I noticed that several of the aftermarket add-on steering valves (raven, trimble, etc) use counterbalance valves in their valve block designs. I have found a lot of information on counterbalance valves and their operation but it is always dealing with a lifted load. I am wondering what purpose they serve in a steering valve block. Only reason that I can think of is that the counterbalance valve is used to isolate the rest of the steering valve when turning the orbital with the steering wheel.
Have you a schematic as an exemple?
use brake valves to isolate and also to improve the precision of proportional valves. The force that acts on the tractor’s wheels from the field side is unpredictable in value and direction. The proportional valve precisely doses oil from the P side (pump), the T side opens wide. If force is applied to the wheels in the direction of valve opening, the wheels may move uncontrollably. To understand it better: it is impossible to use a cetop valve to raise and lower a weight in a controlled manner. You can raise it gently, but the lowering will be quick.
Braking valves maintain the descending pressure at a specified level.
I use braking valves in my auto-tuning systems, they work perfectly but they increase costs because they are expensive, and without them the quality of control is satisfactory. I would recommend them in small vehicles where low flows are required, then their effect is very visible. In large vehicles, they don’t make sense.
3 Likes
No schematic unfortunately. I was able to figure out what parts were in the valve block assemblies but don’t have any real reference for how they go together.
I didn’t relize that the return side basically free flows. I was thinking that flow in = flow out but that is not the case.