Hydraulic cylinders:Cylinder cushioning.

Cylinder cushioning

The end caps are generally made of cast iron or cast aluminum and incorporate threaded entries for ports. End caps have to withstand shock loads at the extreme ends of piston travel. These loads arise not only from fluid pressure, but also from the kinetic energy of the moving parts of the cylinder and load. These shock loads can be reduced with cushion valves built in the end caps.

The cylinder cushioning effect has been illustrated in Figure 5.7.

Hydraulic cylinders-0114

As shown in the figure, deceleration starts when the tapered plunger enters the opening in the cap resulting in a restriction in exhaust flow, from the barrel to the port. During the final small leg of the stroke, the oil must exhaust through an adjustable opening. The cushion design also incorporates a check valve in order to allow free flow to the piston during reversal in direction.

Consideration should be given to the maximum pressure developed by the cushions at the ends of the cylinder since any excessive pressure build-up would end up rupturing the cylinder.

Related posts:

System and process requirements:Process requirements
Compressed Air Transmission and Treatment:AIR DRYERS
Moisture and condensation:Humidity and Specific humidity
Introduction to pneumatic conveying and the guide:Definitions and Solids loading ratio
Design procedures:The use of equations in system design and Logic diagram for system design.
ROUBLESHOOTING PNEUMA TIC CIRCUITS:GLOSSARY
Introduction to hydraulics:Introduction and background
Pneumatic controllers.
Check valves:Pilot-operated check valves and Restriction check valves.
Pilot-operated valves.
Pump types:Gear pumps ,Vane pumps,Piston pumps and Combination pumps.
Hydraulic Pumps and Pressure Regulation:Pump types
BASICCONCEPTS OF THE RMODYNAMICS:PRESSURE
HEAT EXCHANGERS:ANALYSIS OF HEAT EXCHANGERS
NATURAL CONVECTION:EQUATION OF MOTION AND THE GRASHOF NUMBER

Leave a comment

Your email address will not be published. Required fields are marked *