Hydraulic system factors affecting the performance of seals

Hydraulic oil for hydraulic drive system as the working medium , from the energy transfer , conversion and control role, while also playing the various components within the hydraulic system for lubrication , corrosion , rust and cooling effect.
Hydraulic system plays a seal to prevent leakage of fluid from the joint surfaces , maintaining the pressure , to maintain the role of energy transfer or conversion .
Sealing material used at home and abroad are mostly polymer elastomer , there are a number of special conditions, the use of plastic and various metals. But regardless of what kind of material , should have the following properties:
1 , with some mechanical and physical properties : such as tensile strength , elongation strength , elongation ;
2, there is a certain degree of flexibility, hardness fit and compression set ;
3 , the working media , not prone to swelling , decomposition , hardening ;
4 , wear, there are some anti -tear properties ;
5 , high temperature, low temperature aging .
However , there is no numbered seals sealing materials include all of the above properties , the need to work environment, such as temperature , pressure, media and sport mode to select the suitable sealing material , and through the development of materials with recipe to meet certain requirements . Or the use of composite materials or a combination of two or more structures in the form of play to their strengths, to achieve more comprehensive results.
Seal formation : dynamic seal is divided into non-contact seals and contact seals . Non-contact seal mainly a variety of mechanical seals , such as: graphite packing ring , floating ring seals ; rubber composite seals and rubber seals belong portfolio contact seals , relying on filling in a sealed chamber in the pre- compression force , leakage channel blocking sealing effect is obtained . Seals used in hydraulic systems are mostly static seal ( seal ) , reciprocating seals ( piston, piston rod plastic seals seal ) and rotating seal .
Factors affecting the sealing effect : seal structure selection and film formation , pressure, temperature , material compatibility , dynamic sealing contact with the working surface of the material, hardness , geometry, surface finish .