AAK solved the hole position drift of hydraulic valve blocks

Jone is a hydraulic customer from Canada. In recent years, his purchasing of
hydraulic valves has been very smooth. However, an urgent order of 200
hydraulic valve blocks in his hand recently gave him a headache. The customer
reported that 70% of the hydraulic valve blocks had large coaxiality deviation
between the hole and the outer circle, which damaged the thread of the
cartridge valve during assembly. The customer requested him to replenish half
of the hydraulic valve blocks within 15 days, but the original manufacturer of
the hydraulic valve blocks had to surrender. Although the lathe processing
parameters were adjusted, and even the hydraulic valve block materials were
changed, the hole position drift could not be solved, that is, the coaxiality
deviation between the hole and the outer circle was large. Jone consulted more
than 20 hydraulic valve block manufacturers before and after. Most of the
manufacturers said that they could not completely avoid the drift generated
during the drilling process of the hydraulic valve blocks, which could only be
controlled between 1-2‰, but the customer's requirements could not be higher
than 1‰. A week had passed, and Jone was still unable to give a plan for the
aftermath, and his boss was not satisfied.

Jone, introduced by his friend Blake, who is also my old customer, sent me an
email. According to his hydraulic valve block drawings and the layout of the
holes, I told him that during deep hole drilling, there would be symmetry
errors between the two cutting edges of the drill bit, or the sharpness of the
drill bit would be inconsistent after wear, which would cause the hole position
to drift. Under normal circumstances, for example, it is difficult to control
the 100mm drift value at 0.1mm, that is, the error of 1 ‰. There are really
not many hydraulic valve block manufacturers who can meet his customer’s
requirement standard. Even if the hole is reamed after drilling, the hole
position drift caused by drilling cannot be corrected. However, 3 years ago,
AAK did not adopt this traditional processing method and matured the new
processing technology. Jone asked me to help replenish the goods directly. The
customer had no time to wait for the samples.

Three weeks later, AAK sent a replenishment of 100 hydraulic valve blocks and
told Jone not to worry about the problem of hole drift that the original
manufacturer could not solve. AAK hydraulic valve block is processed by using
the outer circle to adapt to the inner hole, which is not only less than 1 ‰
of the error, but also has no deviation in the coaxiality between the hole and
the outer circle. Here is how our workshop processes it:

(1)Blanking, with a total length allowance of 2mm.
(2)Lathing the left end face to be shiny, rough lathing the outer circle to be
φ 35.5mm.
(3)Clamp the rough turned excircle at the left end and finish turning the right
end face to ensure a total length of 80 ± 0.05 mm. Drill and ream φ 4.9 ±
0.05 mm through hole.
(4)Deburr the holes at both ends, and process φ 4.9 ± 0.05 mm holes at the
two sharp tips, fine turning φ 34.9 mm outer circle.
(5)With φ 34.9 mm excircle as the benchmark to process other dimensions.

With φ 4.9 ± 0.05 mm holes machined first, and then φ 4.9 ± 0.05 mm hole is
used as the benchmark to process the remaining dimensions of the hydraulic
valve block so that the drift error in the processing of φ4.9 ± 0.05 mm hole
was corrected in the subsequent processing, and the coaxiality between the hole
and the outer circle of the hydraulic valve block was also guaranteed.

AAK hydraulic valve block valve hole, no hole drift, high coaxiality precision,
you can also have a small try!

https://www.aakindustry.com/info-detai , l/hydraulic-valve-blocks-aak268

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