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:

Benefits, drawbacks and operational issues:Tangible benefits to the user
System and process requirements:Process requirements
Compressed Air Transmission and Treatment:Hollow fibre filter
Air flow rate evaluation:Supply pressure and Volumetric flow rate.
Air movers: Types of air mover and Aerodynamic compressors.
Gas–solid separation devices:Separation requirements and Separation mechanisms.
High pressure:Single blow tank control
Erosive wear:Hardness measurement and Surface material.
Low pressure and vacuum:Pressure drop and Maintenance
Hydraulic accessories:Hydraulic accessories.
Control components in a hydraulic system:Manifolds
Control components in a hydraulic system:Sequencing valve.
Hydraulic pumps:Pump selection
Hydraulic Pumps and Pressure Regulation:Pump types
Hydraulic and Pneumatic Accessories:Hydraulic Piping, Hosing and connections.

Leave a comment

Your email address will not be published.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