Method of marking

O-ring specification representation method: Inner diameter * Wire diameter (ID*C/S)

Optional criteria: GB3452.1 series, AS568 series, JIS B 2401 series

★Note: Non-standard specifications can be customized

Different temperature ranges of synthetic rubber

Various synthetic rubber materials can meet the operating temperature of O-ring under different conditions. According to the working condition of the product, the O-ring rubber material suitable for its temperature can be selected.

Compression permanent deformation

Another index to evaluate the sealing performance of O-ring is the compression permanent deformation of the selected material. Under the action of pressure, as an elastic element of the O-ring, elastic deformation, as the pressure increases, there will be permanent plastic deformation. The compression permanent deformation d can be determined by the right equation:

Where: b0- original thickness (i.e. section diameter W) b1- thickness under compression b2- thickness after release

In general, to prevent permanent plastic deformation, the maximum compression allowed for O-rings is about 30% in static seals and 20% in dynamic seals.

Compression rate and filling rate setting

E (%)：Ratio of compression

T（mm）：Compression margin (T=W-H)

W (mm）：O-ring cut diameter

H（mm）：Depth of groove

n (%) ：Rate of filling

G (mm)：Width of groove

Compression ratio setting

Scope of use：8%-30%(dynamic seal: 8%-20%; Static seal: 15%-30%)

Setting of filling rate

Scope of use：max90%, design target value 75%

describe
The seal has a ragged edge, usually on the low pressure side.
Cause of
The gap is too large; Too much pressure; Material hardness or elasticity is too low; The groove space is too small; The clearance size is irregular; The grooves are too sharp; The seal is not the right size.
The Solution
Reduce the gap size, choose higher hardness or elasticity of materials, reasonable groove design.

describe
The seals show obvious crimp.
Cause of
Due to installation, the movement speed is too low, the material is too hard or too elastic, the surface treatment of the seals is not uniform, the groove size is not uniform, the groove surface is rough, and the lubrication is insufficient.
The Solution
Correct installation, choose high elastic type materials, choose self-lubricating materials, appropriate groove design and surface finish, try to use support rings.

describe
The contact surface of the seal presents planar permanent deformation.
Cause of
Too much pressure; High temperature; The material has not been cured; The permanent deformation rate of the material is too high; The material expands excessively in a chemical medium.
The Solution
Select materials with low deformation rate; Suitable groove design; Verify that the material is compatible with the medium

describe
Part or all of the seal presents a neat wound.
Cause of
Grooves and other parts edge and corner sharp, seal size is not suitable. The hardness or elasticity of the seal is too low; There is dirt on the surface of the seal.
The Solution
Clear sharp edges and corners; Groove design is more reasonable; Select the right size seal; Choose a seal with greater elasticity and hardness.

describe
The contact surface of the seal is deformed in plane and may be accompanied by cracks.
Cause of
Unreasonable design; The deformation of the material due to heat and chemical medium, or due to excessive pressure is not taken into account.
The Solution
The design of grooves should take into account the deformation of materials due to temperature and chemical media.

describe
The high temperature contact surface of the seals shows radial cracks, and some materials may become soft or shiny due to high temperature.
Cause of
The material cannot withstand high temperatures, or temperatures that exceed the expected temperature, or temperatures that change too quickly and too frequently.
The Solution
Choose materials with high temperature resistance, and reduce the sealing surface temperature as much as possible.

describe
The seal is faded, and a powdery substance remains on the surface. There are corrosion marks on the side without contact with the medium.
Cause of
Chemical reactions produce electrolysis, splash erosion (ions impact on the surface of the structure to cause material loss), scorching, groove design is not reasonable, sealing materials and media are incompatible.
The Solution
Select the appropriate material for the medium, lower the exposed area, and check the groove design.

describe
Wear occurs in all or part of the sealing area of the seal, and particles of worn material can be found on the sealing surface.
Cause of
The sealing surface is not smooth enough, the temperature is too high, the dirt with strong wear is infiltrated, the sealing parts have relative movement, and the sealing parts are not thoroughly treated on the surface.
The Solution
Use the recommended groove finish, use self-lubricating materials, and remove parts and environments that cause wear and tear.

describe
The surface of the seal presents bubbles, pits, scars; When the pressure is high, the material absorbs the gas in the medium. When the pressure is suddenly reduced, the gas absorbed by the material quickly escapes. Cause the sealing skin to burst.
Cause of
The pressure changes too fast and the hardness and elasticity of the material are too low.
The Solution
Choose materials with high hardness and high elasticity to reduce the speed of decompression.

describe
Chemical corrosion can cause various defects of seals, such as foaming, cracking, small holes or fading, and sometimes chemical corrosion can only be measured by instruments.
Cause of
The material does not conform to the medium or the temperature is too high.
The Solution
Choose materials that are more resistant to chemical media.

describe
This defect is often difficult to detect, and seals often appear as reduced section size.
Cause of
Improper curing of materials, high vacuum sealing requirements, low hardness of materials, or the use of materials with plasticizers.
The Solution
Avoid using materials with plasticizers and ensure that the seals are properly vulcanized to minimize leakage.

describe
There is a foreign body in the section of the seal.
Cause of
The production process is polluted by the environment, and the materials are corroded or reacted. The materials are non-semiconductor industry grade materials.
The Solution
Indicate the cleanliness of production and packaging requirements, strengthen the environmental control of the production, transportation and use of seals.