AAK Hydraulic Directional Control Cartridge Valve Zero Leakage

Yobachi, from Kenya, has not been working for a long time as a purchaser, and
encountered difficulties in the hydraulic directional control cartridge valve.
After 6 months of use, their hydraulic power unit has unstable operation.
During after-sales checking, it was judged that that the main seal of the
hydraulic directional control cartridge valve is worn, causing leakage and
equipment failure. However, the hydraulic directional control cartridge valve
manufacturer said that it had been nearly 1 year since the shipment, and he
needed to purchase new ones again. Yobachi explained that taking the time on
the delivery, transportation, assembly, equipment commissioning and inventory
into account, the actual service life of this batch of hydraulic directional
control cartridge valves was only 6 months. The boss was not satisfied that
Yobachi had found an unreliable manufacturer. He had to re-purchase the
hydraulic directional control cartridge valves with a service life of more than
1 year without leakage. Yobachi was under pressure.

Yobachi left a message on our website:
1. I browsed the AAK cartridge valve website on Google.
2. Can AAK hydraulic directional control cartridge valve have zero leakage? And
the service life is more than 1 year?
3. What is the time and cost of customizing the hydraulic directional control
cartridge valve?

This is the first time that AAK received an inquiry from Kenya about hydraulic
cartridge valves. I was a little cautious. After communication, it was learned
that he had met with an unreliable hydraulic cartridge valve manufacturer,
which made him very passive with the boss and customers. According to the
system hydraulic schematic diagram and the original drawing of the hydraulic
directional control cartridge valve provided by him, after the analysis, AAK
engineers found that it is not difficult to make this hydraulic directional
control cartridge valve as zero leakage. Yobachi seemed a little unconvinced. I
told him that in 2022, AAK customized 67 non-standard hydraulic cartridge
valves for customers, and made samples of total 112 models of cartridge valves
for new and old customers. Till now, there are no quality complaints. After 7
days, Yobachi requested AAK to make samples. After 40 days, AAK sent 20 samples
of hydraulic directional control cartridge valves.

3 weeks later, Yobachi only told us that the equipment installed with AAK
hydraulic directional control cartridge valve operated stably, and there was no
further news. On the first working day after our CNY holiday, he sent an order
for 380 hydraulic directional control cartridge valves. He said that AAK
hydraulic directional control cartridge valve has been in use for more than 1
year, without leakage, and the equipment performance is more stable. The boss
asked him to purchase in batches.

The leakage of the original hydraulic directional control cartridge valve is
mainly caused by the wear of the main seal, which leads to the leakage of the
pilot hole. The cover plate, valve spool, valve cage, O-ring, guide rod and
valve body of the pilot hole are all tricky. It is not difficult to make it
zero leakage, AAK improved the original structure of the hydraulic directional
control cartridge valve from 3 aspects:

1. The cover plate and valve body are connected by screws, the valve cage is
inserted in the valve body, the valve spool is installed in the valve cage, the
valve spool is located under the cover plate, and the bottom surface of the
valve spool cavity is equipped with a return spring.

2. The inner wall of the valve spool is installed with a sealing ring that can
prevent the leakage of the pilot port. The main seal adopts a soft and hard
composite seal structure. The O-ring is installed on the valve spool guide
cylinder, and the O-ring prevents the oil from flowing back to the tank from
the pilot hole.

3. The main seal of the hydraulic directional control cartridge valve adopts a
soft and hard composite seal structure to prevent leakage at the pilot hole and
the main seal.

AAK hydraulic directional control cartridge valve, no leakage, you can also try
it!

https://www.aakindustry.com/info-de , tail/directional-control-cartridge-valves-
aak4 , 91

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