Safety instrumentation
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For the flanged thermal resistors in gas pipelines connected with four bolts, is it necessary to use a bypass connection?
Clause 10.12.1 of the \"Code for Pressure Piping – Industrial Piping, Part 4: Fabrication and Installation\" (GB/T20801.4-2006) stipulates that for pipelines requiring static grounding, good electrical conductivity must exist between various sections of such pipelines. When the resistance value between each pair of flanges or threaded joints is greater than 0.03Ω, a wire bridge should be installed. In addition, Article 7.13.1 of the \"Code for Construction of Industrial Metal Piping Projects\" (GB 50235—2010) stipulates that for pipelines for which static electricity grounding is required, a bonding wire shall be installed when the resistance value between each pair of flanges or other joints exceeds 0.03 ohms. Whether to perform a bridge test should be done to check its resistance, ensuring that it is less than 0.03Ω. Based on the current inspection procedures, it is recommended to carry out an electrostatic bonding directly; experts won’t ask any questions either, which saves time
It needs to be done, but in most cases, more than 5 are required before a bypass cable is unnecessary; you should check the resistance values to see.
Then may I ask how to measure the resistance between flanges?