Evaluation of technical condition of round gear hydraulic pumps of tractor mounted hydraulic systems

Introduction. In the technical service enterprises, the reliable estimation of a technical condition of hydraulic gear pumps of tractor mounted hydraulic systems is a priority in introducing new repair processes. The absence of data of manufacturing plants on limiting wear of working surfaces of hydraulic pump details, when the decision on repair is taken, leads to the necessity of carrying out additional researches. In this regard, the purpose of work is to find the limit wear values for working surfaces of details of round gear hydraulic pumps. Materials and Methods. The laboratory tests of used round gear hydraulic pumps were carried out according to the method developed in the GOSNITI on the hydraulic bench of the KI-28097M-GOSNITI. The controlled parameter during tests is the pump delivery rate. Results. The results of laboratory bench and micrometer studies of used round gear hydraulic pumps are presented in the work. The mathematical model of pump delivery rate dependence on statistically significant independent factors is obtained. The limit values for wear of working surfaces of round gear hydraulic pump details are determined by the steepest ascent method on the received mathematical model. Discussion and Conclusion. According to the results of the input bench control of the used round gear pumps, 81% of the tested units were operated in the over-extreme limit state. The limit values for wear of working surfaces of round gear hydraulic pump details obtained by the steepest ascent method make it possible to make a conclusion about the necessity of their restoration in repairing at technical service enterprises.