The selection of sealing ring material is of great significance to its sealing performance and service life.According to the different materials and properties of the sealing ring, it can be roughly divided into the following categories:
1. High temperature resistant sealing ring;
2, high pressure sealing ring;
3. Corrosion resistant sealing ring;
4, wear resistant sealing ring.
1. V-type sealing ring
V-type sealing ring is an axial action of elastic rubber sealing ring, used as a rotating shaft non-pressure seal.The sealing lip has good activity and adaptability, can compensate for the larger tolerance and Angle deviation, can prevent the internal grease or oil leakage to the outside, can also prevent the invasion of splash water or dust outside.
2. U-ring
It is often used to manufacture reciprocating seals in hydraulic systems.It is widely used in the sealing of hydraulic cylinder in construction machinery.
3. O-type sealing ring
Mainly used for static sealing and reciprocating motion sealing.For rotary motion seals, only low-speed rotary seals.
4. Torque sealing ring
Generally installed in the outer circle or rectangular section of the inner circle in the groove for sealing.
5. Y type sealing ring
Widely used in reciprocating motion sealing device.
6, hole with YX type sealing ring
It is suitable for sealing the piston in the reciprocating hydraulic cylinder.
7. Retaining ring for YX type hole
It is suitable for use with YX type sealing ring when the working pressure of the cylinder is greater than 16MPa, or when the cylinder is eccentric, it can protect the sealing ring.
8. The shaft uses YX type sealing ring
It is suitable for sealing piston rod in reciprocating motion hydraulic cylinder.
9. YX type retaining ring (sealing ring) for shaft
It is suitable for use with YX type sealing ring when the working pressure of the cylinder is greater than 16MPa, or when the cylinder is eccentric, it can protect the sealing ring.
10. O-type rubber sealing ring
Applicable to hydraulic pneumatic system and various mechanical equipment and components, under the specified pressure, temperature and different liquid and gas medium, in the static or moving state sealing effect.
11. Retaining ring for O-ring (sealing ring)
It is suitable for use with O-ring when the cylinder pressure is greater than 10MPa.
12. J-type skeletonless dust ring (sealing ring)
Suitable for reciprocating cylinder, piston rod or valve stem exposed place to play a dust-proof role.
1, NBR nitrile rubber sealing ring
Suitable for petroleum hydraulic oil, glycol hydraulic oil, diester lubricating oil, gasoline, water, silicone grease, silicone oil and other media.Is currently the most widely used, the lowest cost of rubber seals.Not suitable for polar solvents such as ketones, ozone, nitro hydrocarbons, MEK, and chloroform.The general use temperature range is -40~120 ℃.
2, HNBR hydrogenated nitrile butadiene rubber sealing ring
It has excellent corrosion resistance, tear resistance and compression deformation resistance, ozone resistance, sunshine resistance and weather resistance.Better wear resistance than nitrile rubber.It is suitable for washing machinery, automobile engine system and refrigeration system using new environment-friendly refrigerant R134A.Not recommended for use in alcohol, ester, or aromatic solutions.The general use temperature range is -40~150 ℃.
3, SIL silicone rubber sealing ring
It has excellent heat resistance, cold resistance, ozone resistance and atmospheric aging resistance.It has good insulation properties.But the tensile strength of the sealing ring is worse than the general rubber and does not have oil resistance.Applicable to household appliances such as electric water heater, electric iron, microwave oven, etc.It is also applicable to all kinds of things that are in contact with the human body, such as water bottles, drinking fountains, etc.Not recommended for use in most concentrated solvents, oils, concentrated acids and sodium hydroxide.The general use temperature range is -55~250 ℃.
Viton fluorine rubber sealing ring
High temperature resistance is better than silicone rubber, has excellent weather resistance, ozone resistance and chemical resistance, cold resistance is bad.Resistant to most oils and solvents, especially acids, aliphatic hydrocarbons, aromatic hydrocarbons and animal and vegetable oils.Sealing requirements for diesel engines, fuel systems and chemical plants.It is not recommended to use on ketones, low molecular weight esters and mixtures containing nitrate.The general temperature range is -20~250 ℃.
5, FLS fluorosilicone rubber sealing ring
Its performance has the advantages of fluorine rubber and silicone rubber, oil resistance, solvent resistance, fuel oil and high and low temperature resistance are good.Resistant to attack by oxygen compounds, aromatic solvents and chlorine solvents.It is generally used in aviation, aerospace and military applications.Exposure to ketones and brake oils is not recommended.The general use temperature range is -50~200 ℃.
6. EPDM EPDM rubber sealing ring
It has good weather resistance, ozone resistance, water resistance and chemical resistance.Can be used for alcohols and ketones, also can be used for high temperature water vapor environment sealing.Suitable for bathroom equipment, car radiator and car brake system.Not recommended for food use or exposure to mineral oils.The general use temperature range is -55~150 ℃.
7, CR neoprene rubber sealing ring
Sunlight and weather resistance is especially good.Not afraid of dichlorodifluoromethane and ammonia and other refrigerants, resistance to dilute acid, silicone grease lubricating oil, but in the low point of aniline mineral oil expansion.It is easy to crystallize and harden at low temperature.Suitable for all kinds of atmospheres, sunlight, ozone and all kinds of fire resistant, chemical corrosion resistant sealed environment.Not recommended for use in strong acids, nitro hydrocarbons, esters, chloroform and ketones.The general use temperature range is -55~120 ℃.
8, IIR butyl rubber sealing ring
Especially good air tightness, heat resistance, sunlight resistance, ozone resistance, good insulation performance;It has good resistance to polar solvents such as alcohols, ketones, esters, etc. It can be exposed to animal and vegetable oils or oxides.Suitable for chemical or vacuum resistant equipment.It is not recommended to use with petroleum solvents, kerosene or aromatic hydrocarbons.The general use temperature range is -50~110 ℃.
9, ACM acrylic rubber sealing ring
Excellent resistance to oil, high temperature and weather resistance are good, but the mechanical strength, compression deformation rate and water resistance is slightly poor.It is generally used in automobile transmission system and power steering system.Not suitable for hot water, brake oil, phosphate ester.The general temperature range is -25~170 ℃.
10, NR natural rubber sealing ring
It has good wear resistance, elasticity, tensile strength and elongation.But in the air is easy to aging, hot sticky, easy to expand and dissolve in mineral oil or gasoline, alkali resistance but not strong acid resistance.It is suitable for automobile brake oil, ethanol and other liquids containing hydroxide ions.The general use temperature range is -20~100 ℃.
11, PU polyurethane rubber sealing ring
The mechanical properties of polyurethane rubber are very good, wear resistance and high pressure resistance are far superior to other rubber.Aging resistance, ozone resistance, oil resistance is also quite good, but high temperature hydrolysis.Generally used for high pressure resistance, wear resistance sealing links, such as hydraulic cylinder.The general use temperature range is -45~90 ℃.
12. Metal rubber sealing ring
Made of stainless steel wire, without any rubber composition, has a strong use characteristics.For example: in high vacuum, high and low temperature, strong radiation, and a variety of corrosion and other environments to maintain normal work.The sealing ring skin is made of different materials such as stainless steel, copper, PTFE and other materials according to different uses. The coated metal rubber component is used as the lining core, which has the advantages of high sealing strength, good effect and repeatable use.Sealing ring core is made of different diameter and density of metal wire, suitable for different pressure occasions.The general temperature range is -80~800℃.
1, can not be installed in the wrong direction and destroy the lip edge
A scar of more than 50μm on the lip may result in significant oil leakage.
2, prevent forced installation
Can not be hit with a hammer, but to use a special tool to press the sealing ring into the seat hole, and then use a simple cylinder to protect the lip through the spline parts.Before installation, smear some lubricating oil on the lips to facilitate installation and prevent burns during initial operation. Pay attention to cleanliness.
3, to prevent the extended use
The service life of the rubber seal of the dynamic seal is generally 3000~5000h, and the new sealing ring should be replaced in time.
4. The size of the replacement sealing ring should be consistent
The sealing ring of the same size should be selected in strict accordance with the instructions, otherwise the compaction degree and other requirements cannot be guaranteed.
5. Avoid using old sealing rings
When using a new sealing ring, it is also necessary to carefully check its surface quality to make sure that there are no holes, bulges, cracks and grooves and other defects and enough elasticity before use.