GB/T 20657-2011 in English

《GB/T 20657-2011石油天然气工业套管、油管、钻杆和用作套管或油管的管线管性能公式及计算》由TC355（全国石油天然气标准化技术委员会）归口，TC355SC9（全国石油天然气标准化技术委员会石油专用管材分会）执行，主管部门为国家标准化管理委员会。

Scope

This standard provides the necessary calculation formulas and templates for various pipe properties, including: -Pipe body properties, such as axial strength, internal pressure resistance and external pressure collapse resistance; -Minimum physical indicators; -Make-up torque ; - Product test pressure; - Product critical dimensions related to test testing standards; - Critical dimensions of test equipment; - Specimen critical dimensions. For the calculation formula of pipe material properties, a large amount of background information related to its development and use is provided. The formulas in this standard can be used for pipes produced according to ISO 11960 or API Spec 5CT, ISO 11961 or API Spec 5D, ISO 3183 or API Spec 5L, and select the appropriate formula according to the specific situation. These formulas and templates should be used with caution for other tubing materials. Products that undergo cold work during manufacture (eg, cold straightened pipe) are also covered by this standard. Cold-worked finished tubing, such as expandable tubing and coiled tubing, is outside the scope of this standard. The use of the performance calculation formulas in this standard for line pipe and other pipes is limited to the use of these pipes as casing/oil pipe or laboratory use, and the heat treatment process, straightening process and yield strength must be the same as those of the closest casing/oil pipe. Tubing products are carefully matched. The same care should be taken when these formulas are used for drill pipe performance calculations. By inputting pipe geometry, production process and material parameters, this standard formula can calculate the expected performance of pipes in ISO 11960 or API Spec 5CT, ISO 11961 or API Spec 5D, ISO 3183 or API Spec 5L. The calculation results of this standard formula cannot be understood as the guarantee of the production process. The manufacturer can produce oil pipes according to the production specifications including product size and physical and chemical properties. This standard design formula provides a reference value for users to understand the performance of tubing, which can be used for well design or research. This standard is not a design specification, it only provides formulas and templates for the performance calculation of tubing used in downholes. This standard does not provide any safety margins necessary for the loads that the pipe may experience or for acceptable design. The user determines the appropriate design loads and selects an adequate safety factor for a safe and efficient design. Design loads and safety factors should be selected based on historical experience, local regulatory requirements and specific well conditions. All the formulas and listed pipe performance data in this standard are assumed to be in a good environment, and the material performance meets the requirements of ISO 11960 or API Spec 5CT, ISO 11961 or API Spec 5D, ISO 3183 or API Spec 5L. Other environments may require additional analysis, as listed in Appendix D. This standard does not cover the seal strength of pipe joints and the performance of pipes under dynamic loads. All tensile stresses in this standard are positive. All tensile stresses in this standard are positive values.