TRANSDEV CATALOGUE 2018 MARCH.pdf

SEARCH
BACK TO MAIN CONTENTS
HARDWARE
Trapezoidal Screws & Nuts
Trapezoidal Screws
The TransDev range of rolled Trapezoidal Screws and nuts are manufactured
to a very high standard, yet supplied at very competitive prices. Quality
Steels C45 and Stainless 316 are used for the manufacture of the screws.
Nuts can be supplied in Steel and Bronze from stock. Plastic and Stainless
Steel nuts can also be supplied. Nuts are supplied in flanged, round and
hexagon forms. As well as our standard range of screws and nuts, we
can offer fully machined components to customer's specifications and
drawings. Right hand and left hand forms can be supplied as well as
multi-start forms.
The quality on rolled leadscrews accuracy starts from 0.10 mm
per 300 mm length of screw with straightness tolerances starting
from 0.20 mm per 300 mm length.
Other Belts
Materials
Steel used for Trapezoidal Screws
• Screw type KUE
C45 - 1.0503 Carbon Steel
- Surface hardness after
rolling approx. 250 HB
• Screw type KAF
AISI 316 (Inox A4) - 1.4401
Stainless Steel – Surface hardness
after rolling approx. 280 HB
Steel used in Nuts
• Nut types MLF, MZP, MES
EN 10277-3 11SMnPb37 –
1.0737 Steel with Sulphur,
Manganese and Lead
Bronze used in nuts
• Nut Types HSN,FFR
EN 1982 CuSn 5Zn 5Pb5-C
– CC491K Bronze with Zinc
and Lead 60-70 HB
• Nut types HBD
EN 1982 CuSn7Zn4Pb7-C – CC493K
Bronze with Zinc and Lead 65-75 HB
C45 and AISI 316 were chosen because,
in addition to their natural qualities
as good construction materials, after
rolling they give a very good surface
hardness and finish on the thread sides.
These two features are decisive factors
for qualitative appraisal of Trapezoidal
Screws, because they give very small
friction coefficients; much lower than
those obtainable with machined screws,
where other conditions such as speed,
load and lubrication are equal. Nut life
is therefore also increased.
Dimensions
H1= 0,5 P
s=
•
h3= H4 = H1 + ac = 0.5 P + ac
z = 0,25 P = H1/2
d3= d – 2 h3
d2= D2 = d – 2 z = d – 0.5 P
D2= d + 2 ac
ac= bottom play
es= top deviation for screw
0,26795 es
R1 max.= 0.5 ac
R2 max.= ac
d (nominal thread size
Z + (es/2)
d2 - es
h-3
d3
R2
SCREW
R1
(es/2)
S/2
p
30°
ac H1 ac
R2
NUT
D1
H4
D2
D4
T +44 (0)1202 675 555 F +44 (0)1202 677 466 E sales@transdev.co.uk transdev.co.uk 777