AAK Hydraulic Cartridge Pressure Control Valve Spool Processing Skills

The local manufacturer who has cooperated for 5 years can't meet the precision
requirements of the hydraulic cartridge pressure control valve spool, and the
defective rate is up to 70%. They gave up 2 weeks after receiving the order.
After AAK took over, 3 targeted processing skills were used. The roundness of
the hydraulic cartridge pressure control valve spool accuracy could be less
than 0.0005, the finish less than Ra0.02, and the percent of pass was more than
95%. Nabulung was completely relaxed after receiving AAK samples of hydraulic
cartridge pressure control valves.

Nabulung is from Egypt. In the first half of this year, their engineer asked
him to purchase 8 hydraulic cartridge pressure control valve samples for the
development of new equipment. The roundness of the hydraulic cartridge pressure
control valve spool shall be less than 0.0005 and the finish shall be less than
Ra0.02. Nabulung realized that the spool was very difficult. He chose a local
hydraulic cartridge valve manufacturer who had cooperated with him for 5 years
to make samples. The manufacturer started to try samples. 2 weeks later, the
manufacturer gave up. The defective rate of the spool was as high as 70%, and
the accuracy was not stable.

Nabulung found AAK and sent us an email: I noticed the advantages and
characteristic processing technology of AAK in the production of valve spools.
Can AAK sample the roundness of valve spool less than 0.0005 and the finish
less than Ra0.02? After communication, we learned the high defective rate of
the original manufacturer of the hydraulic cartridge pressure control valve.
According to the drawings provided by Nabulung, the requirements for this spool
are indeed very individual, and the conventional production process does not
work, but AAK has some experience in spool production and can adjust the
process accordingly. After 36 days, AAK sent 8 samples of hydraulic cartridge
pressure control valves.

37 days later, Nabulung emailed us that their engineer was very satisfied with
AAK hydraulic cartridge pressure control valve samples, especially the stable
accuracy of the valve spool. He was worried for nearly 2 months, and finally he
could put it down. The roundness of AAK hydraulic cartridge pressure control
valve spool accuracy can be less than 0.0005, and the smoothness is less than
Ra0.02, which mainly comes from 3 unique processing methods:

1. Roughly turn the profile of the valve spool, leaving a margin of 0.15mm,
slotting, drilling, and straightening with deflection instrument to make the
bending less than 0.02N/m.

2. The valve spool shall be subject to heat treatment and rough grinding after
the hardness reaches HRC65. The center hole is used for high-precision cone
hole positioning, and then the ejector pin holes at both ends of the valve
spool are honed to make the roundness of the ejector pin hole less than 0.0005,
the finish is less than Ra0.02.

3. Cryogenic treatment, freezing treatment at - 65°C - 75°C for 2 - 2.5
hours, the residual austenite in the valve spool will be transformed into
martensite, and the toughness and wear resistance of the valve spool will be
improved by at least 2 times. Most manufacturers of hydraulic cartridge
pressure control valves ignore this link.

AAK hydraulic cartridge pressure control valve, has unique skills to process
the valve spool, you can also try a small order!

https://www.aakindustry.com/info-det , ail/pressure-control-valves-aak463

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