O-Ring Seal Groove Design Standard

1. It does not need to be so precise to deal with this kind of problem on site, the sealing effect of O-ring is still very good. For on-site treatment, there may not necessarily be spare parts of the appropriate size. If the outer diameter of the seal ring is larger or smaller, it is not a big problem. As long as it can be installed, it is better to be a little smaller; the cross-sectional diameter of the seal ring depends on the height of the step. , If the step depth is 2mm, the cross-sectional diameter of the seal ring is about 3mm, and the compression is about 1mm. As for the law, the outer diameter is better to be slightly smaller than or equal to the inner diameter of the step, and the amount of compression should not be too much. It must be ensured that the upper end of the step and the other end connected to it can be completely fitted under the normal tightening force.

2. The greater the pressure on the O-ring, the greater the deformation of the O-ring, the better the sealing effect of the O-ring will be obtained. When the pressure of the O-ring exceeds its bearing limit, the O-ring will be squeezed into the gap, causing the O-ring seal to fail. For this reason, when designing O-ring grooves, the relationship between O-ring hardness, working pressure and clearance tolerance must be reasonably matched.

3. First of all, it must be rod seal and static seal. The cross-sectional diameter of the o-ring seal is 3.55, which is the new standard. The specification is 3.55 and the inner diameter should be about 210. However, the national standard is only up to 2003.55, and there is no big one. It should be the wrong choice, re-select the standard of wire diameter 5.3. According to the outer diameter 210 and 5.3, the corresponding o-ring seal should be 2125.3, the static seal groove depth is t4.36, and the groove width d2 is 7.1. d1, that is, the diameter gap is determined by the working pressure and the hardness of the o-ring seal.

4. After the o-ring is installed in the groove, the o-ring must have a deformation amount to play a sealing role. When Hengchang is small, its deformation will be affected. For example, when the fixed groove type is used for sealing, the compression of the o-ring cannot meet the requirements and the end cover cannot be pressed in place. Because you didn't leave room for pre-compression. For example, if the grooves of reciprocating, spiral and rotating motion are small, because you did not leave room for the pre-compression amount, the pre-compression amount is too large during the movement. The first assembly is not easy to install, and the sealing ring is easy to cut. Second, it is easy to generate heat when it is in motion, which affects the service life of the sealing ring. So now that there is a national standard, it must be implemented in accordance with the standard. The formulation of each standard is based on the experience and lessons learned by relevant engineering and technical personnel from practice. All have his reason. Please forgive the wrong place.

5. The performance of different types of O-rings: Nitrile rubber: It is a representative material that is widely used. It has excellent oil resistance, abrasion resistance and stable heat resistance. It is resistant to fuel oils such as kerosene and light oil. Materials for general fuel oil. Silicone rubber: It is a material used in a wide range of synthetic rubbers with excellent heat resistance and cold resistance. It is a material with excellent heat resistance, water vapor resistance, and suitable for cylinder liners. Fluorine rubber: It is a material with excellent oil resistance, chemical resistance, heat resistance and a wide range of applications in synthetic rubber. Butyl rubber: Excellent chemical resistance and water resistance, but it is difficult to pass gas. Please do not use in mineral oil. Neoprene: a material with excellent weather resistance and Freon gas resistance. Polyurethane rubber: It has the characteristics of good mechanical strength, abrasion resistance and oil resistance, but it will age in chemically active oil with extreme pressure additives.