Automotive sealing strip (Door, window, skylight)
Automobile sealing strip
Automotive sealing strip is one of the important parts, widely used in door, window, car body, skylight, engine case and reserve (luggage) box etc, with sound insulation, dust-proof, waterproof and damping function, keep and maintain the small environment inside the car, to play the car occupant, electrical and mechanical equipment and ancillary items of important protection. With the development of automobile industry, the importance of the beautiful, environmental protection and comfortable function of sealing strip is becoming increasingly prominent. The SEALING SYSTEM (automo-bile SEALING SYSTEM) installed in various parts of the automobile has been specially researched and developed in foreign automobile industry, and its importance is attracting increasing attention. 1. According to the name of the sealing parts (parts), the classification includes: engine HOOD seal, and can be divided into front, side and rear; DOOR SEAL; WINDOW screens for front and rear air Windows; SIDE window seal (SIDE Window seal); SUNROOF seal; PRIMARY DOOR SEAL; Sealing strip of window guide groove (GLASSRUN CHANNEL); Inner and outer strips (watercut)(WAISTLINE); TRUNK SEAL; Anti-noise sealing strip; Such as anti-dust. 2. According to SEALING characteristics, it can be classified into WEATHERSTRIP seal and general seal. Among them, the weather sealing strip is equipped with hollow sponge bubble tube, which has better temperature and humidity keeping function. Commonly used weather sealing strips include door frame sealing strip, suitcase sealing strip, engine case cover strip, etc. Commonly used general sealing strips are front and rear window sealing strips and corner window sealing strips, inner and outer strips, etc. 3. According to the compound structure classification of rubber material, it can be divided into pure rubber sealing strip -- composed of a single rubber; Two composite sealing strip -- composed of dense glue and foam foam glue, often in the dense glue in the direction of the axis containing metal skeleton material; Triple composite seal - consists of two types of sealant (one of which is light colored) and sponge sealant, usually containing a metal skeleton and reinforced fibers inside the sealant. Four composite sealing strip - Shanghai Shenya Sealing parts Co., Ltd. took the lead in the development and production of the composite sealing strip composed of 4 kinds of rubber materials, in the rubber (bubble tube) surface and covered with a thin layer of protective layer adhesive, so as to further improve the service life of seals. 4. According to the type of material classification, can be divided into rubber sealing strip; Plastic sealing strip; Thermoplastic elastomer seal strip. 5. Classified according to the surface treatment state, some sealing strip surface after additional treatment, can be divided into flocking sealing strip; Surface coating sealing strip; There are fabric seal strips. 6. Special function classification, some sealing strip has electronic intelligent function, such as anti-clamping sealing strip.
(2) material of sealing strip
Ethylene propylene diene diene (EPDM) is synthesized by polymerization of ethylene and propylene monomers with a small amount of non-conjugated diolefin. The structure of the polymer is characterized by unsaturated double bonds in the main chain and unsaturated double bonds in the branch chain. Therefore, it has excellent weather resistance, heat resistance, ozone resistance, uv resistance linear as well as good processing performance and low compression permanent deformation, so it is the preferred material for the production of sealing strips. At present, the majority of automotive sealing strip materials are using EPDM as the main raw material. According to the different parts and functions of the sealing strips, in practical application, vulcanization, protection, reinforcement, operating system materials and special given materials (such as colorant, foaming agent) are added to EPDM materials to form dense adhesive (including black adhesive and color adhesive) and sponge adhesive. Automotive sealing strip is mainly composed of good elasticity and resistance to compression deformation, aging resistance, ozone, chemical action, a wide range of temperature range (-40℃~+120℃) EPDM rubber foam and dense composite, containing a unique metal fixture and tongue buckle, durable, easy to install. It has long been matched with major automobile manufacturers.
Recommended temperature range:
EPDM Material -40 °F -248 °F (-40℃ -120 ℃)
Internal metal fixture material: steel wire or steel sheet
Natural rubber is a kind of polyisoprene as the main component of natural polymer compound, molecular formula is (C5H8) N, 91% ~ 94% of its components are rubber hydrocarbon (polyisoprene), the rest is protein, fatty acid, ash, sugar and other non-rubber substances. Natural rubber is the most widely used general purpose rubber. Because natural rubber has a series of physical and chemical characteristics, especially its excellent resilience, insulation, water isolation and plasticity and other characteristics, and, after appropriate treatment, also has oil resistance, acid resistance, alkali resistance, heat resistance, cold resistance, pressure resistance, wear resistance and other valuable properties, so, has a wide range of uses. For example, the daily use of rain shoes, warm water bags, elastic; Surgeon's gloves, blood transfusion tubes, condoms used in the medical and health sector; All kinds of tires used in transportation; Conveyor belts, transport belts, acid and alkali resistant gloves for industrial use; Agricultural use of drainage and irrigation hose, ammonia bags; Sounding balloons for meteorological surveys; Sealing and shockproof equipment for scientific experiments; Aircraft, tanks, artillery and gas masks used in defence; Even rockets, artificial earth satellites and spacecraft and other sophisticated scientific and technological products are inseparable from natural rubber. At present, there are more than 70,000 items in the world made partly or entirely of natural rubber. Thermoplastic Vulcanizate (Thermoplastic Vulcanizate), referred to as TPV
1, good elasticity and compression deformation resistance, environmental resistance, aging resistance is equivalent to epDM rubber, at the same time its oil resistance and solvent resistance and general neoprene similar. 2, wide range of application temperature (-60-150℃), wide range of soft and hard application (25A - 54D), the advantages of easy dyeing greatly improve the freedom of product design. 3, excellent processing performance: available injection, extrusion and other thermoplastic processing method processing, efficient, simple, no need to add equipment, high liquidity, small shrinkage rate. 4, green environmental protection, recyclable, and repeated use of six times without significant performance decline, in line with the EU environmental requirements. 5, the specific gravity is light (0.90 -- 0.97), the appearance quality is uniform, the surface grade is high, the feel is good. Based on the above performance characteristics, TPV is widely used in a wide range of applications with traditional rubber materials. At present, some products of automobile sealing strip are replaced by TPV of thermoplastic vulcanized rubber with EPDM. TPV of thermoplastic vulcanized rubber has certain alternative advantages in comprehensive performance and comprehensive cost.