Consolidated Tech Man - Holo-Krome

TABLE 20 HOLO-KROME SOCKET PRESSURE PLUGS — FLUSH (PTF) TYPE — 7/8 TAPER
HOLO-KROME HEXAGON SOCKET PRESSURE PLUGS — FLUSH
TYPE (PTF — 7/8). The Holo-Krome flush type plug is a plug having a
tapered thread (7/8" diametral per foot) extending its entire length and
designed to provide a flush condition with a standard taper-tapped hole
TABLE 20 DIMENSIONS — FLUSH TYPE — 7/8 TAPER
NOMINAL
SIZE
1/16
1/8
1/4
3/8
1/2
3/4
NOTES FOR TABLE 20
1. THREADS - Threads conform to ANSI B2.2 Dryseal Taper Pipe
Thread. Taper: 7/8" diametral per foot.
PITCH DIAMETER - The pitch diameter at the socket face is the
diametral equivalent of one-half thread larger than the pitch diameter
(E 1 ) of a standard pipe thread taper-tapped hole (3/4 diametral taper
per foot). This provides the basic point of thread interference to produce
a high pressure sealed joint.
2. THREAD CHAMFERS - Both ends of the plug shall be flat and
chamfered approximately 90° included; the chamfer shall extend
slightly below the root of the thread and the edge between flat and
chamfer may be slightly rounded.
3. LENGTH - The length of the plug shall be measured overall on a line
parallel to the axis.
4. SOCKETS - See Page 13 Table 11, for hexagon socket dimensions.
A slight chamfer, radius or countersink on hexagon sockets is permissible.
(3/4" diametral per foot). It achieves a high pressure seal through the
difference in taper, with dimensions precalculated to provide a higher
sealing load near the large end of the plug and the threads near the top
of the tapped hole. It is used in applications where high pressures are
encountered and where protrusion is undesirable.
D J
T G
L (3)
NOMINAL
O.D.
0.307
0.401
0.529
0.667
0.830
1.041
THREADS
PER
INCH
27
27
18
18
14
14
5/32
3/16
1/4
5/16
3/8
9/16
HEX SOCKET
SIZE
NOM.
0.156
0.187
0.250
0.312
0.375
0.562
KEY
ENGAGEMENT
MIN.
0.140
0.140
0.218
0.250
0.312
0.312
WALL
THICKNESS
OVERALL
LENGTH
MIN. MAX. MIN.
0.052
0.049
0.045
0.040
0.067
0.054
0.250
0.250
0.406
0.406
0.531
0.531
BASIC
PITCH
DIAMETER
AT SOCKET
FACE
5. IDENTIFICATION GROOVES - Six equally spaced identification
grooves are located equidistant between corners of hexagon socket
and edge of chamfer with no particular alignment with hexagon. On
1/16 - 27 plugs, three identification grooves are permitted because of
space limitations.
6. DESIGNATION - Each of the characters in the symbol has a definite
significance as follows:
P = Plug
T = Taper
F = Flush
7/8 = .875 inch taper per 12 inches
Applicable Standards and Specifications
ANSI B2.2
0.235
0.235
0.391
0.391
0.516
0.516
0.28253
0.37495
0.49366
0.62904
0.78103
0.99147
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