隧道掘进机主驱动高压密封系统关键参数试验研究

为解决隧道掘进机主驱动高压密封技术难题，指导高压工况下密封系统参数设计，通过搭建5 m级主驱动密封试验台，采用静态试验与动态试验相结合的方法，验证密封试验台的可行性，并深入研究转速、承压状态与冷却水流量对唇形密封与聚氨酯密封2种高压密封系统运行温度的影响。结果表明： 1）静态试验下，高压密封系统逐级加压至2 MPa可保持稳定，验证了2种密封系统的高承压能力； 2）唇形密封与聚氨酯密封的动态试验显示，高转速会降低承压密封的稳定性，在高压下影响显著增强； 3）转速对密封系统温度有较大影响，与密封系统温升呈正相关，并且承压越高，密封系统温升越大； 4）2种密封系统在转速1.5 r/min附近可均衡系统稳定性与发热量要求，聚氨酯密封结构的冷却水流量控制在50 L/min较优。

Experimental Research on Key Parameters of Main Drive High Pressure Sealing System of Tunnel Boring Machines

To solve the technical problems of the main drive high pressure sealing of tunnel boring machines and provide guidance for the parameter design of the sealing system under high pressure conditions, a 5 m main drive sealing test platform is established. Then, the feasibility of the sealing test platform is validated using a combination of static and dynamic tests. Moreover, the influences of rotating speed, pressure, and cooling water flow on the temperature rise of two high pressure sealing systems of lip shape and polyurethane seals are investigated. The results indicate the following: (1) In the static test, the high pressure sealing system is pressurized sequentially to 2 MPa and then becomes stable, validating the high pressure bearing capability of the two sealing systems. (2) The dynamic experiment results of the lip shape and polyurethane sealing systems indicate that a high rotating speed will reduce the stability of seal pressure, and the influence is more significant under high pressure. (3) The rotating speed significantly influences seal temperature; moreover, there is a positive correlation with seal temperature rise. The higher the seal pressure, the greater the seal temperature rise. (4) A rotating speed of 1.5 r/min can balance the requirement of stability and calorific values of the two sealing systems. The cooling water flow of the polyurethane seal system is better controlled at 50 L/min.