Corrosion protection testing leakage voltage
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When carrying out anti-corrosion treatment on pipelines, electric spark leak detectors are used to detect leaks in buried pipelines. When using such detectors, the leak detection voltage at the repair sites is 15 KV; so what is the leak detection voltage for the main body of the pipeline?
Generally, this is the same as the anti-corrosion coating for the same component; however, some supervisors or owner representatives are quite strict regarding the applicable standards. If it’s DIN30670, then it’s 25 kV.
SY/T0413-2002 specifies electric spark leak detection; the anti-corrosion coating on the pipes is rated at 25 kV, while that at the joints is rated at 15 kV
The original poster is right~~ there are standards
What the people upstairs said is all correct. However, the leak detection voltage is calculated based on the type and thickness of the pipeline’s anti-corrosion coating; if the leak detection voltage for repair joints is 15 kV, it should be the same for the main pipeline as well, and there are standards that specify this
Reply to 6# phil79: The repair strips are made of radiation-crosslinked polyethylene. For pipe diameters ≤400, the base material thickness is ≥1.2 mm and the adhesive layer thickness is ≥0.8 mm; for pipe diameters >400, the base material thickness is ≥1.5 mm and the adhesive layer thickness is also ≥0.8 mm. The anti-corrosion layer of the pipe body is made of extruded polyethylene, and it is much thicker than that of the repair strips – I can attest to this as I worked in field management for long-distance pipelines for a year, using pipes with a 25 kV rating
Reply to 7# Distant One: Of course, this 25KV value applies to the 3PE anti-corrosion coating. For the buried pipes in the ground at our company’s gate stations, epoxy coal tar pitch is used for anti-corrosion purposes, and the leak detection voltage in that case is quite low. We use an extra-strong anti-corrosion coating, which results in a leak detection voltage of only 6000V