Automated welding technology applications in the machine tool industry

  Foreword

    Mechanical machine tool industry is an important part of industry, mechanical industry, "general technology division," is the basic industry of national economy. Machine tools is to create all the machines of the machine, precision of their work is generally higher than the precision mechanical parts to be machined. To this end, the technological level of machine tool products and services for industrial products and economic efficiency of production technology plays a decisive role.

    As the machine tool products determines the specificity of the special structure of the machine. For decades, the cast structure has been dominated by the dominance of the machine structure. Casting has been the dominant technology for the machine tools. Eighties, with the introduction of machine tools increased technology, machine tool product mix more and more with a welded structure to weld on behalf of the cast, to weld on behalf of the forging, cutting to welding on behalf of the overall machine tool manufacturing industry has become trends. Welding process has also become an important basis for the machine tool manufacturing process and process technology from development into a single pre-processing, including raw materials, cutting off the material, forming welding, weld inspection and welding a new kind of post-processing integrated works technology. Completely changed the structure of casting the past few decades, "domination" of the situation, welding machine manufacturers have been inseparable.

    1 welding technology in machine tool industry

    Welding technology in the machine tool industry is a welded structure with the application of machine tools development to develop. China machine tool industry leading products are metal-cutting machine tools, forging machinery, foundry machinery, woodworking machine products, tool products, abrasive products and machine tool accessories. Among them, metal cutting machine tools, forging machinery and foundry machinery industry, welding machine products are the main areas of technology. From the development of machine tools technical level welding technology in the machine tool industry can be divided into three stages.

    1.1 welding technology as a supplementary means of stage craft

    This stage from the 1950s to the early 1970s. This stage in the development of machine tools machine tools abroad, mainly imitation stage. Metal cutting machine tools was the success of a 1Д63 generic type lathe, 2A125 vertical drilling, 6H82 Milling Machine, 1617 horizontal lathe horizontal boring machine and 262, 150 species, about the time to master the machine varieties for 70% of the total number of 204 kinds ; forging machine has developed a major generic open press, 315 ton closed single point press, air hammer, 300 tons double-disc friction presses, shearing machines, four-column universal hydraulic press and rolling machine and automatic forging machine demand for such a large general forging machinery.

    This stage the basic structure of machine tools for casting all the rough structure, so this phase of the welding process is only as a supplementary means for the products and services, the focus is cast welding defects in welding structural parts and products of the fuel tank, electric box cover Shell and some other small non-essential parts. The main method is manual arc welding, oxyacetylene welding, or, by the workers themselves, then no formal welding expertise and technological measures, no special welding shop. Individual large-scale enterprises, welding and foundry or other product assembly plant together, the production area is limited.

    1.2 Welding initial application stage

    This stage, from the 1970s to the early 1980s, for the welding of the initial application stage. This phase of machine tools in the 1950s on the basis of imitation, and began their own research and development of high-precision machine tools. In the metal cutting machine tools, only gradually to the 1970s provided a second car factory with a high level of 7664 machine tool, a second car plant was to meet the required 98% of machine tool equipment; in the forging machinery, for the second car plant and equipment, research and development of 510 units produced 115 kinds of forging machinery and general-specific part of the production line. At the same time, this stage of the professional point total plant species have mastered the forging machinery 257 species.

    At this stage, with the overall welding technology advances, some enterprises in the machine tool structure designed to start with a welded structure, such as Jinan Second Machine Tool Plant of 800 tons of mechanical press product base, beams and other large reservoir pump parts and components; Qiqihar Second Machine Tool Works, 1973 J81-1250 development and design of the trimming presses for the first time using a weldments, the main structural parts spare parts for the base, column and head, the maximum weight of 25 tons welding parts ; 1978 to 1979 the plant again in Z41-30-type nut cold heading machine bed, TA88-200 cold extrusion of a pressure vessel parts, using a welded structure. These welded structures used to promote the development of welding technology machine tool industry.

    From the late 1970s, companies began to establish qualified independent welding shop, a shop lifting equipment to increase and improve the welding tool. Machine Tool Plant, such as Jinan second welding workshop established in 1975, when the workshop area of ??5275 square meters, the maximum lifting capacity of 50 tons, welding tools from simple manual arc welding, submerged arc welding development, welding and electroslag ray detection materials and semi-automatic cutting off means testing. Machine tool industry to illustrate the application of welding technology, the start into a comprehensive engineering technology, machine tools for the third stage of introduction of technology laid the foundation.

    1.3 welding process stages leading

    The stage, from the early 1980s and since the introduction of technology. This stage, the machine tool industry by introducing foreign advanced design and manufacturing technology, to promote high-end products, the rapid development of advanced machine tools. Such as metal cutting machine tools, the Beijing First Machine Tool Plant and Japan's Hitachi Seiki co-production of K-type milling machine, and successfully developed a new series of CNC milling machine, while companies with German co-production of the Fort 瓦德里希柯CNC milling machine; Jinan First Machine Tool Plant and Japan co-production Iron Works Yamazaki Mazak lathe, Jinan Second Machine Tool Works in cooperation with the French BMO has developed a 4 × 10m large gantry beam mobile five-sided machining centers and large Φ200 CNC Floor Boring and 2.4 × 13m large gantry-style five-sided machining centers; Wuhan Heavy Machine Tool Plant and the Federal Republic of Germany Xishi. Florence Lipp companies to produce international standard machining diameter of 1.4 to 2.5 meter vertical lathe, boring bar diameter Φ260mm Boring floor above and other heavy machines. In the forging machinery, Jinan Second Machine Tool Plant of the U.S. VERSON first introduced the company's eight steel mechanical press series 35 varieties of heavy, super heavy-duty mechanical press design, manufacture, testing a full set of technology begins heavy, super- the introduction of heavy forging equipment, absorption, digestion stage. Subsequently, the 1981 Yellowstone Metalforming Machine Works has introduced hydraulic shears and bending machines Belgian series of drawings and manufacturing technology. Qiqihar Second Machine Tool Plant in 1986 introduced Japanese Komatsu Group's manufacturing mechanical press. In 1991, the Shanghai Metal Forming Machine Tool Factory and Germany SCHULER cooperation, the Shanghai Volkswagen plant to provide 14 sets of 600 t closed four-point multi-link mechanical press. 1992 Machine Tool Plant and Qiqihar second Al Swift cooperation with the German introduction of multi-link press manufacturing technology, and so on. Through the introduction, digestion and absorption, so that our heavy-duty, super-heavy forging equipment design capabilities, manufacturing level has been increasing rapidly, the basic approach and reached the international advanced level. Currently, the domestic forging industry has developed equipment for control of more than 440 kinds of forging, heavy-duty mechanical presses have been developed, stand-alone capacity of 3,000 tons, hydraulic bending machine, stand-alone capacity of 4,000 tons, and have the ability to develop stand-alone manufacturing 4500 tons or more super-heavy-duty mechanical presses and large multi-press capabilities.

    Introduction of technology for the machine tool industry, the application of welded structures. The second machine tool plant, such as Jinan, 1981 to design the mechanical press products, only 14% of the welded structure, planer welding structure product less than 1% in 1981, the introduction of press products, welded structure ratio of 44.3%. After the introduction of technology designed to self-digestion products of mechanical presses up to a welded structure, the proportion of 67.1%. The introduction of CNC machine tools of welded structures reached 60%. Forging Machine Factory, Tianjin, 1975, the welded structure using the number of product varieties only 8 species, less than 47%. 1991 exceeded 44 species, accounting for more than 66% of the total number of species.
wire cable tray, steel cable tray, outdoor cable tray
    The application of machine tools welded structure has changed in the past that rough casting machine structure dominate the world situation, welding machine tool industry has gradually developed into the leading process, which is mainly reflected in the following areas:

    (1) of the backbone enterprises of a certain size to establish a welding shop or metal structures plant and the establishment of a complete welding management system. Absorbing the introduction of the product welding standards, to implement the national professional standards, developed a corporate standard.

    (2) improve the welding process, so that from a single processing from raw materials into the development of pre-processing, cutting off the material, forming, welding, weld testing and treatment after welding a comprehensive set of new engineering technology.

    (3) computer programming CNC precision cutting and nesting technique has been applied, and changed the traditional hand-cut blanking, reduced machining to achieve the "cut-generation plane," "to weld on behalf of the cutting."

    (4) promote the use of CO2-rich gas and argon gas welding or submerged arc welding and other advanced, high-new technology. Welding work in the key enterprises exceeded 50%, 80% of individual enterprises.

    (5) commonly used by the X-ray inspection and ultrasonic nondestructive testing and other means, the inherent stability of the weld quality.

    (6) to promote the VSR new technology to achieve the reduction and residual stress in welded structures are of the purpose of reducing the deformation of welded parts, stable precision.

    (7) Welding and welders have been growing team, embarked on a standardized management, most of the enterprises of the welder certificates. In addition, "85" with industry representatives during the establishment of a meaningful point of welding plant model, the machine tool industry to promote the development of welding technology has played a catalytic role.

    (2) welding technology machine tool industry

    Machine tool industry, welding technology, with the imported product technology developed. Meanwhile, the domestic development of welding technology, welding technology for the machine tool industry applications. At present, the machine tool industry in the application of the main welding technology in the following areas:

    2.1 steel plate pretreatment technology

    Machine tool industry, steel plate pretreatment production line in 1993 by Jinan began to use the second machine tool plant, which is in the shipbuilding industry, heavy machinery industry, mining industry, based on the use began. The pre-plant and production line by the third Foundry Machinery Factory Qingdao joint development and manufacturing, the main process: steel leveling, warm, shot blasting, automatic painting, drying, length 60 meters. Main technical parameters: the thickness of steel leveling 8 ~ 40mm, the school-level width 3m; pre-plate thickness 8 ~ 160mm, the effective width of 3m; handle the maximum size of structural element 1500 (W) × 800 (H); pretreatment rate 0 ~ 4m/min; annual capacity of 40,000 tons / year; using PC automatic control and manual control in two ways. The steel plate pretreatment production line to solve the raw materials, corrosion, oxide and other adverse factors, improve quality and CNC cutting machine tools blanking the appearance of quality.

    2.2 CNC cutting technology

    The second in 1982 by Jinan CNC Machine Tool Plant began cutting machine-made parts used in cutting steel blanking among the 1988 application of computer technology, automatic programming nesting, utilization of the steel from 70% to 74%; 1992 Jinan First Machine Tool Plant in the United States introduced CNC plasma cutting machine and CNC laser cutting machine, CNC machine tool industry began, plasma and laser cutting applications, the thickness of 0.5 ~ 8mm of thin steel plate cutting accuracy of 0.5 ~ 1mm. "Plan" period, Jinan Second Machine Tool Plant research and development of thick steel plate CNC precision cutting technology, CNC precision cutting thick steel plate thickness of 275mm, the project won the Mechanical Department of the machine tool industry "Plan" process Achievement Award. In 1993, Jinan Second Machine Tool Plant of oxygen through the introduction of CNC underwater plasma cutting machine, the machine tool industry, CNC plasma steel cutting a thickness from 8mm to 25mm, reducing the cutting plate deformation, increase in cutting thick steel parts accuracy and cutting quality.

    2.3 high-efficiency gas-shielded welding welding technology

    With the introduction of foreign technology, the second in 1981 by Jinan First Machine Tool Plant applied Φ1.6 solid CO2 gas shielded welding technology to replace mechanical presses U.S. VERSON steel company Φ2.4 cored argon-rich gas welding process, welding welding of large-scale press process was research, and success. The project won the third prize of Ministry of Machinery technological advances. Machine Tool Plant in 1986, the second application of Qiqihar Φ1.2 solid argon-rich gas welding technology to solve large-scale welding parts welding press the issue, and copper-argon arc welding with a filament technology, piston, cylinder and so on the surface of copper layer of surfacing, alternative sets of our traditional copper succeed. Jinan First Machine Tool Plant in 1992, the sheet metal casing of the machine on the first application of the structural parts Φ0.8 solid CO2 gas shielded welding. "Plan" period, Jinan Second Machine Tool Plant CO2 gas welding also applied to the extended press tighten bolts welded on the project by Ministry of Machine tool industry "Plan" technology second prize. Currently, high-efficiency gas-shielded welding welding technology has been widely used in machine tool bed, gears, eccentric body, rocker shafts, cylinder block, not after welding pipe flanges and shell processing of such parts, machine tool industry has become One of the major welding processes.
keywords: