Circuit problem
Circuit problem
(OP)
Please have a look at this circuit and see if you can give me some advice. The device labeled 2 is the one in question. This is a valve supplying fluid to 2 small cylinders. cylinders extend and allow fingers to locate on a machine tool holder. When valve is off cylinder retracts and locks onto tool. These cylinders are tiny and require 1/2 as much pressure as the other 3 devices on the circuit. Well when this circuit is working the cylinders on device 2 are extending and we have heavy tools falling on the ground. We think it might be related to a drain issue. Thanks in advance..John
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RE: Circuit problem
The two sandwich plates on #2 appear to be relief valves set to 425psi (425psi=30kg/cm2=3.0MPa), which dump to tank.
According to this schematic pressure from the P port can not be supplied to 2A and 2B at the same time.
Any back pressure in the tank line will reduce the holding force of the springs inside of the clamping actuators. I assume that there is some over-design, so lets assume that you only need 300-350 to extend the actuators. If you have 50psi of backpressure you have already lost ~15% of your clamping force.
Since you need hydraulic force to overcome the springs and extend the clamping actuators, the other explanation would be a sticking or miss-wired actuation valve.
ISZ
RE: Circuit problem
RE: Circuit problem
RE: Circuit problem
RE: Circuit problem
Or increase the return line size to reduce pressure required to return flow to the reservoir.
Ted
RE: Circuit problem
RE: Circuit problem
Ted
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ISZ
RE: Circuit problem
RE: Circuit problem
Probably fluid in the return line simply drained back out the cracked open fittings.
Ted
RE: Circuit problem
RE: Circuit problem
Ted
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RE: Circuit problem
Therefore, no hydraulic problem.
The springs are not applying enough force to hold the loads.
Ted