Hydraulic Cartridge Pressure Control Valve Zero leakage under High Pressure

Tarasios is a purchaser from a Greek hydraulic equipment manufacturing company.
He has been very smooth in purchasing. At the beginning of the year, their
customer customized a hydraulic power unit, and Tarasios chose a supplier that
had cooperated for 5 years to make samples for the hydraulic cartridge pressure
control valves. The commissioning of the prototype was not smooth. When the
load on the pressure reducing branch increased, the pressure at the working
port of the hydraulic cartridge pressure control valve increased and there was
oil leakage, which affected the pressure maintenance of the oil circuit. They
planned to add an accumulator to maintain the pressure, but the customer cannot
accept the additional cost. The boss asked Tarasios to purchase the hydraulic
cartridge pressure control valve without leakage under high pressure, but the
original manufacturer gave up. After seeking other hydraulic cartridge valve
manufacturers, it was fruitless. The boss was urging and Tarasios was worried.

Tarasios found the website of AAK hydraulic valves on Google, and noticed that
AAK has solved problems for customers many times, perhaps he saw the hope and
sent us an email to ask: Can AAK make the hydraulic cartridge pressure control
valve without leakage under the high pressure? We asked Tarasios to provide the
detailed drawings and the system schematic diagram. After analysis, AAK
engineers determined that only the original hydraulic cartridge pressure
control valve structure is optimized, it can meet the requirement of no leakage
under high pressure. Although it cannot be guaranteed to be success for100%, it
is 90% confident. After 50 days, AAK sent out 12 hydraulic cartridge pressure
control valves.

3 months later, Tarasios sent an email saying that the customer was satisfied
with the prototype and was ready to issue a regular order. Their engineers were
also satisfied with the function of AAK hydraulic cartridge pressure control
valves. When the pressure at the working port increased, there was no leakage.
AAK optimized the hydraulic cartridge pressure control valve from 3 aspects,
with 3 seals to ensure no leakage under high pressure.

1. The valve body of the hydraulic cartridge pressure control valve is provided
with a valve chamber, the side wall of the valve chamber is provided with a
liquid outlet, the upper end of the valve body is provided with a seal seat,
the upper end of the valve spool passes through the seal seat and is opposed to
the spring seat, the lower end of the valve spool is provided with a radially
projecting boss, which forms a conical seal with the lower end of the valve
body.

2. The valve cover is installed at the lower end of the valve body, and the
lower end of the valve spool extends into the valve cover, so that the inner
cavity of the valve cover is divided into a liquid inlet cavity and a return
cavity. The side wall of the liquid inlet cavity is provided with a liquid
inlet, and the side wall of the spring cavity is provided with a vent hole. The
outer wall of the seal seat and the inner wall of the upper end of the valve
body are sealed through a second seal ring.

3. The valve spool is provided with a throttling channel connecting the valve
cavity and the reflux cavity. A throttle port is formed between the valve spool
and the lower end of the valve body. The up and down movement of the valve
spool controls the opening of the throttle port. The outer wall of the lower
end of the valve spool and the side wall of the inner cavity of the valve cover
are sealed by a third sealing ring.

When the hydraulic cartridge pressure control valve is working, the pressure at
the outlet exceeds the pressure set by the regulating spring, and the pressure
at the outlet of the valve chamber increases to the point where the valve spool
can move up and the throttle between the valve chamber and the inlet chamber is
closed, without any leakage.

AAK hydraulic cartridge pressure control valve, 3 seals, no leakage under high
pressure, you can also try a small order!

https://www.aakindustry.com/info-det , ail/pressure-control-valves-aak458

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