whether the allowable deflection has been exceeded by use of a pull-through
device or a deflection measuring device.
a.
Pull-through device: This device shall be a spherical,
spheroidal, or elliptical ball, a cylinder, or circular sections
fused to a common shaft. Circular sections shall be so spaced on
the shaft that distance from external faces of front and back
sections will equal or exceed diameter of the circular section.
Pull-through device may also be of a design promulgated by the
Uni-Bell Plastic Pipe Association, provided the device meets the
applicable requirements specified in this paragraph, including
those for diameter of the device, and that the mandrel has a
minimum of 9 arms. Ball, cylinder, or circular sections shall
conform to the following:
(1) A diameter, or minor diameter as applicable, of 95 percent of
the average inside diameter of the pipe; tolerance of plus 0.5
percent will be permitted.
(2) Homogeneous material throughout, shall have a density greater
than 1.0 as related to water at 4 degrees C 39.2 degrees F, and
shall have a surface Brinell hardness of not less than 150.
(3) Center bored and through-bolted with a 6 mm 1/4 inch minimum
diameter steel shaft having a yield strength of not less than 483
MPa 70,000 psi, with eyes or loops at each end for attaching
pulling cables.
(4) Each eye or loop shall be suitably backed with a flange or
heavy washer such that a pull exerted on opposite end of shaft
will produce compression throughout remote end.
b.
Deflection measuring device: Sensitive to 1.0 percent of the
diameter of the pipe being tested and shall be accurate to 1.0
percent of the indicated dimension. Deflection measuring device
shall be approved prior to use.
c.
Pull-through device procedure: Pass the pull-through device
through each run of pipe, either by pulling it through or flushing
it through with water. If the device fails to pass freely through
a pipe run, replace pipe which has the excessive deflection and
completely retest in same manner and under same conditions.
d.
Deflection measuring device procedure: Measure deflections
through each run of installed pipe. If deflection readings in
excess of 4.5 percent of average inside diameter of pipe are
obtained, retest pipe by a run from the opposite direction. If
retest continues to show a deflection in excess of 4.5 percent of
average inside diameter of pipe, replace pipe which has excessive
deflection and completely retest in same manner and under same
conditions.
3.2.3
Tests for Pressure Lines
Test pressure lines in accordance with the applicable standard specified in
this paragraph, except for test pressures. For hydrostatic pressure test,
use a hydrostatic pressure 345 kPa 50 psi in excess of the maximum working
pressure of the system, but not less than 690 kPa 100 psi, holding the
pressure for a period of not less than one hour. For leakage test, use a
SECTION 02531
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