Stopping a Cylinder When Pressure is Lost

NL SONI said...
IT IS REQUIRED TO LOCK A VERTICAL SERVO HDRAULIC LINEAR ACTUATOR HANDLING A DEAD WEIGHT WHENEVER A LOSS OF PRESSURISED OIL SUPPLY TO THE ACUATOR. IT SHOULD INSTANTLY STOP AND GET LOCK AT THE SAME POSITION AT THE TIME OF OIL SUPPLY FAILURE.THE OPERATING PRESSURE IS ABOUT 20 BAR TO 100 BAR.KINDLY SUGGEST THE WORKABLE SOLUTION FOR THIS REQUIREMENTS.
August 18, 2009 9:26 PM

Suction Line Oil Level

I borrowed this topic from the H & P Forum but I have seen some discussion about my posts:

If positive displacement pump is running and stopped , pump is mounted on tank and suction length above oil level is 200 mm and there is no leakage in suction line and suction chamber ,whether the oil will remain full in suction line after pump stoppage . Will it fall down ?

What happens if length is 400 mm, 800 mm, etc.

Piston Seal Leakage - Rod Down

We have a cylinder mounted with the rod pointing down. It has a weight on the end of the rod.
There is a ball valve at each cylinder port.

Assumptions:

1. Piston seals are leaking badly
2. Rod seal does not leak
3. Ball valves, when closed, do not leak

What happens when the cylinder is fully retracted and both ball valves are closed?

Flow Control - Mislabeled???

How does a flow control control flow since all the oil in equals all the oil out?

Vertical Cylinder Question

Single Rod Cylinder - vertically mounted with rod up
10" Bore, 4" Rod, 10" stroke
Cap is vented to atmosphere and Rod end is plugged; assume no leakage.
Cylinder is about 3/4 extended.
What happens when a 500 lb load is applied to the rod?

Change in Load Question

The system consists of a fixed RPM electric motor, fixed displacement pump, system relief, cylinder, directional valve, and reservoir. If the cylinder is extending at a constant speed and the load opposing cylinder travel increases what happens to the speed of the cylinder?

General Comments about this Blog

Please provide your feedback and become a follower.

Thank you in advance.