Connection and sealing of cylinders

For stud and bolt connection, it is generally four bolts, but when the working pressure is higher than 1mp, it is necessary to check the bolt strength and increase the number of bolts if necessary.

The sealing quality of cylinder directly affects the performance and service life of cylinder. It is very important to design, select and use the sealing device correctly to ensure the normal operation of cylinder.

Requirements for sealing elements are as follows:

1) good sealing, wear resistance and long service life;

2) good stability, not easy to expand and contract, difficult to dissolve, not easy to age and soften;

3) low friction;

4) the seal surface shall be flat and smooth without bubble, impurity, bump and other defects. The surface roughness of the sealed element has an important influence on the service life of the sealed element. The surface roughness should be about RA = 0.4um.

5) simple structure and low cost.

Materials of sealing elements: oil resistant rubber, polyurethane, fabric rubber, PVC, grey cast iron or wear-resistant cast iron piston ring, chrome tanned cow leather, etc.

Shape of sealing element: O-ring, Y-ring, small Y-ring, L-ring, j-ring, U-ring and V-ring, metal piston ring, etc. The O-ring has the advantages of reliable operation, large static friction coefficient, simple piston structure, wide range of application at present, but its service life is slightly lower than other kinds. For dynamic seal, small Y-ring is widely used, its friction coefficient is smaller than other kinds, it has self compensation function after wear, and its service life is higher than others.