Side effects of random increase in tonnage of metal baler

Material requirements for sealing rings of metal packers and hydraulic shears:

Because of the difference of sealing material's performance, the sealing performance of manufactured seals is also very different. Therefore, understanding the performance of sealing material is the precondition for correct design and selection of seals. When selecting sealing material, the following factors should be considered:

Permeability

Permeability also has an important influence on fluid seals. It should be paid more attention to gas seals, especially vacuum seals. The permeability of various rubber varies greatly.

The influence of friction on seal: friction is inevitable in dynamic seal. The magnitude of friction is related to material, fluid type, fluid pressure, working temperature, speed and surface roughness of seal. It directly affects the sealing performance and service life of seals.

Medium resistance

The swelling degree of the material in the medium is directly related to the sealing performance, so when selecting the material for hydraulic pneumatic seal, the first thing to consider is whether it can be compatible with the sealing medium.

Tensile strength

The tensile strength of sealing materials generally decreases with the increase of temperature. Therefore, the maximum service temperature and mechanical strength at high temperature must be considered. Low tensile strength is prone to stress relaxation and permanent deformation, resulting in seal failure.

Wear resistance

Wear resistance of materials is an important performance of dynamic seals. Good wear resistance leads to long service life. Wear resistance of materials

It is closely related to the hardness of the material. The higher the hardness of the material, the more wear-resistant it will be.

Permanent Deformation

Hydraulic pneumatic seals acquire sealing ability by generating recoverable compressive deformation in the sealing groove itself. Therefore, the permanent deformation of sealing materials should be small, elastic and resilient. In addition, the permanent deformation of materials is related to temperature. Low temperature and high temperature will increase the permanent deformation.

Elasticity

The extrusion seal relies on the springback force produced by the sealing material itself after being pressed to obtain the sealing ability. The lip seal may have eccentricity, and may rely on the elasticity of the material to compensate for the insufficient contact stress of the seal. Therefore, elasticity is very important for the sealing effect of the seal.

Hardness

Hardness is an important index of sealing material. It depends on the roughness of the sealing surface. The hardness of the rough sealing surface and the sealing parts should be low, so that the sealing effect is good. In the parts with high sealing pressure, the hardness of the sealing parts should be improved to prevent the sealing parts from over-deformation or even being extruded. In addition, the hardness of the materials can be used with time. The characteristics of temperature rise and decrease are high hardness and wear resistance of materials.

Temperature resistance

The working temperature of the seal depends on the temperature of the sealing medium and the temperature rise of the seal itself in the course of movement. Temperature directly affects the sealing performance. If the temperature is too high, the aging of the sealing material will be accelerated, resulting in a marked decrease in the elasticity and hardness of the material and a hardening of the material; if the temperature is too low, the material will harden and lose its elasticity. Therefore, metal packers should choose materials with a wide temperature range.