At present, the development of new products of sealing strips has changed the traditional design method. Instead, it uses computer technology, CAD/CAE/CAT, etc., to conduct high-starting analysis to achieve product structure optimization. Because of the complexity of the seal material, the particularity of the structure, the contact load and the nonlinearity of the boundary, the computer-aided design means can be used to improve the forecasting ability and reduce the cost of development and debugging.
The traditional design method is to determine the section, geometric shape and structural characteristics of the sealing strip through CAD drawing and modeling from the 3d data of the vehicle. Benchmarking technical benchmark files are used to select materials and their parameters. Through CAE analysis software, such as finite element FEM analysis, the deformation process is theoretically analyzed by simulating and analyzing the structure and deformation behavior of seal strips. If the design is unreasonable and the result is not satisfactory, CAD design can be adopted again. If it is successful, CAD tooling can be used for modeling design, and then CAM software, NC machine tool for processing. Then make the sample, after adjustment, finally complete the product development.
Some North American car seals manufacturers have broken through the traditional production of sealing strips. They are working with auto parts factories to provide some of the car factories with a composite frame with both guide grooves and sidebars, or entire doors. This approach is in line with the development trend of module supply in modern auto parts industry. In the raw materials used in the manufacturing of sealing strips, the main raw materials used in the past are also constantly updated and developed. It has excellent physical performance and novel EPDM with operable processing performance, which can control the long chain branching of its molecules, so as to improve its vulcanization performance and improve the extrusion speed and product yield. Other new types of thermoplastic elastomers such as EPO and TPV have been continuously developed and applied in automobile sealing strips. These materials have both good engineering properties of elastomers and excellent properties of plastics, making them controllable and recyclable. These materials are gradually replacing EPDM.
As for auxiliary materials, they are mainly carbon black, skeleton material, reinforcing agent, plasticizer and the vulcanizing agent, etc. They are also developing new products, which are applied in the production of automobile sealing strips
. At present, some computer application software has been developed to screen and combine the raw materials in the formula, so as to optimize the formula. Rubber additives are also developing towards high efficiency, energy saving, low pollution and low toxicity.