As we all know, materials, energy and information are the three cornerstones of modern industrial development. Its level of development represents the development capability of a country's overall science and technology. In materials science, bimetal technology is a very important means to increase the service life of mechanical parts. It uses ordinary metal materials as the mother body, while the working surface of mechanical parts is compounded with another layer of special alloy. In order to improve the wear resistance and corrosion resistance of the parts, the service life of the parts is increased. Taking the most economical material structure and achieving the highest economic benefits is the reason why bimetal technology has become a driving force for people in the material world.
In the field of plastic processing, with the rapid development of the plastics processing industry, various new types of modified plastic materials continue to emerge. In high-strength reinforced plastic materials, reinforcing fibers such as carbon, asbestos, glass, and boron are often added; in addition, in order to obtain various special properties, or to reduce production costs, plastic resins are often required to be added in a certain proportion. Various fillers, such as chalk, silica, recrystallized white, clay, cellulose, mica, talc, alumina and metal powder. The addition of these reinforcing agents, fillers and inorganic colorants, or the incorporation of sediment impurities into the machine during recycling of recycled plastics, has intensified the corrosion of the heart parts of the plastic extruders and plastic injection machines - the melter barrel and the conveying screw. Or wear failure, resulting in reduced production efficiency of processing machinery, unstable product quality, increased number of repairs and replacement parts, and increased costs, which have a great impact on the economic benefits of various plastic processing enterprises. The production situation is increasingly eagerly appealing to replace the conventional nitriding barrel screw with a highly wear-resistant, corrosion-resistant bimetallic barrel and screw as a heart part of the machine, extending the life of the machine.
So what is a bimetallic barrel? The surface of the inner hole of the barrel (or referred to as the sol cylinder) is composited with different kinds of high wear-resistant or highly corrosion-resistant alloy materials as a working layer. The alloy material generally has a thickness of 2.0 to 3.0 mm, a Rockwell hardness of 60 degrees or more, and a specially machined barrel, which is a bimetallic barrel; and a bimetallic screw is specified in its spiral edge. The working surface, or the entire spiral working face, is a special alloy with a thickness of 1.0 to 2.0 mm (the Rockwell hardness of the alloy is generally 58 degrees or more), which is specially machined. The unique advantage of bimetal barrel and bimetal screw is that it is less than 1 times higher than the price of ordinary nitriding cylinder screw, and the theoretical service life is 4 times or more than that of ordinary nitriding cylinder screw. .
In the plastic processing industry in the United States, more than 95% of extruders and more than 75% of injection machines use bimetallic barrels and bimetallic screws as the heart parts of the machine. Famous professional manufacturers have XALOY (Exasure) In Europe, 60% of all single-screw extruder manufacturers offer bimetallic products for selection, and 30% of manufacturers only offer bimetal products. Well-known professional manufacturers are: British BROOKES (Brooks) company, Germany KRAUSS-MAFFEI (Klaus Maffei company, KRUPP (Krupp) company. REIFENHAUSOR (Rifen Haoshe) company, Italy's OMG (Omag) company, Switzerland's BERNEX (Benets) company, etc. In Asia, the use rate of bimetal products is low, and a few rely on imports, except for Japan Steel Works, Japan Kobe Steel Works, Shanghai Rehabilitation Machinery Manufacturing Co., Ltd., Taiwan There are few other professional suppliers, such as Tianxing Company, which can develop and manufacture bimetal products on a full-time basis. The vast market demand and high-speed economic development have made the contradiction between supply and demand in the region increasingly intensified.
The α series alloy used for forming bimetallic barrels is the “X” series alloy optimized by XULOY Company of Shanghai Rehabilitation Machinery Manufacturing Co., Ltd., the “BERNEX” series alloy of Benetix Company of Switzerland, and the Hitachi Metals Co., Ltd. of Japan. The strength of the "H" series of alloys, research and development of a series of work surface hardened alloy materials suitable for low-cost production, high quality and durability. The alloy series is divided into three categories, six varieties: excellent wear resistance, low production cost and can completely replace the α101 series alloy of nitride products, which is suitable for adding reinforcing agent and filler in ordinary plastics; Excellent corrosion resistance, especially α201 series alloys resistant to various weak acids, suitable for the forming of corrosive plastics such as PTFE, PVC, PMMA, CP, PPS; and when the above corrosive plastics are in the forming process, When it is necessary to add reinforcing or filling components, it not only proposes corrosion resistance requirements for the machine, but also puts forward wear resistance requirements. At this time, the α301 series alloy is the best choice for the user.
With the vigorous development of the plastics processing industry in mainland China, various plastic manufacturers pay more and more attention to the inherent quality of the plastic products produced and the economic benefits of plastic production. On the other hand, the introduction of dozens of billions of plastic extruders and plastic injection machines in China in the early years, plus the same kind of machines produced by various plastic machinery companies in China in the early years, have gradually entered the renewal period, which is Formed another huge update market for plastic machines. In this process, bimetal technology has played an important role. The bi-metal cylinder is lined in the old barrel in a bushing manner, and a special wear-resistant alloy is added to the worn screw surface of the old screw. The barrel screw is refurbished with such bimetal technology. The material structure has become a bimetallic form, and the heart parts updated by this method are even longer than the new nitriding parts originally purchased. For large extrusion production lines, as well as large injection machines, the significance is not simply a question of the economic benefits of a factory, but even the overall situation of low-cost, high-speed development of the national economy.
In China's industrial sector, the economic losses caused by material failures are calculated at 100 million yuan per year. Time is not waiting for us. We expect bimetal technology to further develop rapidly in China's plastic processing industry in other industrial fields in China, and to usher in a more brilliant future in the process of industrial development in China.