三峡升船机卧倒门支铰座螺栓联结载荷特性分析与强度设计

针对三峡升船机在试运行过程中卧倒门支铰座螺栓发生断裂故障，分析得出故障的主要原因是螺栓联结的预紧力矩（1 233 N·m）过小、A2-70-M36螺栓强度不够。基于此，提出了一种提高三峡升船机下闸首卧倒门支铰座螺栓联结可靠性的方法。首先，分别分析计算了升船机卧倒门在无水关门、无水开门、有水关门和有水开门四种工况下的液压启闭机油缸的作用力及支铰座联结螺栓的最大工作载荷，其中有水关门工况考虑了0.8，0.7，0.5 m三种壅水高，有水开门工况考虑了0.8，0.5，0.3 m三种水位降。然后，根据启闭机的额定输出力，反推得出有水关门时壅水高不超过0.7 m，有水开门时水位降不超过0.3 m；最后，根据残余预紧力条件，确定了预紧力矩为2 400 N·m；强度计算结果表明，选用10.9级M36螺栓时，卧倒门支铰座螺栓联结能够满足强度要求。维修后卧倒门运行良好，可靠性提高，这为三峡升船机下闸首卧倒门安全运行提供了技术依据。

Load characteristic analysis and strength design for joint bolts of support pivots of tumble gate of ship lift in the Three Gorges

Aiming at the fracture fault of the joint bolts of support pivots of tumble gate during the trial operation of ship lift in the Three Gorges, the main reason of the failure was analyzed and concluded that the pre-tightening torque 1 233 N·m was too small and the strength of the bolt A2-70-M36 was not enough. The method to improve the reliability of joint bolts of support pivots of lower head tumble gate of ship lift in the Three Gorges was proposed. Firstly, the lifting forces of hydraulic hoist cylinder and the maximum working loads of the joint bolts of support pivots were obtained under four working conditions including the gate closing, opening without water, closing and opening with water. In the working condition with water, different backwater heights of 0.8, 0.7 and 0.5 m were applied when the door was closed, and 0.8, 0.5, 0.3 m when the door was opened. Then, according to the rated output force of hoist, the backwater height was below to 0.7 m and 0.3 m in the actual closing and opening process respectively. Lastly, based on the norm of residual preload, the required pre-tightening torque was subsequently confirmed as 2 400 N·m. Strength calculation results indicated that selecting and using M36 bolt of class 10.9, the joint bolts of support pivots of tumble gate could meet the strength requirements. The operation of the tumble gate after maintenance shows that the calculation method is reasonable and can provide a technical basis for the safe operation of the lower head tumble gate of ship lift in the Three Gorges.