I have used a restricting ball valve on the output side of my last two setups without a problem. This merely replicates more head pressure on the pump and it will function fine like this.
In the past I have run into hydraulic applications that made me think about how this installation.
On the aircraft systems I have worked on, the flight controls are actuated by hydraulic pressure from a offset variable displacement piston/cylinder type pump. The offset creates the output variation and is controlled by a valve that maintains 3000 psi within the system. In short, if nothing is being moved, there is no demand and there is no output from the pump.
A simple hydraulic system, such as a log splitter, has a fixed output hydraulic pump that is pumping fluid the entire time. That pump has to have some kind of return so when the log splitter is not in the process of moving then there is a pressure relief value that dumps all the fluid back to the reservoir. If it did not, the pump would fail 100% of the time.
Both these systems are like our tanks in that our sumps are on all the time, however, most pumps we use can handle back pressure. If it can it is OK to add some type of restriction on the output of our returns. If they cannot handle back pressure, then you would need to plumb an overflow.
In the past I have run into hydraulic applications that made me think about how this installation.
On the aircraft systems I have worked on, the flight controls are actuated by hydraulic pressure from a offset variable displacement piston/cylinder type pump. The offset creates the output variation and is controlled by a valve that maintains 3000 psi within the system. In short, if nothing is being moved, there is no demand and there is no output from the pump.
A simple hydraulic system, such as a log splitter, has a fixed output hydraulic pump that is pumping fluid the entire time. That pump has to have some kind of return so when the log splitter is not in the process of moving then there is a pressure relief value that dumps all the fluid back to the reservoir. If it did not, the pump would fail 100% of the time.
Both these systems are like our tanks in that our sumps are on all the time, however, most pumps we use can handle back pressure. If it can it is OK to add some type of restriction on the output of our returns. If they cannot handle back pressure, then you would need to plumb an overflow.
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