AAK Hydraulic Cartridge Relief Valve Accuracy Process Skill

The original cartridge valve manufacturer could not improve the cone hole
roundness and surface roughness of the hydraulic cartridge relief valve. AAK
used 3 skills to ensure that the cone hole roundness of the hydraulic cartridge
relief valve was within 0.003, the surface roughness was Ra0.6, and it was
linear sealed, without leakage, helping Salim out of the after-sales trouble
that has stumped him for in 3 months.

Salim is from Chile. A batch of hydraulic cylinders of their company have been
complained by customers that they are unstable. After checking, it was found
that the hydraulic cartridge relief valve was leaking, which caused the
abnormal operation of the oil cylinder. The root cause was the roundness of the
cone hole and the surface roughness. The engineer requires to replace the
hydraulic cartridge relief valve, and the cone hole roundness is within 0.005,
and the surface roughness is below Ra0.8, which can completely solve the hidden
danger. The original manufacturer of the hydraulic cartridge relief valve said
that the new requirements is 50% higher than before, but he was willing to try.
He made samples twice, but still failed to meet the standard. 3 months passed
without any result. The customer was unhappy and Salim was worried.

Salim contacted me under the introduction of AAK's old customer Robert.
According to his introduction above, the parameter requirements alone are not a
big problem, but the internal structure of the original hydraulic cartridge
relief valve should be considered. Our engineer reviewed his drawings and the
anatomical drawing of the original hydraulic cartridge relief valve
manufacturer, and came up with the plan 2 days later. Salim asked AAK to make
samples. After 35 days, AAK sent 12 hydraulic cartridge relief valves. 3 weeks
later, Salim emailed that after replacing the hydraulic cartridge relief valve
of the original manufacturer, the hydraulic cylinder worked normally.

At the beginning of last month, Salim sent a PO for 240 hydraulic cartridge
relief valves. 8 months later, the customer no longer complained about the
hydraulic cylinder. His boss was very satisfied with the accuracy of AAK
hydraulic cartridge relief valves. The taper hole roundness was within 0.003,
the surface roughness was Ra0.6, and it was linear sealed and leak free. All
their hydraulic cylinders in stock should be replaced with AAK hydraulic
cartridge relief valves. AAK engineers improved the processing technology with
3 skills for the internal structure of the hydraulic cartridge relief valve:

1. The valve seat of the hydraulic cartridge relief valve shall be turned.
First, rough holes shall be drilled. The rotation speed of the drill is
1500~1800r/min, and the feed speed is 140~160mm/min. Then, the bottom hole of
the thread shall be machined at the bottom of the rough hole. In the middle
section of the rough hole, an enlarged hole shall be machined with a boring
cutter.

2. Finish the top of the rough hole with a milling cutter to form a tapered
hole, and then grind the enlarged hole with an internal and external grinder.

3. Use self-made grinding tools to grind and polish the top of the tapered hole
in 2 ways: low speed, fast feed, low speed and slow feed. The coaxiality
between the column bar in the middle of the tool and the top cone surface is
strictly controlled within the range of 0.003~0.005.

AAK hydraulic cartridge relief valve, there is unique skill to process, you can
also try a small order!

https://www.aakindustry.com/info-det , ail/cartridge-relief-valves-aak419

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