盾构主驱动聚氨酯密封系统高效冷却研究

Study on high efficiency cooling of polyurethane seal for shield main drive

针对常规盾构主驱动密封系统频繁失效的问题,提出了盾构主驱动聚氨酯密封系统形式。为保证聚氨酯密封长期使用温度低于70℃,通过试验与仿真方法,研究聚氨酯密封系统摩擦热及冷却效率。试验测得聚氨酯密封润滑状态下滑动摩擦系数及力学性能数据,进而通过仿真手段得到直径为7.45 m的密封,发热量为51 kW。在此基础上建立盾构密封系统仿真模型,进行共轭换热仿真计算,得到冷却流量对唇口温度的影响曲线。通过设计优化异形-低热阻冷却水套,实现强化传热,最终使盾构聚氨酯密封唇口温度达到70℃以内,为聚氨酯密封应用于大直径盾构提供了理论依据。

A polyurethane sealing system for the main drive of shield tunneling was proposed to address the frequent failure of the sealing system in conventional shield tunneling.To ensure that the long-term service temperature of polyurethane seal is below 70℃,the frictional heat and cooling efficiency of the polyurethane seal system were studied by experimental and simulation methods.The sliding friction coefficient and mechanical performance data of the polyurethane seal under lubrication were measured experimentally,and then the heat output of the 7.45 m diameter seal was obtained,which was 51 kW through simulation.Based on this,a simulation model of the shield sealing system was established,and conjugate heat transfer simulation calculations were performed to obtain the influence curve of the cooling flow rate on the lip temperature.Finally,through the design and optimization of a special-shaped and low thermal resistance cooling water jacket,enhanced heat transfer was achieved,and the temperature of the shield polyurethane sealing lip was ultimately achieved within 70℃,providing a theoretical basis for the application of polyurethane sealing to large-diameter shield tunneling.