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One method of restraining a pipeline is to provide a welded-on thrust collar or other dependable anchorage means on one or both sides of the point requiring restraint and to use concrete poured around the collar for support against undisturbed soil surrounding the pipe.
At a bend, the fitting and pipe ends would have to be of a restrained type, adequate to withstand total thrust involved. The required number of thrust collars would be dependent on the magnitude of the thrust force to be restrained and the allowable load per collar.
Thrust collars are also used in lieu of water stops on fabricated wall pipe for installation in load-bearing walls to resist thrust caused by internal pressure.
The allowable load per standard collar for the various sizes of pipe is tabulated below. Contact AMERICAN when greater loads are involved.

Thrust Collar Blocking Arrangement
ADIP Table No. 9-11
Pipe
Size
in. |
Collar
O.D.*
in. |
Collar
Thickness*
in. |
Weight
of Collar*
lbs |
Allowable
Load
Per Collar**
lbs |
| 4 |
6.80 |
.25 |
1 |
4,500 |
| 6 |
8.90 |
.25 |
2 |
9,300 |
| 8 |
11.05 |
.25 |
2 |
16,000 |
| 10 |
13.10 |
.25 |
3 |
24,000 |
| 12 |
15.20 |
.25 |
3 |
34,000 |
| 14 |
17.30 |
.25 |
5 |
46,000 |
| 16 |
19.40 |
.25 |
6 |
59,000 |
| 18 |
22.50 |
.38 |
15 |
75,000 |
| 20 |
24.60 |
.38 |
11 |
92,000 |
| 24 |
28.80 |
.38 |
13 |
130,000 |
| 30 |
36.00 |
.50 |
29 |
200,000 |
| 36 |
42.30 |
.50 |
35 |
290,000 |
| 42 |
50.75 |
.75 |
98 |
390,000 |
| 48 |
57.05 |
.75 |
111 |
510,000 |
| 54 |
66.06 |
1.00 |
231 |
650,000 |
| 60 |
70.11 |
1.00 |
246 |
745,000 |
| 64 |
74.17 |
1.00 |
261 |
847,000 |
Notes:
*Dimensions and weights of thrust collars furnished by AMERICAN but manufactured by others may vary from those shown in Table 9-11.
**These values are based on dead-end thrust due to 250 psi internal pressure. For higher allowable loads or pressures, check AMERICAN.
Thrust collars may be specified on ductile iron pipe with minimum pressure classes.
Thrust collars will be fabricated from steel.
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