Raw materials in the sealing industry refer to materials that can withstand gap displacement to achieve airtightness and watertightness and are buried in building gaps, referred to as sealing materials. Sealing materials include metal materials (aluminum, lead, indium, stainless steel, etc.), non-metallic materials (rubber, plastic, ceramics, graphite, etc.) and composite materials (such as rubber-asbestos boards, etc.), but the most commonly used are rubber elastomer materials.
Sealing raw materials are divided into two categories according to their form: fluid sealing raw materials and non-fluid sealing raw materials.
Sealing raw materials should generally have good physical and mechanical properties, high resilience, small compression permanent deformation, reliable sealing, convenient processing, and long service life. Silicone rubber sealant is resistant to high and low temperatures, radiation, vacuum, pollution-free, and non-toxic; polysulfide rubber sealant has excellent resistance to aviation fuel, as well as resistance to high temperature, high pressure, friction, pressure, etc. These are the leading sealing material directions in the sealing industry. The quality of sealing materials directly affects the production efficiency of mechanical equipment and has a great impact on the efficiency of equipment use.
When used, the sealing raw materials can be formulated into liquid or paste, applied between the contact surfaces of two parts, cured under certain conditions or non-drying putty seal; they can also be processed into solid or hollow rings of various shapes and installed between the contact surfaces of two parts for sealing. The former is called sealing material, which is only used for static sealing parts where there is no relative movement between the contact surfaces of two parts; the latter is called sealing parts, which can be used for both static sealing parts and dynamic sealing parts where there is relative movement between the contact surfaces of two parts.
Sealing raw materials include metal materials (aluminum, lead, indium, stainless steel, etc.), non-metallic materials (rubber, plastic, ceramic, graphite, etc.) and composite materials (such as rubber-asbestos board, etc.), but the most commonly used is rubber elastomer material.
1. Molding method Most rubber seals use this molding method, such as various extrusion seals, rotating shaft lip seals, reciprocating lip seals, composite seals, film seals, bellows seals, etc.
2. Processing methods such as rectangular seals, piston ring seals, coaxial seals (or sliding ring combination seals), etc.
3. Plate or strip materials such as rubber, fiber-reinforced rubber, bonded asbestos fiber, aramid fiber, etc. Plate or strip materials are mostly used as sealing gaskets or fillers, and rubber is used as an adhesive for asbestos and its substitutes. Aramid fibers and processed rubber rings are sometimes used for reciprocating seals in aerospace equipment.
