2022 first-class construction engineer Municipal Gold Test lit gas pipeline functional test, first-built academic master notes, long press and like + forward + evaluation continue to be updated, Wendang version click on my avatar and send a private message to me: 2022
(I) Functional test sequence of gas pipeline
Pipeline purge → partial backfill (the embedded pipe is backfilled to more than 0.5m above the pipe, leaving a weld) → Strength test → weld backfill (the pipeline has been backfilled to more than 0.5m above the pipe) → Strength test → Weld backfill (the pipeline has been backfilled to more than 0.5m above the pipe) → Strictness test.
(II) Pipeline purge
1. Before the pipeline and its accessories are assembled and tested, gas purging or pipe cleaning
(1) Steel pipes with nominal diameter ≥100mm: pipe cleaning → gas purging inspection.
(2) Other pipelines ( ductile iron pipeline, polyethylene pipeline, steel frame polyethylene composite pipeline, steel pipeline with nominal diameter 100mm or length 100m): gas purging.
2. Pipe ball Cleaning
(1) The purge ball should be carried out in the direction of the medium flow (purpose: to avoid the damage of the inner sleeve of the compensator ).
(2) The diameter of the pipeline must be of the same specification, and pipes of different pipe diameters should be disconnected for cleaning.
3. Gas Purge
(1) The length of the pipe should not exceed 500m per purge, and if the pipe exceeds 500m, it should be purged in sections.
(2) The purge results can be placed on the purge port with paper or white paint for inspection. If there is no rust on the target within 5 minutes, it will be considered qualified.
(III) Strength test
Backfill soil in buried pipelines should be backfilled to more than 0.5m above the pipe, and a welding interface should be left.
Test pressure
(1) P0.8MPa (high pressure A, high pressure B, sub-high pressure A pipeline):
Test pressure = 1.5P; the test medium is clean water, and the water pressure test is carried out.
(2) P≤0.8MPa (other pipes): test pressure = max{1.5P, 0.4MPa (steel pipe, polyethylene pipe (SDR11) or 0.2MPa (polyethylene pipe (SDR17.6))}; the test medium is compressed air, and the air pressure test is performed.
