AAK Hydraulic Relief Valve, Inner Hole Roughness Ra below 0.8μm

Half a year ago, David, an American customer, sent an inquiry to AAK about 500
pilot operated hydraulic relief valves. This hydraulic relief valve is
difficult to process the inner hole. Our cost accounting department gave a
reasonable price. 3 days later, David informed AAK that the price of the
hydraulic relief valve was 16% higher than that of other manufacturers and he
could only place the order with other hydraulic relief valve manufacturer. As
far as I know, there are not many manufacturers who can make this hydraulic
relief valve. The price provided by AAK this time should be very cost-
effective. As David is our old customer, we never quote prices
indiscriminately. I always believe that it is also a sign of dishonesty to
quote prices indiscriminately.

Last month, David asked again whether the hydraulic relief valve quoted last
year could maintain its original price. I asked him curiously, hasn't this
hydraulic relief valve placed an order yet? David truthfully told us that last
time, the pilot operated hydraulic relief valves purchased in another
manufacturer were reported by the users that the stability was poor and the
valve was often stuck. They decided to get replacements. David contacted the
original manufacturer of the hydraulic relief valves, but the manufacturer was
unwilling to offer replacements. Because there were too many complaints, David
did not dare to ask the original manufacturer to re produce, so he emailed AAK.

David was very cautious this time. He specially sent us 5 samples of hydraulic
relief valves from the original manufacturer. After receiving and checking, we
found that the inner hole of the hydraulic relief valve has a taper, the
processing size is not accurate, and the surface roughness Ra is as high as
1.6μm. The root cause of these problems is that the processing tool rotates
improperly, which also shows that the original manufacturer is not good at
processing this special inner hole. No wonder there are so many complaints. It
is wise for David to change the factory.

David was satisfied with our diagnosis of this hydraulic relief valve and asked
us to make samples as soon as possible. 1 week later, AAK sent the samples of
hydraulic relief valve, and David approved our samples at one time. They
specially compared AAK hydraulic relief valves with that of the original
manufacturer. Their engineers admired the inner hole processing of AAK, which
not only has no taper, but also has more than twice the accuracy of the
original manufacturer.

For the special inner hole of this pilot hydraulic relief valve, AAK adopts CBN
cubic boron nitride cutter from Sumitomo company of Japan to replace the
conventional ceramic cutter. Most hydraulic relief valve manufacturers dare not
use this cutter, which is not only costly, but also exquisite in operation.
After the program is set, the tool completely avoids the taper of the inner
hole. At the same time, for the machining of inner holes, we also customized
the CBN boring cutter of integral cemented carbide steel, which can ensure the
roughness value Ra below 0.8μm. Our technicians deliberately adjusted the
cutting parameters to: n=400r/min, f=0.08mm/r, which improved the production
efficiency and dimensional stability. AAK has never been stingy with the cost
to ensure the processing quality. For the inner hole processing with high
quality, AAK only uses the latest and most efficient cutting tools in the
industry.

AAK hydraulic relief valves most welcome customers with high quality. You are
welcome to give it a try and be repaid with AAK unique skills.

https://www.aakindustry.com/info-de , tail/hydraulic-relief-valves-aak249

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