Optimization of Cylinder Seal Structure and Leakage Fault Troubleshooting for Hydraulic Gate Hoists
液压启闭机油缸密封结构优化及泄漏故障排查分析

摘要

液压启闭机油缸长期承受高水头荷载、频繁启停、低速重载与潮湿腐蚀环境的共同作用，活塞杆密封、活塞密封 及静密封一旦出现选型失配、沟槽精度不足、偏载磨损或油液污染，容易形成外泄漏、内泄漏和保压漂移，进而影响 闸门启闭同步性与水工建筑物运行安全。本文依据现行液压启闭机设计、液压缸试验、往复密封沟槽和防尘圈沟槽标 准，分析油缸密封系统的载荷传递及失效机理，提出由重载防尘、缓冲减压、主密封、回油控制和导向支承组成的组 合密封优化方案，并构建“现象确认—边界隔离—压力复核—拆检验证—闭环验收”的泄漏故障排查流程。研究认为， 密封优化不能停留于更换密封圈，而应同步控制活塞杆直线度、表面粗糙度、导向间隙、油液清洁度与瞬态压力。通 过结构、材料、加工、装配及状态监测协同，可降低重复泄漏风险，为水利水电工程液压启闭机检修与技术改造提供 参考。

Abstract

Hydraulic gate hoist cylinders are subject to the combined effects of high water-head loads, frequent start-stop operation, low-speed heavy-load conditions, and humid corrosive environments over long-term service. Once rod seals, piston seals, and static seals suffer from improper selection, insufficient groove accuracy, eccentric-load wear, or oil contamination, external leakage, internal leakage, and pressure-holding drift may easily occur, thereby affecting the synchronization of gate opening and closing as well as the operational safety of hydraulic structures. Based on current standards for hydraulic hoist design, hydraulic cylinder testing, reciprocating seal grooves, and wiper ring grooves, this paper analyzes the load transfer and failure mechanisms of cylinder sealing systems. It proposes an optimized combined sealing scheme consisting of heavy-duty dust prevention, buffering and pressure reduction, primary sealing, oil return control, and guiding support, and constructs a leakage fault troubleshooting process of “phenomenon confirmation—boundary isolation—pressure recheck—disassembly inspection and verification—closed-loop acceptance.” The study argues that seal optimization should not remain limited to the replacement of sealing rings, but should also involve the coordinated control of piston rod straightness, surface roughness, guide clearance, oil cleanliness, and transient pressure. Through coordination among structure, materials, machining, assembly, and condition monitoring, the risk of repeated leakage can be reduced, providing reference for the maintenance and technical renovation of hydraulic gate hoists in water conservancy and hydropower projects.