Sheet machine extrusion

The plastic sheet produced by the extrusion method has good mechanical properties and optical properties, and has the characteristics of light volume, good light transmission, heat preservation, sound insulation, and convenient installation. It can be used as structural materials, packaging materials and thermoformed products. Raw materials are more and more widely used in architectural decoration, industrial manufacturing, agricultural production and other industries. Some plastic sheets can be used to produce industrial gaskets, electrical insulation materials, building materials, vehicles, or siding, partitions, floors and other products in ships; sheets are also raw materials for some thermoforming products, such as extruded sheets after Vacuum blister forming is used as refrigerator lining and door lining; sheet is the raw material for thermoforming packaging materials, and non-toxic transparent sheet is widely used in food packaging and medical packaging. PVC color board and transparent board are materials for advertising, modeling and making advertising light boxes, and PC sunshine board is a building decoration material with good weather resistance.

The width of extruded plates and sheets is generally 1-1.5 meters, and the maximum width can reach 3-4 meters. Conventionally, the thickness of 0.25-1mm is a sheet, and the thickness of 1mm or more is a plate. The raw materials of board and sheet are mainly thermoplastics, such as hard or soft PVC, PE, PP, ABS, PC, etc., and can also be filled, blended and modified, foamed materials, etc. In terms of types, it can be divided into single-layer or multi-layer composite boards, flat or corrugated, special-shaped cross-sections, and foamed boards and sheets.

Compared with other molding methods, the extrusion molding of board and sheet has the advantages of relatively simple equipment used in the production line, low input cost, and high production efficiency. The process flow of sheet extrusion molding is as follows: the molten plastic is plasticized and extruded by the extruder, and then enters the head through the grid plate. Now the flat head is widely used, which has a wide and thin outlet. From the barrel to the machine head, the flow channel changes from a circular shape to a slit shape (flat seam shape), and the material will be uniformly distributed along the width direction of the machine head, and the plate or sheet is extruded through the die, and the material flows through the entire mold flow channel The pressure is reduced to a moderate level, and the residence time is as short as possible, and no material stagnation occurs. Under the traction of the traction device, it is calendered by smooth rollers, then shaped by the trimming device, and finally cut into the required length by the cutting device.

In recent years, the progress of extrusion molding technology is concentrated in the increase of extrusion speed. High-speed extrusion has brought about a substantial increase in the production efficiency of sheet and sheet. High speed, high efficiency, and intelligence have always been the development direction of sheet extrusion equipment.

In terms of equipment innovation, in addition to increasing the screw diameter and aspect ratio, in order to increase production, measures such as increasing the installed torque, increasing the screw speed and increasing the specific drive energy have also been taken. At the same time, in order to improve the quality of products and the stability of production, various extruder manufacturers are also making technological innovations in the aspects of automatic control of extrusion production lines, online detection and precise synchronization of drive systems.

Nanjing Sumino Precision Machinery Co., Ltd. has a professional sheet production line. The company's main sheet manufacturing production lines include: PET/PRET sheet production line, PP sheet production line, PP vacuum profile extrusion line, PP/PC vacuum sheet production line, PC/PP corrugated board production line, PVDF photovoltaic backplane production line, PMMA acrylic sheet production line, PE waterproof membrane production line, high-performance barrier sheet production line, optical panel production line, multi-layer co-extrusion sheet production line, etc.