AAK hydraulic counterbalance valve with a service life of 2 million times

Patrick is the purchasing manager of a hydraulic equipment company in Italy. At
the beginning of last year, they sold a batch of shield machines to Portugal,
which were complained by customers within half a year. During the operation of
the shield machine, the grease pump at the tail of the shield had no pressure.
It was found that there was leakage in the hydraulic counterbalance valve of
the shield machine. After disassembly, it was found that the fitting clearance
between spool and valve hole of hydraulic counterbalance valve was worn. The
original hydraulic counterbalance valve manufacturer said that the wear of
hydraulic counterbalance valve was caused by the construction environment and
pressure requirements of shield machine, and the valve spool of hydraulic
counterbalance valve was made of 12L14 steel imported from the United States
with good wear resistance, which means there is nothing else he can do. Patrick
was helpless, and his engineers were not happy that he found such an
irresponsible hydraulic counterbalance valve manufacturer, requiring him to
find a manufacturer that has hydraulic counterbalance valves with a service
life of more than 2 million times.

Patrick contacted more than 20 hydraulic counterbalance valve manufacturers,
and AAK also received his drawings. Combined with the working condition
information, if the service life of this hydraulic counterbalance valve needs
to be more than 2 million times, material selection, processing accuracy,
durability testing, these 3 aspects are indispensable. We told Patrick that we
could test the sample directly. If the sample failed, we were willing to return
the development cost. 2 weeks later, Patrick paid $600 for the development and
informed that 3 hydraulic counterbalance valve manufacturers were testing
samples at the same time. He would only choose 1 manufacturer as their sole
supplier of this hydraulic counterbalance valve.

After 45 days, we sent the samples of hydraulic counterbalance valve. 2 months
later, Patrick wanted to order 500 hydraulic counterbalance valves at one time.
After more than half a year of comparison, AAK hydraulic counterbalance valve
was the only one that passed the durability test of 2 million times. His boss
was also very happy to find such a manufacturer. Patrick wanted to know how AAK
hydraulic counterbalance valve did in terms of material selection, processing
accuracy and durability test?

By doing 3 points, AAK differs from the peers, but also declares that there are
no peers for hydraulic counterbalance valve with a service life of 2 million
times.

1. AAK adopts 20CrNi2MoV high carburized bearing steel imported from Germany.
Combined with carburizing pretreatment process, through secondary quenching +
cryogenic treatment + low temperature tempering process, it is cooled to 650 ~
700 ℃ and put into the furnace. After cooling to 450 ~ 500 ℃, it is
discharged from the furnace. The microhardness can reach 237 ~ 247 HV, and its
wear resistance and fatigue resistance are improved by more than 3 times.

2. The precision honing machine imported from the United States, equipped with
diamond reamers, grinds 20CrNi2MoV steel. The grinding is complete and
traceless, providing a good guarantee for finishing.

3. The hydraulic counterbalance valve durability test equipment independently
developed by AAK meets the NFPA/T2.6.1 standard. It will be warehoused after 2
million times of fatigue test.

AAK hydraulic counterbalance valve, German materials, American equipment, more
than 2 million times of performance, you can also have a small try!

https://www.aakindustry.com/info-detai , l/hydraulic-counterbalance-valve-aak274

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