弯矩作用下补强圈对带压开孔管道强度性能影响的试验研究

Influence of Reinforcement Pad on Strength Behavior of Hot Tapping Pipe under Branch Moment

采用与带压开孔中相同的焊接工艺制造了有补强圈和无补强圈两台试验模型,并进行横向弯矩试验。结果表明:模型主管、支管和补强圈横向截面两侧的应力分布呈现反对称性,模型支管根部有明显的应力集中现象;补强圈改变了模型主管上的应力分布规律,主管上的应力集中区从支管和主管的相贯区转移到补强圈外边缘的焊缝附近;补强圈降低了模型的最大应力,提高了模型的承载能力,有补强圈模型的应力比降为无补强圈模型的1/2,但极限弯矩提高为无补强圈模型的1.45倍。

2 hot tapping models were fabricated using the hot tap welding technology. The models used to study the influence of reinforcement pad on the strength behavior of hot tapping pipe under branch moment. The results indicate that the stress distribution of pipe, branch and reinforcement show the bilateral symmetry in the transverse plane, the distribution of stress concentration on the branch close to pipe - nozzle intersection area; Reinforcement pad changes the distribution of stress on the main pipe, the distribution of stress concentration on the main pipe diverts from pipe- nozzle intersection to the outside edge of reinforcement pad. Reinforcement structure reduced the maximum stress of the model, increased the limit load of the model. Stress ratio of the model with reinforcement pad is 50% lower than the model with no - reinforcement pad, while the limit moment of the model with reinforcement pad is 45 % higher than the model without reinforcement pad.