awesome...last time I looked you could not find one for less than $800 and that was the low end...perfect for making a knuckle boom...that was my intention for a firewood processor...I'll give you $200 plus shipping/packaging costs...!
Could also be a drain line for letting fluid that bleeds through drain back to the fluid storage container.
Also could be for operating another device such as opening and closing a clam shell bucket or grapple.
I gave $800 for this one,
The 4 lines, two control the rotation and the other 2 control another function, such as the cyl for a grapple. The ports should be marked for each function.
Based on the data plate and a lot of Google-Fu, all I could come up with is that you have a Kinshofer KM235-20-3000 rotator - which I figure you already knew.
So the best advice I can give is to call/e-mail the US office and see if they can get you any documentation on it.
KINSHOFER USA
6420 Inducon Drive
Suite G
Sanborn, NY, 14132
Tel.: +1 (716) 731 4333
Toll Free (North America): 1 (800) 268 9525
Email: sales-usa@kinshofer.com