等径三通+长径弯头组合管件的安全性能分析

An Analysis on the Safety Performance of the Combined Fittings of Straight Tees and Long Radius Elbows

采用有限元法分析了典型的组合管件——等径三通+长径弯头组合管件在内压作用下的力学特性和安全性能,并对其安全性做出了评价。结果表明,压力管道组合管件既安全又方便;不同转角半径对等径三通+长径弯头组合管件的塑性极限载荷有不同影响,其最佳三通转角半径与管外径之比为0.17～0.21;现有管件的塑性极限载荷估算公式不适用于组合管件,是偏危险的。

The mechanical characteristics and safety performance were analyzed of the typical combined fittings-combined fittings of straight tees and long radius elbows under the action of internal pressure using finite element method, and their safety performance was evaluated. The result shows that the combined fittings for pressure pipes were both safe and convenient. The different corner radii have different influences on the plastic limit load of the combined fittings of straight tees and long radius elbows, the ratio of the optimum corner radius of straight tees to the external diameter of pipe r/D = 0.17-0.21. The existing estimated formulae of the plastic limit load of fittings are not suitable for combined fittings, and are some dangerous.