GB/T 40377-2021 (English Version) PDF

Scope: This document specifies limit values, test procedures, mitigation measures and related information to evaluate the possibility of long-term disturbance of AC voltage between 16.7 Hz and 60 Hz and AC corrosion. This document applies to buried cathodically protected pipelines subject to AC traction systems and/or AC transmission lines. This document does not apply to safety issues related to AC voltage in pipelines. These safety issues are covered in other relevant standards and norms (such as EN50443). Note 1: This document discusses the possibility of AC corrosion of metal pipes caused by AC interference caused by resistive, inductive or capacitive coupling of AC transmission systems, and the maximum allowable limits for the effects of these interferences. It mainly considers the long-term influence factors in the normal operation of the AC power system. Note 2: In the presence of AC interference, the protection criteria given in ISO 15589-1 are not sufficient to demonstrate that steel is effectively protected from corrosion.

GB/T 40377-2021 Referenced Document

EN 50443 Effects of electromagnetic interference on pipelines caused by high voltage a.c. electric traction systems and/or high voltage a.c. power supply systems*， 2024-04-20 Update
GB 4793.1 Safety requirements for electrical equipment for measurement,control,and laboratory use.Part 1:General requirements
GB/T 10123 Corrosion of metals and alloys—Vocabulary*， 2022-04-15 Update
ISO 15589-1 Petroleum, petrochemical and natural gas industries - Cathodic protection of pipeline systems - Part 1: On-land pipelines

2021 GB/T 40377-2021 Corrosion of metals and alloys—Determination of AC corrosion—Protection criteria