AAK Hydraulic Cartridge Valve Spring Service Life Control

A few days ago, Titan, an old customer from Türkiye, sent me 6 samples of
hydraulic cartridge valves. According to his description, there were 3
batches of the valves purchased from the original hydraulic cartridge valve
manufacturer, and 2 batches of valves had abnormal service life. Some
hydraulic cartridge valves had a service life of more than 1 million times,
while some hydraulic cartridge valves had only about 700,000 times. However,
no problem could be found in the selection of materials or accuracy of
hydraulic cartridge valves. The original manufacturer of the hydraulic
cartridge valves is also uncertain about the root cause of the problem,
which has made Titan very upset.

There are various possible reasons for unstable service life, such as
material selection, machining accuracy, internal structure of the valve, and
accessories. According to our testing, the valve provided by the original
hydraulic cartridge valve manufacturer is unstable due to the quality of the
spring, which affects the service life of the hydraulic cartridge valve.
Titan mentioned that the Korean piano steel wire material used by the
original hydraulic cartridge valve manufacturer should have a service life
of no less than 1 million times. Yes, it is the basic standard for high-
quality hydraulic cartridge valves to use piano steel wire. However, there
are details on where the spring is processed and how to test its service
life. Most hydraulic cartridge valve manufacturers just purchase springs
from processing plants and then assemble them directly. Once there is a
quality problem in the spring factory, it also affects the hydraulic
cartridge valve manufacturers.

Hydraulic cartridge valve manufacturer AAK controls the quality of springs
through material selection and testing, based on 3 details:

1.The selection of piano wire is inevitable.
2.The length of the spring must be measured using a caliper, with the unit
focused in millimeters.
3.The service life of the spring is controlled by specialized equipment.

As shown in the video, hydraulic cartridge valve manufacturer AAK requires
each batch of springs to undergo durability fatigue testing using a spring
life testing machine. After the spring is inserted into the fixture, select
the working mode in the program first, and then set 1 million tests to set
the amplitude and frequency of the spring. Adjust the distance between the
upper and lower pressure plates according to the length of the spring. After
starting the equipment, the reciprocating motion of the connecting rod
drives the compression work of the spring. The time and frequency of spring
operation can be tracked on the screen at any time. If the spring is less
than 1 million times, the program will automatically remind.

AAK hydraulic cartridge valve has a service life of over 1 million times,
which is the most basic requirement. You can also give it a try!

AAK HYDRAULIC CARTRIDGE VALVES (750) 2024-01-02

https://www.aakindustry.com/info , -detail/hydraulic-cartridge-valves-aak750

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