AAK Hydraulic Pressure Reducing Valve Durability Exceeds German factory

Edmund from Germany has purchased hydraulic valves from AAK for more than 3
years. He emailed me a question this morning: the SiCr alloy steel pressure
spring is used in hydraulic pressure reducing valves, and its durability can
not reach 1million times or more? I asked him why he suddenly asked so? He
frankly told me that he had encountered problems when purchasing hydraulic
pressure reducing valves from Germany factory. At the same time, he also saw an
article of AAK that " For hydraulic pressure control valves that German
manufacturers were unwilling to solve, AAK used special spring to ensure a
service life over 1 year”, so he wanted to discuss it with me.

At the beginning of last year, the hydraulic pump of the excavator they sold
often had insufficient startup pressure. The problem lied in the hydraulic
pressure reducing valve of the hydraulic pump. The pressure of the hydraulic
system was unstable because the pressure spring of the hydraulic pressure
reducing valve was deformed. Since this excavator has been in use for less than
1 year but the hydraulic pressure reducing valves must be replaced. Edmund
contacted the local original manufacturer to replace several hydraulic pressure
reducing valves. The manufacturer replied that the hydraulic pressure reducing
valve was produced according to the standard, and the strength limit and
elastic limit of the piano wire used for the spring were in line with the
requirements. The problem was that the user's use frequency and working
pressure were too high, problem was caused by improper use. This time, they
were willing to replace it for free, and they would have to pay for it next
time.

Edmund is aware that if there is a complaint about one device, there may be a
complaint about the second one. This time, the replacement of the hydraulic
pressure reducing valve can only solve the current problem. Edmund began to
contact nearly 20 manufacturers of hydraulic pressure reducing valves. Most of
them said that the spring made of piano steel wire was the best material.
Edmund asked several factories to provide samples for testing to simulate the
high frequency and high pressure of excavators. After more than 2 months of
durability testing, the durability of the spring failed to pass 1 million
times, and basically began to be unstable after 400,000-600,000 times.

I joked that he found the right person to solve this problem. The spring of
piano steel wire is indeed a good material, but good materials do not
necessarily produce good finished products. We strictly follow 3 steps in the
selection of spring. The pressure spring of this hydraulic pressure reducing
valve really needs better materials to pass the durability of 1 million times.
AAK Hydraulic Valve began to innovate the pressure spring 1 year ago. At the
request of the customer, AAK technical team spent 24 days, tested samples for 6
times, compared 3 kinds of springs with good elasticity, and selected the
special SiCr alloy steel spring, which can pass the durability of 1 million
times. SiCr alloy steel spring has high temperature resistance, high rigidity,
anti relaxation and long service life. It can be used for 1 million times under
high stress conditions.

Edmund asked me to send samples. According to his hydraulic pressure reducing
valve drawings, I told him that samples could be sent in 4 weeks. I also told
him that using AAK hydraulic pressure reducing valve with SiCr alloy steel
pressure spring, he would no longer have to worry about complaints.

AAK hydraulic pressure reducing valve is protected by special SiCr alloy steel
spring under high stress, with a service life of 1 million times. You can also
have a small try!

https://www.aakindustry.com/info-detai , l/hydraulic-pressure-reducing-valve-
aak264

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