Untitled - Future Pipe Industries

7.0: Hydrostatic testing of pipelines
7.1: General
• The length of the test portion should not exceed 1600 ft. This should be controlled at the site. The test section length may
be progressively increased to 5,000 feet after several consecutive successful tests of 1,600 ft lengths, at the discretion of the
Engineer or Client.
Note: While it may be possible to test longer sections, it should be noted that detecting and isolating a leaky joint in a very
long test section is more difficult, particularly in the case of small leaks. In addition, the expenses incurred in filling and emptying
the line is substantial in a long test section.
• The backfilling must be carried out correctly according to section 6.2. Check if the compaction has been properly executed
in order to avoid displacement of the line during testing. The couplings must be left exposed at their topside for visual
inspection. The thrust blocks, which are part of the pressure test section, should be of permanent constructions and concrete
should be poured at least 7 days before testing.
• Check whether all testing apparatus are available and operational.
• The opened ends of a line must be sealed temporarily with GRP or steel/Cast iron end- caps. GRP testing end-caps can be
purchased from the Future Pipe Industries, Inc., with the pipes and the fittings. The end-caps should have an inlet and an outlet.
The inlet should be placed at the bottom of the end-cap at the low end of the test section, and the outlet at the top of the
end-cap at the high end. See figure 24 for a typical arrangement of a test section and apparatus. The approximate end thrust
force is given in table 11
Note: Test pressure of pipelines are related to the intended working pressure (PW) in the pipes and not to the rated pressure
class of the pipes (PN)
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