机械密封常识（Common sense of mechanical seal）.doc

机械密封常识（Common sense of mechanical seal） Seals can be divided into two categories: static seal and dynamic seal. Static seals are mainly gasket seal, sealant sealing and direct contact sealing three categories. According to the work pressure, static seal can be divided into medium and low pressure static seal and high pressure static seal. Low and medium pressure static seals are usually made of soft and wide width gasket. High pressure and static seals are made of hard material and metal gaskets with narrow width. Dynamic seals can be divided into rotary seal and reciprocating seal two basic types. According to the seal of the relative movement of the parts is divided into sealing contact, contact and non-contact seal; according to the seal and the contact position can be divided into circumferential seal and the seal, the seal is also called mechanical seal. The centrifugal seal and spiral seal in the dynamic seal are sealed by the power of the medium when the machine is running, so it is sometimes called the power seal. According to the type of sealing structure, sealing mechanism, seal shape and material, the classification of seal is: Static seal 1. pad seal (1) nonmetallic gasket (2) nonmetallic metal composite gasket (3) metal gasket; 2. glue seal 3. packing seal 4. bellows Two action seal 1. contact type dynamic seal (1) oil seal (2) expanding ring seal; (3) mechanical seal (4) hard packing seal (5) soft packing seal (6) forming seal (7) dustproof sealing; 2. non contact type dynamic seal (1) totally enclosed seal (2) magnetic liquid seal (3) floating ring seal; (4) labyrinth seal (5) screw seal; (6) centrifugal seal; 1 、 the working principle of mechanical seal Mechanical seal is by a number of or end of the vertical axis for relative sliding and compensation of fluid pressure in the elastic body (or magnetic) under the action of combined with auxiliary seal remain attached to the seal device leakage resistance. 2. Selection of common materials for mechanica