法兰预紧力及拧紧力矩的计算方法探讨

ON CALCULATION METHOD OF FLANGE BOLT PRE-TIGHTENING FORCE AND TIGHTENING TORQUE

法兰的预紧是确保法兰连接系统密封、防止泄漏的重要环节,而如何确定法兰拧紧力矩则是法兰预紧过程中的核心问题。文章重点介绍了法兰、垫片、螺柱连接系统控制螺柱预紧力的常用方法;为保证法兰连接系统安全可靠,提出了一套合理选择螺柱拧紧力矩的计算方法,同时指出了国内外规范在选择法兰预紧力与屈服强度比方面的主要差异,并在此基础上提出了工程上切实可靠的选择定力矩扳手控制法兰预紧密封的方法。

The pre-tightening of flange bolts is an important factor to ensure the sealing effect and prevent leakage of the flange connection system,and how to determine the tightening torque of flange bolts is the core issue in the flange pre-tightening process.This paper highlights the common methods for controlling the pre-tightening force of the flange connection system.In order to ensure the safety and reliability of the flange connection system,the paper puts forward a set of calculation methods for reasonably selecting the bolt tightening torque.Meanwhile,it points out the main differences in the selection of flange pre-tightening force and yield strength ratio in domestic and foreign specifications.And on this basis,the paper proposes a practical and reliable method for selecting the constant torque wrench to control the flange pre-tightening and sealing in engineering.