PIPING PNEUMATIC TEST PROCEDURE
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– Purpose and Scope – PIPING PNEUMATIC TEST PROCEDURE
This procedure shall supplementary apply to the specified codes and standards
(mentioned below) for the performance of pressure testing of pressure piping with gases.
During the pressure test it will be determined whether the pressure-retaining walls are
leak-tight when exposed to the test pressure and whether any deformations occur which
are critical as regards safety.
– Applicable Codes, Rules and Standards
ASME B31.3
– Scheduling of the Pressure Test
Pressure testing shall be performed after completion of all operations on the
pressureretaining
wall, but prior to applying painting, insulation, rubber coating, brick –lining,
metallic liners and similar coating to the inside and outside wall.
– Test Method
Due to process reasons, the hydrostatic test is not suitable.
The pressure test shall be performed as pneumatic test only.
– Performance
The test pressures applied shall be 1.1 times the maximum operating pressure of the
respective line (refer to P&I diagram)
The Manufacturer establish pressure test loops reflected in the P & I diagram prior to
testing for approval by Mahler AGS .
Calibrated measuring instruments (pressure gauge) with a measuring range of 1,5 to 4
times the test pressure shall be used. For pneumatic tests 2 measuring instruments
working independent from each other shall be used.
The holding time is at least 30 min. Environmental temperature range shall be between
17°C – 45°C.
The test fluid shall be inert, oil-free and dry gas, non-flammable and non-toxic, normally
air or nitrogen.
After pressure test the residues of the foam-frothing agent to be washed off, to avoid
Corrosion.
Procedure
– preliminary check by 2,0 bar including visual examination of joints
– pressure to be increased by steps until leakage test pressure is reached
– leakage test by test pressure = 0,5 bar
– pressure to be increased by steps until pressure test =1,1 x design pressure, min. 30
minutes holding time by test pressure
– Test Results and Report
The requirements are fulfilled, if
– no inadmissible deformation are found and
– no formation of foam is detected on leakages during the pneumatic test; for nonmetallic
gaskets on pipe flanges uniformly occurring fine-pored foam (without local
formation of bubbles) is, however, admissible.
The accepted pressure test shall be confirmed in a test report by the manufacturer.
The test report shall indicate the tested equipment, test pressure, test fluid, test results
and date, test temperature and pressure gauge No. with calibration certificate and
pressure test chart .
PIPING PNEUMATIC TEST PROCEDURE