Rubber O-ring conditions to meet the requirements

??Rubber O-rings are generally mounted on the outer or inner circular cross-section from the seal rectangular groove. Rubber O-ring still play a good sealing, damping effect in the oil, acid, wear, chemical attack and other environments. Therefore, the rubber O-ring hydraulic and pneumatic drive system is the most widely used a seal. Rubber O-ring seal should meet the basic performance of working conditions, workplace requirements, and indicate under pressure (pressure) and at a temperature range of a good seal.

??NBR (nitrile rubber) seals used in oil-based hydraulic oil, glycol-based hydraulic oil, gasoline, water, silicone grease, silicone and other media use. It is currently the most widely used and lowest cost rubber seal material. Not available in polar solvents such as ketones, smelly itchy, nitro hydrocarbons, MEK and chloroform. The normal operating temperature range of -40 ? ~ 120 ?.

??Flange cover such as rubber O-ring Axial clamping easier assembly and ensure the sealing performance. Rubber O-ring may be used as the low-speed rotational movement and a shorter operating cycle rotary shaft seal.

??When the peripheral speed is less than 0.5m / s, refrigerant resistance rubber O-ring selection according to the normal design criteria; when the circumferential speed is greater than 0.5m / s, will be considered after the shrinkage phenomenon stretched rubber ring is heated, so Select the ring inner diameter than the shaft diameter to be sealed it about 2% larger, the above phenomenon can be avoided. After the seal is installed in the groove, resulting ring being radially compressed refrigerant resistance rubber O-ring groove formed in micro corrugated canal, thereby improving the lubrication conditions.

??With a sealing system, the actual sealing rubber O-rings and seals at different effective length of time needed as much as possible identical or similar. Seals and seal wear, damage will affect the sealing effectiveness. To long life, the material of the sealing member should have a certain strength, stiffness, hardness, low coefficient of friction requirements, has good flexibility. Dynamic seal also has good lubrication conditions, the seal structure there should be reasonable geometry, and must not be defective.

??Xinhua Xu rubber O-ring quality should meet the requirements. That is, its dimensional accuracy, positional accuracy of the shape, surface roughness or passing good; its physical and chemical properties, such as elasticity, hardness (low hardness i.e. when its softness), mechanical strength, etc. in line with technical requirements residual deformation , the material structure is dense, nonporous, no pinholes, no bubbles, no wrinkles, no edges, no scratches and other surface defects.