For 240L flow rate and 450bar pressure resistance, the service life of hydraulic relief valve is more than twice that of the original manufacturer hydraulic equipment company. At the beginning of last year, the hydraulic station they sold to was complained by the customer in less than half a year. The oil temperature in the hydraulic station was abnormal, as high as 80 , and the efficiency of the whole hydraulic transmission was poor. The after sales service found that the hydraulic relief valve was stuck, which affected the load relief and caused the oil to heat up. The original hydraulic relief valve manufacturer believed that the jamming was caused by unclean hydraulic oil. After detecting the hydraulic oil, there was no abnormality. When disassembling the hydraulic relief valve, it was found that the contact surface between the valve spool and the valve hole was worn, which should be caused by the coaxiality deviation between the valve spool and the valve hole of hydraulic relief valve, resulting in the jamming. The original manufacturer agreed to replace it, but half a year later, the old problem happened again, and was criticized. had to find manufacturers with long service life of hydraulic relief valves. He contacted many manufacturers and found that most of them were not able guarantee a service life of over 1 year for the hydraulic relief valves with a maximum flow of 240L and a pressure of 450bar, but only 6 months. Finally, only 3 manufacturers were willing to test samples, including . engineers determined that the material selection was a key step according to the parameter requirements of the hydraulic relief valve. After 2 months, 30 samples of hydraulic relief valve were sent out. Last week, we received the PO of hydraulic relief valves from . He said that although was the latest to deliver the samples, in the service life test, the hydraulic relief valve samples provided by the 3 manufacturers showed that only had no abnormalities after a service life of more than 1 year. For this kind of customized, high demand and non-standard hydraulic relief valve, our 3 advantages are not available in most manufacturers . 1. The durability of hydraulic relief valve mainly depends on the material selection according to the working conditions. For this hydraulic relief valve, selects 20CrNi2MoV high carburized bearing steel pretreatment process, through secondary quenching cryogenic treatment low temperature tempering process, it is cooled to 650 ~ 700 and then discharged after being cooled to 450 ~ 500 The microhardness is 237 247 HV, and its wear resistance and contact fatigue performance are increased by more than 3 times. The heat treatment of this material is difficult to control, and most manufacturers cannot control it.
