Page 401 - Trenchless Technology Piping Installation and Inspection

Inspection and QA/QC for Trenchless Installation and Replacement Methods 351

Direction of Bursting

Groundwinch® Air compressor

FIGURE 8.24 Pipe bursting. (Source: TT Technologies.)

Allowable Forces
See appropriate ASTM specification. As a guide, generally the pulling
force must not exceed the following limitations:
• For less than 16-in. OD, 10 tons
• For 16-in. OD or more, 20 tons
Allowable pulling force for all diameters must be determined
depending on the pipe material, size, wall thickness, manufacturer,
field conditions, pull distance, manhole integrity, bearing capacity of
soils, adjacent infrastructure, related equipment, cable strength, and
all other related considerations.

Pipe Dimensions

1. The range in pipe diameters used in this method varies with
the range in host pipe diameter. The upper size limit is based
on the capabilities of the installation equipment. See equip-
ment owner’s manual for more specific information.
2. New pipe must have a minimum standard dimension ratio
(SDR) of 11.
3. Pipe must be round. Steel pipe must have a roundness toler-
ance, so that the difference between the major and minor out-
side diameters must not exceed 1 percent of the specified
nominal outside diameter, or 0.25 in., whichever is less. Like-
wise, HDPE, ductile iron, and PVC pipe must have similar
roundness tolerances.