Common classification of engineering machinery seals

Common classifications of engineering machinery seals include the following:

1. Oil seal (grease seal):

• Definition: Used to prevent leakage of lubricating oil, liquid or gas, usually used for sealing rotating shafts.

• Type: Lip oil seal, skeleton oil seal, combined oil seal.

• Material: Usually fluororubber, polyurethane or rubber composite materials are used to cope with different media and temperatures.

2. O-ring:

• Definition: A seal with a circular cross-section that can be used for static or dynamic sealing.

• Application: In hydraulic and pneumatic systems, it can withstand pressure and temperature changes.

• Material: Common materials include nitrile rubber, fluororubber and silicone rubber to meet different chemical and thermal environments.

3. Gasket:

• Definition: Used to fill the gap between two contact surfaces to prevent fluid leakage.

• Type: Non-metallic gaskets (such as rubber, foam, paper) and metal gaskets (such as copper, aluminum, steel).

• Application: Widely used in flange connections, pipes and equipment joints, especially in high temperature and high pressure environments.

4. Mechanical seal:

• Definition: Used in rotating equipment (such as pumps and compressors) to achieve sealing through static and rotating sealing surfaces.

• Structure: Usually composed of rotating rings, static rings, springs and sealing rings.

• Advantages: Provides excellent wear resistance, high temperature resistance and chemical corrosion resistance, reducing maintenance requirements.

5. Hydraulic seal:

• Definition: Designed specifically for hydraulic systems to prevent liquid leakage.

• Type: U-type seal, V-type seal, guide ring and end cover seal.

• Performance: With low friction, high wear resistance and strong pressure resistance, it is suitable for high pressure and high speed applications.

6. Pneumatic seal:

• Definition: Used in pneumatic systems to prevent compressed air or gas leakage.

• Type: Cylinder seal, guide ring and P-type seal.

• Material: Commonly used polyurethane, polytetrafluoroethylene (PTFE), etc., provide wear and pressure resistance.

7. Packing seal:

• Definition: Sealing rotating or moving parts through packing (such as graphite, polytetrafluoroethylene).

• Application: Suitable for high temperature, high pressure and corrosive environments, commonly found in pumps, valves and rotating equipment.

• Advantage: Has good adaptability and sealing performance, and can withstand certain wear.

8. Diaphragm seal:

• Definition: Use the deformation of elastic diaphragm to achieve sealing, suitable for isolating different media.

• Application: Commonly used in air pressure regulation, liquid containers and flow meters.

• Performance: Can provide high-precision sealing, corrosion resistance and temperature resistance.

The selection and design of these seals need to take into account factors such as the temperature, pressure, medium characteristics and movement form of the working environment to ensure the reliability and efficiency of engineering machinery. If you want to learn more about a certain type of seal or have specific technical questions, feel free to tell me!