Comparative Tests of the Impact of Modifications to the Hydrostatic Drive System of Blasting Utility Vehicle WS-153/173

The article presents the results of a comparative analysis of pressure characteristics in the hydrostatic drive systems of blasting utility vehicles WS-153/173 currently operated and developed for the purpose of loading explosive charges in underground ore mines. The two compared solutions are both designed on the basis of variable displacement pumps with LS (Load Sensing) control. In the first solution, such pumps power all of the hydraulic operating elements, and in the second solution some of the auxiliary elements are powered independently by an added fixed displacement pump, thus reducing both the number of hydraulic energy receivers and the maximum flow rate on the line powered by LS pumps. The article presents and discusses the different time-pressure curves as recorded in typical operating procedures during tests performed on both of the analyzed systems. It also investigates the impact of the introduced modifications on the operation of the analyzed hydrostatic systems. The results of these research and development works seem an interesting material, in which actual devices are used as a direct example of a method for improving the parameters of hydraulic systems with LS pumps by modifying the system architecture.