PE water supply pipe pressure test steps and related precautionsPE water supply pipe pressure test steps and related precautions
The overall operation of PE pipe construction includes pay-off, excavation, welding, pressure test, backfill (not used for excavation), and put into use. The PE pipe construction specification stipulates that the pipeline can be put into use only after the pipeline is completed and passed the pressure test. To standardize the operation process of pressure test, the following points of pressure test are described below for the reference of users and construction units. .
1. The test pressure of the pipeline is equal to the hydrostatic test of the pipeline. The test pressure is 1.5 times the pressure of the pipeline during normal operation. The test pressure should be within the nominal pressure range of the pipe.
For example: the tap water pipeline normally uses 1.0MPa (nominal pressure) pipe, the operating pressure is generally 0.4MPa, the pressure used in the pipeline pressure test is 0.4X1.5 = 0.6MPa,
Normal water temperature is required during pressure test;
Try to avoid pressure test under low temperature conditions. If the construction period requires pressure test, the pipeline needs to be covered. After the water temperature, surface temperature and pipe temperature are kept flat, the pressure should be suppressed.
2. When the pipeline is filled with water, slowly fill the water and open the exhaust valve. The purpose is to drain the gas and make the pipe body gradually adapt to the water injection pressure.
3. When the pipeline is boosted, the pressure should be gradually increased (0.1MPa-0.2MPa each time, and the interval of each time is 30 minutes), exhausted multiple times, and the test pressure is slowly increased to the specified value.
4. The pipeline should be covered accordingly before the pressure test, and the water flow direction (such as tee, elbow, water valve) should be consolidated to prevent the instantaneous impact of the water flow and the water hammer pressure from damaging the pipeline.
5. The pressure test of long-distance pipelines should be carried out in stages, and the length of the pipeline for the staged pressure test should be 500 meters.
6. After the pressure holding time of the pressure test pipeline is 1 hour, the test pressure can be judged as qualified if the test pressure does not drop more than 0.05MPa.
7. The pressure test of the pipeline should be carried out with an aqueous medium. It is not advisable to use a gas or other medium for pressure test.