Hydraulic Cylinders Design
When hydraulic system must produce linear motion, cylinders (sometime called actuators or linear hydraulic motors) are the components what convert the fluid pressure and flow to straight-line, controllable mechanical force and motion to move load. The flow of the fluid into a cylinder causes the piston to move, and the fluid pressure gives the piston its mechanical force.
The high versatility of hydraulic cylinders allows designers to use actuators in various applications even in the most hoist environment, utilizing the size, configuration, design flexibility in combination with reliability and robustness.
CLASSIFICATION OF HYDRAULIC CYLINDERS BY CONFIGURATION
Double acting cylinders
These types of cylinders provide power in both directions, with a pressure port at either end.
Typical arrangements are
Single rod end
Double rod end
(nondifferential cylinders)
Positional or duplex cylinder
Tandem cylinder
Single acting cylinder
The single-acting cylinder is pressurized at one end only.
Typical arrangements are
Load return
Spring return
Ram (hydraulic press)
Telescopic
CLASSIFICATION OF HYDRAULIC CYLINDERS BY CONSTRUCTION
Tie-rod cylinders
Tie-rod cylinders use high-strength threaded steel tie rods on the outside of the cylinder housing for additional strength and stability.
Mill type cylinders
Mill type cylinders have flanges welded to both ends of their barrel with an end cap bolted to each flange (large mill-duty cylinders often have a barrel wall thick enough for the end-cap bolts to be threaded directly into the barrel wall)
Welded cylinders
Welded cylinders have a heavy-duty housing with a barrel welded directly to the end caps and require no tie rods.
