Diesel engine pump product improvement design and test
During the 300 h cold drag reliability test of Gasoline Portable Fire Pump diesel pump, the flange surface of the pump body cracked, the check valve at the oil outlet was worn, and the piston of the pump was worn seriously (one of the pumps was pierced by the ejection rod). In view of this phenomenon, designers have taken the following rectification measures.
A. Improve the material grade of pump body.
B. The piston of the pump is replaced by the machined part (A) instead of the stamped part (B) to improve the roughness and roundness of its outer circle, improve its surface hardness and ensure its reliability.
C. Put forward wear resistance requirements for check valve materials. The original triangular guided outer circle parts used in the oil pump (a, wear occurred in the test, strength and wear resistance can not meet the requirements) are changed to cylindrical guided outer circle parts (b); For raw materials, fixed-point procurement is proposed to improve the roughness of the outer circle, the flatness of the end face and other technical requirements to ensure its wear resistance.
D. Put forward stiffness requirements for diesel engine pump spring. The spring (a) with the number of turns 10. 5, the effective number of turns 8. 5 and the diameter of 2. 3mm is changed to the spring with the number of turns 9. 5, the effective number of turns 7.
The reliability test of the improved diesel pump assembly was conducted again on the Gasoline Portable Fire Pump. No cracks appeared in all parts of the pump body during 500 h of test operation, and the piston wear was within the requirements, but severe wear still occurred in the check valve at the oil outlet end. After analysis, the relevant technical personnel finally concluded that the fitting gap between the middle hole of the outlet pipe joint of the diesel engine pump and the outer circle of the check valve was too large, so the fitting gap was changed from the original 0 150 0 300 mm to 0 0500 0 015 mm. During this period, the structure of the filter cup of the diesel engine water pump was not reliable, so the structure was redesigned, code number was 05S2023, and 10 05S2023 oil pump samples were immediately trial-produced. The test results show that the fuel supply performance of the diesel engine water pump is significantly better than that of the 05S2022 oil pump, and the structural reliability of the filter cup is also improved.
The improved double-acting diesel engine water pump did not have any faults during the 1 000 hours of cold drag reliability test, and the wear of all parts was normal and all performance indexes still met the requirements.
The Gasoline Portable fire Pump dual acting diesel water pump has the advantages of compact structure, small shape, high working strength and strong oil supply ability, which can meet the requirements of increasingly compact engine design. At the same time, the overall requirements of the assembly parts of the diesel engine and water pump must be improved, including its materials, processing accuracy, connection strength and fit clearance, so as to meet the reliability, mean failure time and other related product technical requirements. After that, the diesel engine and water pump must also pay attention to the requirements of smooth oil route. Because the high-pressure diesel engine water pump is close to the exhaust pipe of the diesel engine, the temperature is high, so it should prevent the oil pump from breaking, damage, oil leakage and other problems caused by fire and other major economic accidents.
Post time: Jun-29-2022