Hi, I recently came across this system, the pump having been replaced due to damage caused by cavitation (slippers/pistons destroyed) !!!!!
The pump being driven by a diesel engine (800 rpm idle speed and 2000 rpm maximum speed)
The system being an EATON 70423 RBT Pump (45cc displacement/210...
Hi, you don't mention the diameter of the cylinder (volume/area to work out pressure required to lift 2000KG) or whether double/single acting, but you'd probably get away with an accumulator large enough for the volume required for the speed, in the supply to system, prior to direction control...
Hi, Why don't you introduce a sequence valve into the supply to the brake release valve, set higher than system pressure required to the hydraulic motor to "hold" it on the slope when the brake is released. By installing it on the supply to the "Brake valve", when the valve is de-energised the...
Hi Rob,
Probably my mistake, but I assumed that the supply to both cylinders was common from a direction control valve and the cylinders were mechanically linked together (like the cylinders attached on either side of an excavator arm)thus requiring no flow divider!!!!!.
Regards,
JP
Hi, looking at your schematic, what is the purpose of the flow divider?, Why not just a"Tee".
Your schematic suggests a Counterbalance valve with an integral Relief valve (shock loading)on either side of cylinders for control in both directions.
The additional relief, downstream of flow divider...
Hi Kevin,
Is it possible that when the scissor lift is in the "low" position, and the additional weight when "loaded" has put the pivot points of the cylinders/linkage on the same axis, so that you have lost any mechanical advantage?. This could be tested by introducing a "Packer" for the...
Hi all, especially "oldhydroman",
Thinking about the options available I was considering one more, and "sounding you out" regarding it.
If the pump controller was replaced to make the pump a "pressure/flow compensated pump" with a "standby pressure" of 20/25 Bar. The "LS signal" to the pump...
Hi all, Please find attached schematic diagram. The system comprising of a 30Kw motor, a Bondioli & Pavesi HPA4 45cc axial piston "pressure control" pump (65 ltres/min)with compensator set at 175 Bar, an Integrated Hydraulics 7VR150 vented relief valve (set at 200 Bar) and a VRB 04 Flow control...
Hi all, Thanks for the replies - plenty of options to think about!!!!!.
Would it be practical to introduce a solenoid operated proportional contol valve to control a vent line signal connected to tank?
The existing Solenoid Operated Vented Relief valve is an "Integrated Hydraulics" 7VR150 valve.
Hi Ted,
My explanation of the system may not have been correct/clear initially.
The system has a pressure compensated pump set at 175 Bar, the problem being the "hydraulic hammer" created in the system when the solenoid operated vented relief valve set at 200 Bar energises or de-energises, with...
Hi, I am working on a system which comprises of a 65 litres/min Constant pressure axial piston pump (set at 175 Bar), together with a 110v AC Solenoid operated Vented Relief valve in the system set at 200 Bar, being utilised to discharge "walking trailers" via associated pipework, hoses and...
