Inline 5.0 ZBX664RI 

114 4.50 105 4.13 58.9 2.32 3 3 Straddle 5.0 ZBX664RS 

152 6.00 135 5.31 95.7 3.76 3 3 Inline 10.1 ZBX610RI 


203 8.00 167 6.57 146.5 5.76 3 3 Inline 15.0 ZBX615RI 



may vary. 


To complement our range of fittings, we have 

a comprehensive range of accessories. These 

include items such as blank flanges, viewports, 

valves, copper gaskets, nut and bolt kits, thread 

lubricant, gloves and many more. 


Accessories for UHV Fittings 

Accessories for UHV Fittings 

OD Copper Viton Nut and Nut plate Blanking 

Item Flange Gasket Gasket Bolt Set Bolt Set (1) Set Viewport 

ZBFT, ZBS, ZBE, ZBX4 34 mm ZCU19 ZVIT19 ZM4B20 ZNPS133 or ZFC90 ZVPZ916 

ZBX6, ZMF and ZMFE. ZNPS133A 

ZBFT, ZBS, ZBE, 70 mm ZCU38 ZVIT38 ZM6B35 ZNPS2 or ZFC2 ZVPZ38 

ZBX4, ZBX6, ZMF ZNPS2A 

ZBFT, ZBS, ZBE, ZBX4, 

ZBX6, ZMF and ZMFE 

114 mm ZCU64 ZVIT64 ZM8B45 ZNPS4 ZFC4 ZVPZ64 

ZBT, ZBS, ZBE, 

ZBX4, ZBX6 and ZMF 

150 mm ZCU100 ZVIT100 ZM8B50 N/A ZFC6 ZVPZ100 

ZBT, ZBS, ZBE, 

ZBX4, and ZBX6 

200 mm ZCU150 ZVIT150 ZM8B60 N/A ZFC8 ZVPZ150 

(1) UNC bolt sets available on request, please contact your local representative. 



089

Special & 

Custom 

Cluster Flanges 

Cluster Flange: Fig. 1 

C No. of 

A B degrees D E Ports Order Code 

152 70 12 135 211 3 ZCLF1573 

152 70 12 135 248 4 ZCLF1574 

203 70 13 167 249 4 ZCLF2074 


Dimensions Order Code 

See Fig. 2 ZCLPA793 

See Fig. 3 ZCLF1596 

UHV Cluster Flanges 

Cluster flanges attach to existing chamber ports. 

They are used for upgrading or increasing the 

number of chamber ports available, enabling a 

greater number of feedthroughs or electrical, 

liquid, power or thermocouple services to be 

introduced to the chamber. Cluster flanges with 

angled ports can be attached to standard fittings 

such as four way crosses or tees. The focal point 

of the cluster angle intersects with the centre line 

of the cross or tee enabling a low cost chamber 

to be built from standard components. 


Custom Builds 

From time to time our customers require special 

constructions or materials that are beyond the 

specifications of our range of standard components. 

If you have such an application, please 

contact our technical support department or 

your local representative with details of your 

requirements. 


Custom Hardware 

Synchrotron dipole vessel Conflat flanges. 

Rectangular Conflat flanges. 

Custom 

091

Special & 

Custom

UHV Flanges and Fittings - VG Scienta

Create successful ePaper yourself

Delete template?

Save as template?