AAK Hydraulic Cartridge Relief Valve High Back Pressure Circuit

Our old Greek customer, Evander, emailed me in November last year that he sent
me a sample of hydraulic cartridge relief valve, and stressing that it was not
his, but one of his partners, Ptolemy, and also attached Ptolemy's contact
information. After receiving the sample and communicating with Ptolemy, we
learned that the hydraulic cartridge relief valve was produced by a local
cartridge valve manufacturer in Greek and installed in their hydraulic
cylinder, which was unstable. Their engineers said that the root cause was the
high back pressure of the hydraulic system and the insensitive opening of the
hydraulic cartridge valve.

We can't determine the hidden dangers of the hydraulic cartridge valve just
according to the original sample. I suggested Evander sending us the video of
abnormal hydraulic cylinder, the drawing of hydraulic cartridge valve, and the
schematic of the system. After discussing, AAK engineers advised that the
problem can only be solved by reducing the opening back pressure resistance of
the hydraulic cartridge valve. Perhaps because of Evander's endorsement,
Ptolemy paid the development fee on the second day. I have always believed that
for industrial products such as hydraulic cartridge valves, it is difficult to
get the order without trust. With trust and reliable manufacturing quality, it
is easy to get the order. After 40 days, AAK sent 20 samples of hydraulic
cartridge valve.

Yesterday, Ptolemy emailed me that AAK hydraulic cartridge relief valve was
used on the hydraulic cylinder. The prototype operated stably and the hydraulic
cartridge valve opened sensitively. AAK hydraulic cartridge valve is stable and
sensitive under high back pressure. We optimized the structure of the original
hydraulic cartridge relief valve from 3 aspects.

1. The valve sleeve of the hydraulic cartridge relief valve has an oil inlet
cavity, and the outer circle of the valve sleeve is provided with a plurality
of annular through holes as oil outlet, and oblique holes are set to control
the oil outlet.

2. The middle part of the main valve spool is provided with a small hole
connecting the oil inlet cavity and the inclined hole, and the main valve spool
can slide in the valve body to form a spring cavity that is relatively closed
to the oil inlet cavity, and the spring cavity is equipped with a pressure
regulating spring.

3. The left end of the valve body is installed with an adjustable rod that can
be rotated and retracted and has a lock nut. The pressure regulating spring on
the adjusting rod is connected to the main valve spool. The outer diameter of
the right end of the valve body is provided with a sealing groove to place the
sealing ring group. Two sealing grooves are set on the left side of the
external thread of the valve body, and the sealing ring group is placed to seal
the connection with the socket to prevent oil leakage.

The optimized AAK hydraulic cartridge relief valve equalizes the pressure
difference on both sides of the valve spool through the small hole on the valve
spool, reducing the back pressure resistance of the hydraulic cartridge relief
valve opening. This makes it easy to open and enhances the sensitivity and
stability of the hydraulic cartridge relief valve.

AAK hydraulic cartridge relief valve, with high back pressure circuit, is also
sensitive and stable, you can also try it!

https://www.aakindustry.com/info-detail , /cartridge-relief-valves-aak504

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