AAK solved the vibration problem of hydraulic counterbalance valve

Last October, Henry had planned to go to Hawaii with his family for a vacation.
The day before he left, he was informed that a customer complained about the
vibration problem of his company's hydraulic power unit during low-speed
operation. The boss asked Henry to solve the problem immediately. As the
purchasing manager of the company, he had to cancel the annual leave. The
engineer tested the hydraulic system on site and preliminarily judged that the
hydraulic counterbalance valve was abnormal. The engineer disassembled the
hydraulic counterbalance valve and failed to find out the reason. The hydraulic
counterbalance valve was tested separately, and each parameter was up to
standard. Henry began to contact the local hydraulic counterbalance valve
supplier and wanted to solve it as soon as possible, but there was no reply.

Henry found the original hydraulic counterbalance valve manufacturer. The
factory said that he OEM the hydraulic counterbalance valve completely
according to their hydraulic counterbalance valve drawings. He also specially
retested the hydraulic counterbalance valve in stock, and its parameter basis
was qualified. Henry was embarrassed to face such a situation. Henry thought of
AAK because we helped him solve the difficult problems of hydraulic
counterbalance valves several times before.

We received Henry's email and understood that neither the original manufacturer
nor the local manufacturer provided solutions. According to the working video
of the pressure unit provided by Henry, our engineers recognized their
preliminary judgment that the hydraulic counterbalance valve was abnormal. The
function of the hydraulic counterbalance valve is to balance the "negative load
force" opposite to the required movement direction, which makes the hydraulic
motor easier to control. The vibration problem in the complaint is that the
hydraulic counterbalance valve affects the control ability of the balance
circuit to the load. This is just our first surmise about the fault. The
specific situation needs to be determined in combination with the actual
hydraulic counterbalance valve samples.

Henry sent us the hydraulic counterbalance valve samples the next day. After
our engineers disassembled it, we are 90% confident that our judgment is
correct. The check valve throttling groove of their hydraulic counterbalance
valve is a traditional design. According to the working condition of their
pressure unit, the design of double triangular throttling groove of hydraulic
counterbalance valve has a little influence on the stability of valve spool.
The hydraulic counterbalance valves we shipped to a Russian customer 2 years
ago also encountered similar problems. I suggest Henry redesign the structure
of the hydraulic counterbalance valve. A month later, AAK sent out 10 samples
of hydraulic counterbalance valves, Henry installed the equipment for
commissioning, and there was no vibration problem.

AAK engineers changed the design of the check valve throttling groove of the
hydraulic counterbalance valve from double triangular throttling groove to
independent triangular throttling groove. The overflow area of the throttling
groove, the internal fluid flow of the check valve spool and the dynamic
characteristics of the balance circuit were compared and analyzed. Finally, it
was determined that the triangular throttling groove had a much smaller impact
on the stability of the valve spool and the system than the double triangular
throttling groove.

Henry sent me photos of a happy vacation in Hawaii and thanked AAK for solving
the problem professionally. His boss was very satisfied with his quick solution
to the problem and specially gave him two more days off. He was very happy.

AAK hydraulic counterbalance valves, your problem today may be the road I
walked yesterday. You can have a small try!

https://www.aakindustry.com/info-detai , l/hydraulic-counterbalance-valves-aak193

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