This control cylinder comes from a Komatsu open circuit pump (like this
one). In this generation the torque limiter control spool is placed
inside the servo-cylinder, along with the respective springs and what
not. The design solution is compact, but to make it work the
servo-piston has a thousand oil passages, which, aside from making it
resemble a chunk of swiss cheese, make it a weaker part, therefore
breakable at some point. This one snapped in the middle during normal
operation of the excavator...
Since this series is a rare client of our
shop, I am not sure whether this is a standalone case or a common
failure due to design flaw. If any of you ever saw something like this
- let me know, any feedback would be appreciated. In any case this
breakdown makes a nice series of kaboom pics.