Classification of seals

The Sealing function in mechanical equipment is to prevent leakage. The parts that play a sealing role are called seals, which are called seals for short. Seal is one of the parts widely used in mechanical products. In the production, processing, storage, transportation and even sales of petroleum, petrochemical and chemical industries, there are often flammable, explosive, high temperature, high pressure, toxic and harmful, corrosion and other risk factors. The "dripping and leakage" of the working medium and lubricating oil of the machinery and equipment used has caused great harm to the production.

The leakage of working medium or lubricant in the equipment will cause waste and pollute the environment. Usually, substances leaked into the environment are difficult to recover, which seriously pollutes the air, water and soil. For example, many chemical plants have unpleasant smell and smoke, which cause serious pollution to the environment and seriously endanger the health of workers; The leakage of flammable, explosive, highly toxic, corrosive and radioactive substances may cause fire, explosion, poisoning and other accidents, leading to plant damage or even death, which may endanger the safety of personnel and equipment: gas, dust, water, etc. entering mechanical equipment in the environment will lead to premature wear and scrap of bearings, gears, etc. Mixing with chemical plant will affect the purity of chemical products; Internal leakage of fluid machinery will affect volumetric efficiency, etc. With the development of large-scale production equipment, the production process is developing towards high temperature, high pressure and high speed. There are more and more leakage opportunities, more and more serious accident risks, and more and more serious economic losses. Generally, leakage of pipeline or equipment may cause shutdown of a group of equipment or even the whole plant, and may also cause fire, explosion, casualties and other major accidents. Therefore, the sealing performance has become an important index to evaluate the quality of mechanical products.