There are many kinds of sealing rings. Below, Damenson Sealing will introduce to you how to choose O-rings.

        How to choose O-ring? Cylinder is a widely used actuator in pneumatic systems. According to different usage conditions, its structure and shape also come in many forms. Commonly used classification methods are as follows:

1. Select the O-ring according to the direction of the force exerted by the compressed air on the piston end face.

(1) Single-acting cylinder: The movement of the cylinder in only one direction is driven by air pressure, and the piston is reset by spring force or self-weight and other external forces.

(2) Double-acting cylinder: The reciprocating motion of the double-acting cylinder is entirely accomplished by compressed air.

2. Select O-rings according to the structural characteristics of the cylinder

(1) Piston cylinder O-ring

(2) Diaphragm cylinder O-ring

(3) Telescopic cylinder O-ring

3. Select the O-ring according to the installation form of the cylinder.

(1) Fixed cylinder: The cylinder is installed fixedly on the body, including ear seat type, flange type and flange type.

(2) Pivot-pin cylinder: The cylinder body can swing at a certain angle around a fixed axis.

(3) Rotary cylinder: The cylinder is fixed on the machine tool spindle and can rotate at high speed with the machine tool spindle. This kind of cylinder is often used in pneumatic chucks on machine tools to achieve automatic loading of workpieces (4) Embedded cylinder: the cylinder is built into the fixture body

4. Select O-ring according to the function of the cylinder

(1) Ordinary cylinders: including single-acting and double-acting cylinders, commonly used in situations without special requirements

(2) Buffer cylinder: One or both ends of the cylinder are equipped with buffer devices to prevent and reduce the impact on the cylinder head when the piston moves to the end point.

(3) Pneumatic-liquid damping cylinder: The air cylinder and the hydraulic cylinder are connected in series, which can control the movement speed of the cylinder piston and make its speed relatively stable.

(4) Swing cylinder: used in situations where the cylinder blade shaft is required to rotate around the axis within a certain angle, such as fixture rotation, valve opening and closing, etc.

(5) Impact cylinder: It is a high-energy cylinder that uses the high-speed movement of the piston rod to form impact force. It can be used for stamping, cutting, etc.

(6) Stepper cylinder: It is a cylinder that makes the piston rod extend to different corresponding positions according to different control signals.

Working characteristics of O-rings for imported cylinders: The working characteristics of the cylinder refer to the static and dynamic characteristics such as the output force of the cylinder, the change of pressure in the cylinder, and the movement speed of the cylinder. Because they have many influencing factors, many issues are still being studied. , so only a brief introduction is given here.

When using the special O-ring for imported cylinders, you must pay attention to its pressure characteristics, that is, the pressure changes in the cylinder. The cylinder is usually divided into an intake chamber and an exhaust chamber by a piston. When compressed air is input to the intake chamber, the exhaust chamber is in an exhaust state. When the force formed by the pressure difference between the two chambers just overcomes various resistance loads, the piston begins to move. When there is no load, the pressure required to start movement is only 0.02~0.05MPa. During the movement of the cylinder, the pressure in the intake chamber gradually increases to the air source, while the pressure in the exhaust chamber gradually decreases. The gas pressure in the intake and exhaust chambers changes with time, and its change curve is usually called the pressure characteristic curve of the cylinder.