AAK Hydraulic Relief Valve, High Pressure Resistant and Long Service Life

Last Monday, Yvonne ordered 1,000 hydraulic pilot operated relief valves and
stressed that all parameters should be in line with the hydraulic relief valve
samples of last year. It seems a little strange. After we sent the samples last
year, Yvonne said that the parameters were up to standard, but the plan
changed. She would no longer purchase this hydraulic pilot operated relief
valve. After several rounds of communication, it was learned that Yvonne
changed the manufacturer last year and had suffered a loss, so she returned to
AAK to make up the order.

Yvonne, from a Canadian equipment company, started cooperation with AAK last
year. At the beginning of last year, their company planned to develop a
hydraulic power unit, which needed to purchase a hydraulic pilot operated
relief valve. After a round of screening, Yvonne chose 3 hydraulic relief valve
manufacturers to test samples, and AAK was one of them. Finally, Yvonne placed
the order with the hydraulic relief valve manufacturer with lowest price. In
more than half a year, customers complained that the hydraulic pressure of the
equipment was unstable. The pilot operated relief valve in the system is used
as a safety valve, but the valve spool and valve body are worn and the
coaxiality is deviated, resulting in abnormal valve opening and sharp rise of
system pressure, resulting in equipment failure.

According to the feedback from the manufacturer of the original hydraulic
pressure relief valve, this hydraulic pilot operated relief valve needs to meet
the high-pressure working condition of 450bar and cannot withstand such high-
frequency use. It can only be guaranteed the service life of half a year, and
has to be replaced every half a year for after-sales service. The boss was not
satisfied with the half year service life of this manufacturer and asked to
change the hydraulic relief valve supplier. According to the records of the
after-sales department, Yvonne found that among the samples from 3 factories,
only the equipment installed with AAK hydraulic relief valve has no complaint
record. The service life of the other one was about 10 months, but AAK was
normal after 1 year. I told Yvonne that according to previous customer cases,
the 18 month service life of this type of hydraulic relief valve under 450bar
high pressure is not a problem, because we are benchmarking the service life of
2 million times of HAWE.

She also wants to know why the service life of AAK hydraulic pilot operated
relief valve is better than that of other factories? The selection of materials
is the key to resist 450bar high pressure. Generally, AAK selects A+ material
to replace the A material used by the international top brands. For example,
the 20crni2mov high carburized bearing steel imported from Germany, is used as
the valve spool of this hydraulic relief valve, combined with the carburizing
pretreatment process, through the secondary quenching + cryogenic treatment +
low temperature tempering process, it is cooled to 650 ~ 700 ℃ and then
discharged after it is 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, so the wear of valve spool is no longer worried.

Yvonne privately told us that the boss was very satisfied with her ability to
quickly solve problems. AAK hydraulic relief valve with a service life of 2
million times will be their fixed supplier in the future.

AAK hydraulic pilot operated relief valve, is high pressure resistant, with 2
million times of service life, you can also have a small try!

https://www.aakindustry.com/info-detai , l/hydraulic-relief-valve-aak263

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