Cylinder - working principle

Cylinder - Working Principle

The push and pull forces on the piston rod are determined based on the force required for work. Therefore, the cylinder should be selected so that the output force of the cylinder has a slight margin. If the bore diameter is selected to be small, the output force will be insufficient and the cylinder will not work properly;but if the bore diameter is too large, it will not only make the equipment bulky and costly, but also increase air consumption, resulting in a waste of energy. When designing the clamp, a force-increasing mechanism should be used as much as possible to reduce the size of the cylinder.

The following is the calculation formula for the theoretical output of the cylinder:

F: Theoretical output force of the cylinder (kgf)

F′: The output force when the efficiency is 85% (kgf)--(F′＝F×85%)

D: Cylinder bore (mm)

P: Working pressure (kgf/cm2)

Example: When the working pressure of a cylinder with a diameter of 340mm is 3kgf/cm2, what is its theoretical output force? What is its output force?

Connect P and D and find out the values ​​on F and F′ Point, get:

F=2800kgf;F′=2300kgf

When selecting the cylinder bore during engineering design, the cylinder bore can be selected based on its operating pressure and theoretical thrust or pulling force, and from the experience table Detected in 1-1.

Example: There is a cylinder whose operating pressure is 5kgf/cm2. When the cylinder is pushed out, its thrust is 132kgf (cylinder efficiency is 85%). Question: What cylinder diameter should be selected?

●Based on the cylinder thrust of 132kgf and the cylinder efficiency of 85%, the theoretical thrust of the cylinder can be calculated as F=F′/85%=155(kgf)

●Based on the operating pressure of 5kgf/cm2 and the cylinder According to the theoretical thrust, it is found that selecting a cylinder with a bore of 63 can meet the usage requirements.