Application of bestov extrusion technology in auto

The application of belstov extrusion technology in the automotive industry

lightweight, comfortable and energy-saving are the latest trends in the development of the world's automotive industry, which has accelerated the process of automotive plasticization. At the same time, the plasticization of automobile also puts forward higher requirements for plastic materials, processing equipment and processing technology. In response to this latest change in the automotive market, belstov has developed a series of new extrusion technologies, which have been widely used in automotive manufacturing related industries

processing technology of modified materials

most automotive parts cannot be processed directly with basic resin, but need to be modified with basic resin. Commonly used modification processing means include: annual sales revenue of 5 alloying, such as pc/abs alloy; Reinforcement modification, such as blending PA or PBT with glass fiber; Filling modification, such as PP and CaCO3 or talc powder. The Ze basic series twin screw extruder of belstov company is developed to meet this kind of modified processing application

ze basic series includes various models of 25 ~ 77mm. Customers can choose different screw speeds of 600 ~ 1200r/min according to process requirements to achieve different production capacity requirements from 3kg/h to 2700kg/h. The biggest feature of Ze basic series twin screw extruder (as shown in Figure 1) is that on the premise of meeting the requirements of processing technology and efficiency, the equipment can be optimized to the greatest extent. By adopting the concept of standardized component design, the equipment can significantly reduce the cost and shorten the delivery cycle while maintaining advanced processing performance

for some materials, a high proportion of filling modification is usually required, and the proportion of filler is generally greater than 50%, and the filler itself is often a material with small particle size and low bulk density. In this regard, the free volume of the extruder has become a restrictive factor in the modification process. In order to solve this problem, belstov company launched Ze utx/ut-r twin-screw extrusion equipment, in which the screw groove depth ratio of R-type equipment is 1.74, which combines the comprehensive requirements of the equipment for torque and volume (as shown in Figure 2). When PP is filled and modified on Ze utx/ut-r equipment, the filling ratio can reach 80%

in addition, belstov's Ze utx-a twin-screw extruder can be used to process common automotive materials such as TPO or TPV. TPO does not need vulcanization, so the equipment is required to be short, and the length diameter ratio can be less than 30. Since TPV involves dynamic vulcanization, the aspect ratio of the equipment is generally required to be above 52

generally, three process points need to be overcome when processing TPV: the feeding of EPDM at this time, the elongation of the material is reduced to 5.8%, material distribution and dispersion, and dynamic vulcanization. In order to solve the cumbersome process problem of "EPDM rubber needs to be granulated before being fed into the twin-screw extruder", belstov developed a feeding system that can directly feed EPDM film or strip into the twin-screw extruder. This system composed of a single screw rubber extruder and a gear pump can convert rubber strips or films into melts, which are accurately measured by the gear pump and fed into the twin-screw extruder. At the same time, this device is also very helpful for optimizing the dispersion and distribution of materials (as shown in Figure 3)

in order to improve the distribution/dispersion and dynamic vulcanization, belstov developed a new type of shear tensile thread element, which can be used in conjunction with traditional conveying thread elements and kneading thread elements, and can achieve more perfect dispersion and more uniform vulcanization of rubber particles at lower melt temperature (as shown in Figure 4)

at present, some professional automotive engineering plastics modification plants have put forward higher requirements for cost and efficiency in production. In order to meet their requirements, belstov also launched a large capacity equipment - Ze ut twin-screw extruder. Among them, Ze 130 ut equipment can achieve 8t/h output by modifying PA + 30% - 40% glass fiber; For the modification of PP + 40% mineral filling, the output can reach 10t/h

processing technology of automotive interior skin

the most typical product of automotive interior skin is instrument panel skin (as shown in Figure 5), which is also the most demanding part of interior skin. The types of automobile instrument panel skin include pvc/abs calendered skin, TPO extruded skin and PVC plastic lined skin. The application of pvc/abs calendered skin is gradually decreasing due to its limitations in quality and environmental protection. PVC plastic lined skin is mainly used in high-end cars due to cost reasons. As a new material, the application of TPO extruded skin is receiving more and more attention

the production process of instrument panel skin includes extrusion, calendering, embossing, extinction, etc. in case of many abnormal conditions, the machine will be shut down immediately; Experimental report: (according to customer needs) links. The main machine of belstov's TPO automobile dashboard skin extrusion line generally adopts a twin-screw extruder. The excellent blending performance of this machine makes it possible for users to directly use PP and EPDM as raw materials without relying on TPO raw materials with high cost. At the same time, the twin-screw extruder is also conducive to evenly mixing various additives and resins to improve the performance of products

at present, the skin of some specifications of instrument panels is a two-layer structure, and the bottom material can be recycled to reduce costs. At this time, the extruder unit is a coextrusion unit composed of two twin-screw extruders. After the materials extruded by the twin-screw extruder pass through the exchanger and melt pump, they enter the flat die head, and then the flat die head feeds the materials to the three roller calendering roller frame. Due to the sensitivity of TPO material surface, the three roll calendering roller frame generally adopts the horizontal roller frame, in which the No. 2 roller can be used as a knurling roller to press the required pattern on the sheet surface (as shown in Figure 6)

generally, the sheets made need to undergo extinction treatment and increase the surface hardness of the sheets. All these are achieved by spraying appropriate solvents on the surface of the sheet. Only after these treatments can the sheet become the final product

belstov's TPO sheet extrusion line can also process pvc/abs formula products, enabling users to have a wider range of products. The capacity of a typical production line is 800 ~ 1200kg/h, the product width is 1500mm, and the thickness is 0.5 ~ 1.5mm

polypropylene foaming material processing technology

polypropylene foaming materials used in automobiles include polypropylene foaming sheets and molded parts made of polypropylene foaming beads

polypropylene foam sheet is mainly used as inner lining and sound insulation material of automobile ceiling and engine compartment, as well as spare wheel hatch cover, etc. The specification of the sheet is generally 1.5 ~ 6mm, the density is 60 ~ 150kg/m3, and the width of the product is 1000 ~ 1500mm

belstov's PP foaming sheet extrusion process is shown in Figure 7

in addition to polypropylene foamed sheets, another kind of PP foamed products are also used in cars, that is, components molded from PP foamed beads, including sun visors, headrests, hand pillows, door inner panels, bumper energy absorbing blocks, spare wheel seats, etc. Belstov's technology in this field is to process solid PP pellets into EPP foaming bead pellets with a density of 15 ~ 100kg/m3 by extrusion method. These pellets can be processed into various parts by steam molding equipment (as shown in Figure 8)

figure 8 PP foaming bead material

the process flow and equipment configuration of EPP foaming bead material extrusion equipment are shown in Figure 9, and the PP foaming bead material production equipment is shown in Figure 10

in the extrusion process of foaming beads, butane is used as the foaming agent, which can achieve a maximum foaming ratio of 60 times, and the particle diameter of the prepared beads is 3 ~ 5mm (as shown in Figure 11)

in the whole process of bead extrusion, the core of processing is extrusion and granulation. For extrusion, the temperature and pressure of the melt at the end of the extruder and the dispersion of the foaming agent are required to reach a very uniform and stable level, while the granulation process should take into account the mastery of the particle foaming process, the particle uniformity of the granulation and the mechanical matching accuracy of the granulation system

processing technology of automobile sealing strip

another kind of automobile related technology provided by belstov is the extrusion technology of automobile sealing strip - including the extrusion equipment of rubber sealing strip and TPV sealing strip

in the rubber sealing strip extrusion production line, in order to provide the downstream vulcanization line with high-quality rubber with uniform plasticization and no bubbles, the host machine can be equipped with a pin vacuum degassing extruder or a pin adjustable vacuum degassing extruder. For downstream vulcanization lines, belstov can provide microwave, hot air or salt bath vulcanization lines, which are suitable for the process requirements of different products

for the TPV sealing strip production line, in addition to processing traditional dense sealing strips, belstov also developed the foaming TPV sealing strip technology with water as foaming agent. Compared with chemical foaming technology, water foaming technology is more environmentally friendly

in practical application, TPV is often compounded with rubber to become the sealing strip of composite structure. In this regard, belstov has a special tpv/rubber composite coextrusion technology. This composite coextrusion die adopts the design of internal insulation, which can realize completely different melt temperature settings on the two adjacent channels to adapt to the different processing temperatures of rubber and TPV. (end)