I always remember an unusual inquiry email about hydraulic relief valve from Ellenburger, a Russian customer, at the beginning of this year. The email subject was "Don't reply if without ability and confidence", he should have been in trouble at other manufacturers. The content of the email was about testing 20 hydraulic relief valves, with detailed part processing drawings and parameter requirements attached. That was a hydraulic relief valve with high requirements, and the accuracy of valve hole is required to be within 2μM, the material hardness of the valve spool is HRC68, and the surface of the valve body is galvanized nickel alloy, which must withstand high pressure of 450bar. In addition, the durability test of the hydraulic relief valve must pass 2 million times. The requirements in terms of manufacturing quality, function and performance for this hydraulic relief valve is all clearly indicated.
After more than 3 hours of discussion by AAK engineers, I replied to Ellenburger that AAK was able to produce this hydraulic relief valve at a development cost of 2,500 US dollars. After the email was sent, there was no reply, and I didn't follow up. Because I believe there are few manufacturers who can make this hydraulic relief valve. For example, in Ningbo, the "hometown of hydraulic valves in China", perhaps only 3 factories have this technical ability.
3 months later, Ellenburger suddenly asked our bank account number. He wanted to pay us to sample the hydraulic relief valve. I was also a little confused. After several rounds of communication, it was learned that the hydraulic relief valve had been developed for half a year, he found more than 20 manufacturers, communicated with more than 300 emails in total, and paid the development cost for 3 times, but all failed, and his mood was extremely bad.
Ellenburger said that when he saw AAK reply that we can produce this hydraulic relief valve, his first feeling was that the manufacturer who responded so quickly should not be very good, so he ignored us. He thought that AAK would certainly follow up by email within a week, but to his surprise, AAK didn't send any email for a month, so he began to pay attention to AAK hydraulic valve slowly. In AAK website, he saw the stories between AAK and many customers, and some cases made him admire AAK very much, therefore, he believes that AAK is the ideal manufacturer of his samples this time. I was also moved by him and promised him that if AAK sample failed, I would be willing to return the development fee. At the same time, I also reminded him that if AAK could not get the hydraulic relief valve done successfully, there was no need to find other hydraulic relief valve manufacturers in Ningbo.
After 45 days, 20 samples of hydraulic relief valves were sent after passing the internal test. Last week, Ellenburger informed us by email that AAK hydraulic relief valve samples passed the test, and each parameter met the requirements. Although 2 million performance tests have not yet yielded results, he believes there will be no problem, because from the test process, the hydraulic relief valve samples of the other 3 factories are not at the same level as AAK's.
For the hydraulic relief valve with high requirements, AAK 3 major advantages are admirable to Ellenburger, and I believe most customers can't achieve it.
1. AAK selects 100Cr2 bearing steel and adopts carbonitriding heat treatment process. It is infiltrated for 13 hours at a high temperature of 820-830 degrees, then oil quenched, cryogenic treatment from -60 degrees to -70 degrees, and tempering treatment from +150 degrees to +160 degrees. The hardness is guaranteed to be HRC68 or above. Wear resistance, high pressure resistance and durability have a good foundation.
2. AAK hydraulic relief valve uses ultra-high hardness diamond reamers for valve hole processing, especially good at hard material grinding, complete grinding, no trace. The accuracy of valve hole is guaranteed to be within 1-2μm, the surface roughness reaches Ra0.2-0.3, and the coaxial accuracy data is unified.
3.AAK has experienced technicians who have been in the factory for more than 12 years and have 30 years of industry experience. There are specially assigned personnel and special machines, and the operation is flawless.
AAK hydraulic relief valve, produced with American materials, Swiss equipment, German knives, and by 30-year technicians, you can also have a small try!