AAK Hydraulic Cartridge Needle Valve 2 Million Times of Service Life

Muhammad is from a hydraulic equipment manufacturing company in Turkey. He has
been purchasing smoothly for 3 years, but stumped by the valve spool of a
hydraulic cartridge needle valve. At the beginning of last year, some of their
customers complained that the positioning of the paper cutter was incorrect
because of the leakage of the hydraulic cartridge needle valve. The original
manufacturer said that the hydraulic cartridge needle valve spool was worn due
to 24H operation of the equipment, which can only be replaced every 8 months,
and can only guarantee the service life of 1 million times. The boss was not
satisfied with the after-sales service of the original hydraulic cartridge
needle valve manufacturer and asked Muhammad to find a manufacturer with a
service life of no less than 2 million times.

Muhammad left a message on AAK website: Can you customize the hydraulic
cartridge needle valve with a service life of 2 million times? Especially, the
valve spool shall be absolutely wear-resistant. After communication, it was
learned that the original manufacturer's valve spool was out of use after 1
million times, and the boss asked him to find 3 factories to sample at the same
time. This hydraulic cartridge needle valve is a standard part of HydraForce,
and most hydraulic cartridge valve manufacturers have existing procedures. As
long as the production process of valve spool is further upgraded, the wear
resistance will be at least doubled. After 15 days, AAK sent 5 hydraulic
cartridge needle valves.

Last week, Muhammad sent a PO for 600 hydraulic cartridge needle valves. Their
engineers selected AAK hydraulic cartridge needle valves. In the PK among the 3
factories, AAK valve spool has the strongest wear resistance, and it is safe
for 2 million times.

Because the working condition of the equipment requires high wear resistance of
the valve spool, in view of this hidden danger, AAK hydraulic cartridge needle
valve spool is heat treated by 3 steps:

1. First of all, the stress relief heat treatment shall be carried out by
heating in stages. The heating temperature of the first stage is 380 ℃, and
the heat preservation shall be 1H after reaching the temperature. The heating
temperature of the second stage is 530 ℃, and the heat preservation shall be
45min after reaching the temperature. The heating temperature of the third
stage is 720 ℃, and the heat preservation shall be 30min after reaching the
temperature. The air cooling shall be 300 ℃, and then the air cooling shall be
conducted to room temperature.

2. Secondly, carry out 2 times of quenching, heat the valve spool to 800 ℃,
hold it for 2H, then immerse it in quenching oil, hold it at 65 ℃ for 40min,
then cool it to room temperature, and wash and dry it. The valve spool shall be
quenched for a second time, and the temperature shall be kept at 700 ℃ for 1H,
and then immersed in quenching oil. Hold at 85 ℃ for 55 min, then cool to room
temperature, and wash and dry.

3. Finally, place the valve spool in the tempering furnace, heat it to 420 ℃,
and keep it for 30min. Continue to heat to 585 ℃, keep it warm for 1H, cool it
to room temperature, and then conduct surface strengthening heat treatment,
heat it to 950-980 ℃, keep it warm for 10-15min, cool it to 550-600 ℃ with
water, cool it to 300-360 ℃ with oil, and finally air cool it to room
temperature.

After 3 steps of upgraded heat treatment process, the strength of the hydraulic
cartridge needle valve spool is increased by at least 50%, and it is quenched
twice to release the residual stress. The wear resistance and corrosion
resistance of the valve spool are improved, and the service life is guaranteed
to be 2 million times.

AAK hydraulic cartridge needle valve, the valve spool has 2 million times of
wear resistance, you can also try it!

https://www.aakindustry.com/info-detail , /cartridge-needle-valves-aak468

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