GB/T 20657-2022 Active

This document provides the necessary calculation formulas and templates for various pipe performance characteristics, including:
——Pipe performance, such as tensile strength, internal pressure resistance, and external extrusion resistance;
——Minimum physical indicators;
——Upper threading torque;
——Product test pressure;
——Critical dimensions of products related to test and inspection standards;
——Critical dimensions of test equipment;
——Critical dimensions of samples.
For pipe performance calculation formulas, extensive background information on their development and application is provided, as detailed in Appendices A to J.
This document is applicable to pipes manufactured according to ISO 11960 or API Spec 5CT, ISO 11961 or API Spec 5D, ISO 3183 or API Spec 5L. Under careful circumstances, the formulas and templates in this document can also be used for other pipes. Pipes that undergo cold processing during manufacturing (such as cold-straightened pipes) are also included in the scope of this document. This document is not applicable to pipes that undergo cold processing after being finished products, such as expansion pipes and continuous oil pipes.
When using the performance calculation formulas in this document for line pipes and other pipes, these pipes are limited to being used as casing/tubing or in laboratories, and their heat treatment processes, straightening processes, and yield strengths must be carefully correlated with the closest casing/tubing products. Similar caution is required when using these formulas for drill pipe performance calculations.
By inputting pipe manufacturing parameters, this document and its formulas can calculate the expected performance of pipes according to ISO 11960 or API Spec 5CT, ISO 11961 or API Spec 5D, ISO 3183 or API Spec 5L. The calculation results of these formulas should not be interpreted as a guarantee of the manufacturing process. Manufacturers prod