Experimental study on power matching of modular double pumping stations of tunnel drilling rig

In order to solve the problems of heavy weight, relocation and transportation of the power pumping station of tunnel drilling rigs, it is proposed to divide the pumping station through modular design, and adopt the solution of small-displacement, dual-power and dual-pump confluence, effectively reducing the transportation size and weight of a single pump station. A single-pump station or a double-pump confluence is chosen according to the working conditions to improve the flexibility of the drilling rig and reduce energy consumption. The load-sensing system has the advantages of energy saving, good load adaptability, and convenient speed regulation. However, when the dual-load-sensing pump system merges, the output power of the two pumps is unbalanced, and the output parameters of the drilling rig do not meet the design requirements, which are urgent problems to be solved. Through theoretical analysis, it is proposed that the difference of the feedback pipeline between the two load-sensitive pumps and the load-sensitive valve affects the power balance of the two pumps, and then the dynamic model of the dual-power dual-pump load-sensitive system is established. Based on the model, the pressure-flow characteristics of the dual-load sensitive pump system are dynamically analyzed, the influence of the feedback pipeline and pressure compensator on the power balance of the dual-pumping station is analyzed, and the power matching method of the dual-load-sensitive pump system is proposed. The theoretical analysis results are verified by the bench test. The results show that the pipeline difference has a great influence on the output characteristics of the dual-pump dual-dynamic load-sensitive pump confluence system. Setting damping in the feedback line and matching damping parameters according to the line can realize the basic balance of the output parameters of the two pumps. By fine-tuning the spring pre-compression of the pressure compensator, the system can achieve a better balance and eliminate the influence of pipeline differences. The problem of the unbalanced output power of the two pump stations is solved. The method has strong universality and application value, providing an important reference for the modular design of the hydraulic pump station of the tunnel drilling rig.