为解决国内LOVAT盾构机普遍存在的主液压系统故障的难题，对LOVAT盾构机主液压系统常见故障的发生原因进行分析，得出此类型盾构机主液压系统改造的技术措施，包括液压系统设计、管路压力损失验算和改造后系统部件的组装调试等。通过对主液压系统的改造，解决了主液压系统的现存故障，完善了主油箱液压系统的设计，可为类似系统改造积累经验。

The causes for the common malfunctions of the main hydraulic system of Lovat shield machines are analyzed. Technical measures to reform the main hydraulic systems of these shield machines, including the design of the hydraulic system, the calculation of the pressure loss in the hydraulic hoses, the assembly and debugging of the components of the hydraulic system after reforming, are determined. After the reform, the malfunctions of the main hydraulic system are solved and the design of the hydraulic system of the main hydraulic oil tank is improved. 