Industrial seals can be divided into two categories: static seal between relatively static joint surface and dynamic seal between relatively moving joint surface.Static seal is mainly some sealing, glue seal and contact seal three categories.Dynamic seal can be divided into two basic types: rotary seal and reciprocating seal.According to the seal and its relatively moving parts contact, can be divided into contact seal and non-contact seal.Generally speaking, contact seal has good sealing, but limited by friction wear, suitable for sealing line speed is low.Non-contact seals have poor sealing and suitable for higher speeds.In the type selection, the basic requirements for sealing are good sealing, safety and reliability, long life, and should strive for compact structure, simple system, convenient manufacturing and maintenance, low cost.At the same time, most seals are vulnerable parts, should ensure interchangeability, to achieve standardization, serialization.The sealing material shall meet the requirements of the sealing function.Due to the different sealed media and the different working conditions of the equipment, the sealing material is required to have different adaptability.The requirements for sealing materials are generally:

1. Good material tightness, not easy to leak the medium;

2. Appropriate mechanical strength and hardness;

3. Good compressibility and resilience, and small permanent deformation;

4. Not softening, not decomposition at high temperature, not hardening or brittle cracking at low temperature;

5. Good corrosion resistance, can work in acid, alkali, oil and other media for a long time, its volume and hardness changes are small, and does not adhere to the metal surface;

6. Small coefficient of friction and good wear resistance;

7. Soft property combined with the sealing surface;

8. Good aging resistance and durability;

Convenient processing and manufacturing, cheap price, easy to use materials.

Common materials used for industrial sealing products are as follows:

1. Silicone

Silicone gel has outstanding high and low temperature resistance, ozone resistance and weather aging resistance, in the working temperature range of-70~260℃ can maintain its unique elasticity and ozone resistance, weather resistance, suitable for the sealing cushion required in the heat mechanism, such as strong light source lampshade sealing liner, valve pad, etc.Because silicone is not oil resistant, mechanical strength is low, expensive, so it is not suitable to make oil resistant sealing products.

2. Polyurethane glue

Polyurethane rubber has excellent rubber abrasion and good impermeability, using the general temperature range of-20~80℃.In addition, it also has medium oil resistance, oxygen resistance and ozone resistance to aging characteristics, but not acid and alkali resistance, water, steam and ketones.Suitable for manufacturing a variety of rubber sealing products, such as oil seal, O-ring and diaphragm, etc.

3. epoxy resin

Epoxy resin glue refers to a kind of epoxy resin liquid sealing material made with epoxy resin as the main composition, combined with all kinds of functional added materials and suitable curing agent.According to its different composition, it is mainly divided into single component epoxy glue and two component epoxy glue.

The main agent and curing agent of double component adhesive are separately divided and stored. AB mixing ratio before mixing can be carried out. For better quality, the colloid can be vacuumized and vacuolated before sealing.Due to their different curing agents, the two components are also divided into medium and high temperature curing type and normal temperature curing type, and there are also special and other curing modes.

Epoxy resin has superior performance and is widely used in electronic components such as electronic transformer, negative ion generator, module power supply, high pressure package, hydraulic water pump, relay, capacitor, ignition, coil, transformer, AC / DC module, LED, LED, L E D module, AC capacitor, (vertical, horizontal, box, film) capacitors, lighting, electrical appliances.