Analysis of the technical condition of weared hydraulic pump plungers

Currently, equipment from various manufacturers is installed in agricultural machinery, such as Danfoss, Bosch Rexroth, Hydromatik, Eaton, Edbro, Hagglunds, Hitachi, Hydroflex, Hydraulics. The paper presents an analysis of the technical condition of worn plungers of the Danfoss FR-L-090C hydraulic pump. The hydraulic devices of this company are installed on tractors and agricultural machinery of the Rostselmash group of companies and tractors of the Kirovsky Zavod group of companies. Danfoss manufactures a variety of devices, for example: hydraulic pumps, hydraulic motors, air conditioners, valves, distributors, control equipment, hydraulic power cylinders, etc. Analysis of the technical condition of the plungers consisted in conducting micrometric studies of parts and assessing the condition of the working surface. The measurement has been s carried out using a lever micrometer MR-25 0.002 GOST 4381-87. The condition of the worn-out working surfaces has been assessed using a magnifying glass. The plunger has been measured along three belts in two mutually perpendicular directions. The plungers have been previously degreased. Based on the results of processing the wear data, the average plunger size has been established, and the average plunger wear per side has been calculated. By assessing the state of the working surface, it is found that some areas have traces of abrasive (freiting) wear. To restore the plungers, it is proposed to use the technology of electrospark machining.