News

Application of high strength steel in bending machine When the high-strength steel is bent by the free bending method on the CNC bending machine, various defects are produced due to the sheet properties, equipment status, bending process parameters and other factors, which reduce the production efficiency and cause economic losses. In this paper, the main defect types of high strength steel under free bending are analyzed, and the corresponding improvement measures and countermeasures are put forward. Bending cracking When the R angle inside the bending is small to a certain value, the longitudinal material outside the plate may have cracks or microcracks at the R angle of the bending part due to excessive deformation, as shown in Figure 1. At the early stage of trial production of high-strength steel bending parts, bending cracking defects occurred frequently, which not only caused waste of plates, but also affected the normal progress of the project. The main factors causing cracking of high-strength steel bending parts are as follows. Bending radius The ultimate bending radius to prevent the outer fiber from cracking is called the minimum bending radius. The minimum bending radius is related to the mechanical properties of the material, the fiber direction of the sheet, the surface and side quality of the sheet, and the thickness of the sheet. Generally, with the increase of the material strength, the plasticity will decrease, and the minimum bending radius that the material can adopt will be larger. Bend line positioning method During the bending process, the bending line needs to be positioned to ensure the accuracy of the bending parts. The traditional manual line positioning methods mainly include manual or laser marking positioning method, process gap positioning method and machine tool stop positioning method. In the process of bending trial production of bp500 plate, when the process notch positioning method is adopted, the bending part cracks at the positioning notch. After notching the sheet metal, the original smooth edge shape changes sharply, and the stress at the notch is concentrated. When bending the sheet metal, the stress value of the material at the notch will first reach the strength limit, resulting in cracking. This also shows that bp500 plate has high requirements for material surface quality and side quality when bending process is adopted, and the surface shall be free of cracks, scratches, burrs, notches and other defects on the side. Therefore, the bp500 plate cannot be bent and positioned by the process notch positioning method, and the machine block positioning method without damage to the plate shall be preferred for bending. Bending springback When the bending part is taken out of the die, the bending angle and radius are inconsistent with the die, which is called bending springback. The main factors that affect the springback of bending parts are: mechanical properties of materials, relative bending radius r/t, bending mode, bending center angle and shape of bending parts. The springback angle is directly proportional to the yield strength and hardening index of the material, and inversely proportional to the elastic modulus. The yield strength of protective steel bp500 is not less than 1250MPa, so its rebound trend is much larger than that of ordinary plate. The bending angles at the left and right ends of the bending part are inconsistent During the bending process of bp500 material bending parts, it is found that some bending parts with long bending lines have inconsistent bending angles at the left and right ends. The causes of inconsistent bending angles at the left and right ends of the bending part are as follows: ⑴ the parallelism between the bending machine slider and the workbench plane exceeds the tolerance when it reaches the bending end position; (2) the parallelism between the installation surface of the upper formwork and the working bottom surface exceeds the tolerance; (3) the parallelism between the V-shaped groove of the bending lower die and the installation bottom surface exceeds the tolerance; (4) the thickness of the folded plate is inconsistent at the left and right ends. When the lower bending die is rotated by 180 °, that is, when the left and right ends are turned around for bending, the angle difference between the left and right ends of the bending part still exists, and the size values are exchanged left and right. It is speculated that the contact positions of the left and right ends are different when the upper bending die and the lower bending die are closed. After further investigation, it is found that the arc size of the working bottom surface of the bending upper die is inconsistent, which leads to the out of tolerance parallelism between the installation bottom surface of the bending upper die and the working bottom surface, resulting in the inconsistency between the left and right bending angles. By re machining the working bottom arc of the bending upper die, the flatness reached 0.05mm/m, and the problem of inconsistent bending angles at the left and right ends of the bending parts was solved. Concluding remarks To sum up, in the free bending of high-strength plates, the minimum bending radius and springback trend need to be tested first to ensure the consistency of bending machine accuracy, mold accuracy and sheet thickness, and then optimize and adjust the free bending process of the bending machine, such as the optimization of positioning mode, so as to effectively reduce the defects of high-strength plate bending parts and improve the product qualification rate.

There are many kinds of stainless steel, which can be divided into several types according to the organizational structure at room temperature: 1. austenite type: such as 304, 321, 316, 310, etc; 2. martensitic or ferritic type: such as 430, 420, 410, etc; According to the composition, it can be divided into CR system (400 Series), Cr Ni system (300 Series), Cr Mn Ni system (200 Series) and precipitation hardening system (600 Series). 200. series - chromium manganese nitrogen austenitic stainless steel 300. series - chromium nickel austenitic stainless steel 301 - good ductility, used for forming products. It can also be hardened rapidly by machining. Good weldability. The wear resistance and fatigue strength are better than 304 stainless steel. 302 - the corrosion resistance is the same as 304, and the strength is better due to the relatively high carbon content. 303 - it is easier to cut than 304 by adding a small amount of sulfur and phosphorus. 304 - 18/8 stainless steel. The GB brand is 0Cr18Ni9. 309 - better temperature resistance than 304. The second most widely used steel after 304 is mainly used in the food industry, pharmaceutical industry and surgical equipment. Adding molybdenum makes it obtain a special corrosion-resistant structure. Because it has better chloride corrosion resistance than 304, it is also used as "marine steel". SS316 is usually used for nuclear fuel recovery devices. Grade 18/10 stainless steel generally meets this application grade. [1] Model 321 - other properties are similar to 304 except that the risk of weld corrosion of the material is reduced due to the addition of titanium. 400. series - Ferritic and martensitic stainless steels. 408 - good heat resistance, weak corrosion resistance, 11% Cr, 8% Ni. 409 - the cheapest model (British and American), usually used as automobile exhaust pipe, is ferritic stainless steel (chromium steel). 410 - martensite (high strength chromium steel), with good wear resistance and poor corrosion resistance. 416 - the addition of sulfur improves the processability of the material. 420 - "cutting tool grade" martensitic steel, similar to the earliest stainless steel such as Brinell high chromium steel. It is also used for surgical knives, which can be made very bright. 430 - ferritic stainless steel, used for decoration, such as automobile accessories. Good formability, but poor temperature resistance and corrosion resistance. 440 - high strength cutting tool steel, with slightly higher carbon content, can obtain higher yield strength after proper heat treatment, and the hardness can reach 58hrc, which is one of the hardest stainless steels. The most common application example is "razor blade". There are three common models: 440A, 440b, 440C, and 440f (easy to process). 500. series - heat resistant chromium alloy steel. 600. series - Martensitic precipitation hardening stainless steel. 630 - the most commonly used precipitation hardening stainless steel model, usually also called 17-4; 17%cr, 4%ni. Popular articles What are the main functions of the bending machine? What are the safety technical measures and maintenance of the plate shears? Application of high strength steel in bending machine What are the types of stainless steel?

The plate bending machine is a shaping machine for continuous point bending of sheet metal. When the ordinary symmetrical three roll plate bending machine is used for plate bending, dead edges of a certain width will be left at both ends of the sheet metal. In this way, after being rolled into a cylinder, the pre bending function is to remove the dead edges and form a cylinder. There are many straight edges at both ends of the workpieces rolled out by the bending machine, which need to be welded and then rolled, which takes time and reduces the work efficiency. Main components of the bending machine: (1) Upper and lower rollers of the plate bending machine: it is an important part of the plate bending machine, and the material is forged carbon steel. (2) Plate bending machine frame: it is divided into left and right frames, each of which is equipped with a lower roll bearing. There is a square screw rod inside the frame, and the upper end of the screw rod is hinged with the bearing seats at both ends of the upper roll. Worm gear pair and screw pair are installed at the lower part. Rotate the nut in the worm gear to make the upper roll up or down. (3) Reducer: zsy280 hard tooth surface reducer is installed on the channel steel base together with the booster. (4) Unloading device of the plate bending machine: installed at the side of the reducer to balance the upper roll during unloading; Unloading and recovery are completed by the oil cylinder. (5) Base: welded by profile steel and steel plate. Install the frame, reducer, motor, etc. on it to form a whole. (6) Electrical part: all installed in a control box for easy operation. The electric control system of the bending machine consists of an electric control cabinet and an operation console. Power supply 380v/50hz. The main switch has the functions of short-circuit protection and overload protection of the main motor. The forward and reverse rotation of the motor is controlled by the AC contactor; The control circuit is controlled by relay, with reliable action and long service life. The console is equipped with product completion control button and indicator light to complete the operation and working state control of the whole machine. Rolling machine products are widely used in boiler, shipbuilding, petroleum, woodworking, metal structure and other machinery manufacturing industries. As a special machine, rolling machine plays an important role in industrial basic processing. All steel forming for cylindrical, almost all rolling machine roll system. It is applied in automobile, military industry and other fields. According to different requirements, it can roll steel columns that meet the requirements. It is a very practical instrument. Popular articles What are the main functions of the bending machine? What are the safety technical measures and maintenance of the plate shears? Application of high strength steel in bending machine What are the types of stainless steel?

The machinery manufacturing industry often needs to use CNC plate shears. What are the safety technical measures for CNC plate shears? In machining production, plate shears are widely used as a kind of shearing equipment, which can shear various thickness steel plate materials. The commonly used plate shears are divided into three types: flat shear, rolling shear and vibrating shear, of which the flat shear is the most used. Most plate shears with a shear thickness less than 10 mm are mechanically driven, and those with a shear thickness greater than 10 mm are hydraulically driven. It is generally operated by foot or button for single or continuous metal cutting. Wuxi Shenchong feels that attention should be paid to: 1. before work, carefully check whether all parts of the plate shears are normal, whether the electrical equipment is in good condition, whether the lubrication system is unblocked, and remove the sundries such as tools, measuring tools and corner wastes on the table and around. 2. it is not allowed to operate the plate shears by one person alone. Two to three people should coordinate the feeding, control the dimensional accuracy and reclaiming, and determine one person for unified command. 3. the shear clearance shall be adjusted according to the specified shear thickness. It is not allowed to cut two plates of different specifications and materials at the same time, and it is not allowed to cut by stacking. The sheared plate shall have a flat surface, and it is not allowed to shear narrow plates that cannot be compacted. 4. the belt, flywheel, gear, shaft and other moving parts of the plate shears must be equipped with protective covers. 5. the distance between the feeding finger of the plate shearer operator and the scissors mouth shall be at least 200 mm, and shall be away from the pressing device. The protective fence installed on the plate shears shall not prevent the operator from seeing the cut parts. The waste generated after operation has edges and corners. The operator shall remove them in time to prevent stabbing and cutting. Maintenance method of CNC plate shears: 1. Operate in strict accordance with the operating procedures. 2. Before each startup, add lubricating oil at fixed time, fixed point and fixed quantity according to the requirements of the lubrication chart. The oil shall be clean and free of sediment. 3. The machine tool must always be kept clean, and the unpainted part must be provided with anti rust grease. 4. The lubricating oil in the motor bearing shall be regularly replaced and filled, and the electrical part shall be regularly checked for normal, safe and reliable operation. 5. Regularly check whether the V-belt, handle, knob and key are damaged. If they are seriously worn, they should be replaced in time and reported to the spare parts for supplement. 6. Regularly check and repair the switch, fuse and handle to ensure their reliable operation. 7. Lubricate and scrub the machine tool 10 minutes before work every day. 8. It is strictly forbidden to operate the equipment by non designated personnel. Normally, people must leave the machine and stop. Popular articles What are the main functions of the bending machine? What are the safety technical measures and maintenance of the plate shears? Application of high strength steel in bending machine What are the types of stainless steel?

Five years of supply side reform giving birth to platinum in machine tool industry The essence of "supply side reform" is not to solve the oversupply we understand, but to solve the mismatch between supply and demand. After more than 30 years of rapid economic growth, many people have changed from low income and low consumption to medium and high income and medium and high consumption. According to the survey data of third-party institutions, China's middle and high-income people have exceeded 200 million. The general basic demand exists, but the change in income has also led to earth shaking changes in demand. People should not only consume, but also consume well. From having mobile phones to intelligent mobile phones; From TV to HD TV; From having air conditioners to pursuing low noise and energy-saving air conditioners; From ordinary train to bullet train; From driving to flying a private plane ----; The pursuit of better and higher consumer demand puts forward higher requirements for equipment manufacturing, and the higher requirements for equipment manufacturing are reflected in machine tools, that is, higher requirements for machine tools. Good products call for good equipment, and good equipment needs good machine tools. The core of supply side reform is to prepare for people's constant pursuit of better and higher demand. In recent years, a motorcycle parts enterprise in Chongqing has increased equipment investment, upgraded and transformed the existing equipment, introduced several medium and high-end CNC machine tools, and eliminated the original medium and low-end ordinary machine tools and low-end CNC machine tools. Enterprises carrying out equipment upgrading and transformation like this are not only in the motorcycle parts industry, but also in other industries, not only in Chongqing, but also in equipment manufacturing enterprises all over the country. However, not all equipment enterprises and industries are doing this. It is an equipment manufacturing enterprise that is market sensitive, pursues reform and can raise funds. It is they who have given birth to the recovery of the machine tool market and the coming five years of platinum in the machine tool industry. Upgrading of production to service industry mode For ordinary machine tools and low-end CNC machine tools, just recruit oneortwo people, and they can operate without looking at drawings, drawings or simple training. With the widespread use of medium and high-end CNC machine tools, once there is a problem, it can not be solved by ordinary workers or technicians. This requires that the machine tool industry not only provide better products, but also have good service, pre-sales, sales and after-sales service. Only good products and services can provide users with a better experience. An industrial model from product centered to user centered is emerging in the machine tool industry. It is not a simple slogan and a few systems that can determine the transformation from product centered to user centered. The first is an ideological revolution, from the top-level strategic design thinking to the grass-roots tactical implementation concept change; Secondly, it is a revolution of business process reengineering in the machine tool industry, from design to service, production to sales, so that customers can experience simple, intimate and different product design and service care; Then there is a management innovation in the machine tool industry, from product production and sales performance management as the center to customer satisfaction management as the core of comprehensive process reengineering and management. In the past, manufacturing enterprises were driven by production and sales, and transformed and upgraded to a new four-wheel drive driven by customer-centered customer service, product design, production quality and sales channels. The upgrading of industrial model is not only a crisis but also an opportunity, which can not be completed in a year or two. The resurgent machine tool market indicates that China's machine tools are ushering in five, eight or ten years of platinum. Internet + machine tool business model revolution Just think about it. Today you want to buy a pen for your child. You are willing to drive an hour to Jiefang, spend a long time finding a parking space, and then go to the stationery office on the third floor of the mall to buy a pen. Half a day has passed! Still willing to do it on the mobile phone or computer, waiting for the door-to-door delivery. If you are a purchasing supervisor or your boss wants to purchase a batch of computers, are you willing to take a car to the wholesale market, computer city, supplier companies, trade fairs, or just use your fingers on your mobile phone or computer? What is most closely related to us is the payment of telephone charges. Are you willing to look for business halls or recharge card stores all over the street, or recharge quickly on your mobile phone or computer in one minute? The real Internet is not only the display of information, but also the traditional thinking. The core of the real Internet tide is interactive communication and valuable sharing; Human nature is cheap, convenient, fast and inert. At present, there is no good business model of Internet + machine tools. On the one hand, the age of production and sales designers in the manufacturing industry is aging, delaying the widespread use of the Internet in the machine tool industry; On the other hand, the public network or display network lacks professional thinking and the solution of service problems in users' use. Internet + machine tool is a business model revolution. It eliminates all asymmetric information. It is a perfect combination of information and channels. Information and reputation reshape the traditional marketing concept. The Internet reshaping industry is first of all a subversion of brand machine tools: users no longer pay for brand premium, but only pay for product quality, service and technology. The innovation of business model in the machine tool industry is accelerating the arrival of five years of platinum in the machine tool industry.

With the popularity of the TV documentary "great country craftsman", the "great country craftsman" has become a well-known "hot word" to the public, and many well-known machine tool enterprises, such as CITIC Heavy Industry, Daguang evergreen, Baoji Machine tool, have emerged one after another. How to cultivate "big country craftsmen" in the machine tool industry? How can the public mention Chinese machine tool products in the same "awe" as Swiss watches and German machinery? Although the training of "big country craftsmen" involves many points and covers a wide range, it has still become a major focus of the development of the machine tool industry. It is urgent to forge the "craftsman spirit" and cultivate more "big country craftsmen" so that our manufacturing industry can win a place in the world. To improve the treatment of industrial workers and make them more respected and loved in the society, we need a fulcrum and platform, not just a paper article. The emergence of "chief worker" is an important fulcrum. "Chief worker" is a position specially set for key positions in the enterprise. The workers with this title are generally higher than other workers in the level of vocational skills, and have rich practical operation experience. Embedding the chief into the worker's identity is not only a concrete manifestation of respect for skills, but also an innovation in philosophy. At present, "made in China" is making great strides towards "made in China intelligently". The spirit of craftsmanship is particularly important for the machine tool industry, because mechanical equipment is made of hundreds of parts by hundreds of workers in nearly 100 enterprises. As long as one of the key processes goes wrong, the whole equipment will not work well. Indeed, according to the theory of "barrel benefit", the quality of a machine tool often depends on the key process of a part. However, the change of machine tool equipment made in China from "usable and unreliable" to "easy to use and very reliable" depends on the improvement of the whole industrial level. Quality and reliability come from design, manufacturing and management, but ultimately depend on the values, technical level and professional ability of designers, workers and managers, especially the technical level of workers' masters. The "king of knives", "king of welding" and "nizhifu drill" we are familiar with are all great craftsmen created in labor practice. Now, let's follow the steps of the small editor of China machine tool business network to enjoy the processing style of those "chief workers" in the machine tool industry and see how they inherit the "craftsman spirit". Dacheng craftsman xiehaibo: achieving zero medal breakthrough for China Xiehaibo: teacher of Foshan Nanhai technician college, member of the Communist Youth League, won the title of "2011 Foshan Nanhai District post technical expert pacesetter", "2013 Foshan outstanding contribution high skilled talent" and "2014 national technical expert". "The diameter of the thin-walled part of the test piece is 92.985mm, and the distance between the two faces is 20mm. This test piece is qualified." Recently, in the NC workshop of Nanhai technician college, which is nearly 10000 square meters, xiehaibo is guiding students in front of NC machine tools. Xiehaibo, 25, is a teacher of Nanhai technician college. Although he is young, he has attracted much attention because of his outstanding achievements in the field of technicians. Yaorusheng: from programmer to chief engineer to interpret craftsman spirit After graduating from technical secondary school in 1993, yaorusheng has been engaged in technical development and management in Guangdong Jirong Air Conditioning Co., Ltd. Asked if he would feel bored after years of working on the development and design of air-conditioning products, yaorusheng said firmly: "No. I am very interested in the development and design of air-conditioning products, and the company attaches great importance to technical talents. There are new projects to challenge from time to time, and I am willing to immerse myself in the process of continuous learning." From the programmer of the CNC machining center, to the product designer, the director of the equipment factory, the director of the design office, the director of the technology department, the director of the product business department, and then to the chief engineer of the company, yaorusheng summed up his career with "continuous learning": "what we are doing now is industrial air conditioners. The requirements of industrial air conditioners are different from other air conditioners. All air conditioners are non-standard and must be done according to the requirements of users." Yaorusheng told reporters that the design of each air conditioner is a process of learning new knowledge. In 2015, as the second accomplished person, Yao Rusheng participated in the scientific research project "key technology of air conditioning equipment for bimetal composite structure nuclear power plant" and won the third prize of Guangdong science and technology award. Great craftsman tanzhiqiang: the "helmsman" of heavy ware manufacturing Tanzhiqiang is the key equipment of CITIC Heavy Industries, the captain and monitor of the largest CNC gantry boring and milling machine in China, and the stationmaster of "tanzhiqiang great craftsman studio". After graduating from high school in 1986, tanzhiqiang started as an apprentice in boring and milling. His daily work is to process various parts on machine tools with boring and milling cutters. According to relevant standards, when the boring and milling workers operate the machine tool, the hole size error shall be controlled within 0.5mm, and the surface finish of the parts shall be polished to 6.5. Tanzhiqiang is not satisfied with this. Instead, he has set a more stringent standard for himself - the hole size error is controlled within 0.2mm, and the finish is aimed at a higher level of 3.2. In the past two years, tanzhiqiang and his big craftsman studio team took the initiative to undertake the company's major technical research projects and solve 19 key technical problems, creating a value of more than 12.8 million yuan for the company. Tanzhiqiang has been rated as "model Communist" by CITIC Heavy Industries for 7 consecutive years. On the eve of May Day this year, tanzhiqiang won the "National May Day Labor Medal". The times are progressing, and technology, equipment and talents are changing, but the spirit of craftsmanship remains the same. Being top-notch in the industry you are engaged in can not only promote your own development, but also promote the progress of the times. Many "chief workers" emerging in the machine tool industry are living beings, bringing fresh blood to "made in China 2025". The responsibility of the manufacturer is to take the eye that is good at discovering beauty, lead his own innovation subconscious to walk along the way, constantly stimulate the internal motivation, and discover the beautiful scenery on the road of technological growth from innovation. Labor is glorious, skills are precious, and creativity is great. I believe that with the joint efforts of the "chief workers", the machine tool industry will open a new page and express more brilliance.

In the past two years, China's machine tool industry has indeed encountered challenges, but challenges and opportunities coexist. For the development of China's machine tool industry, the Chinese government and machine tool enterprises have also made efforts for it. As the saying goes, "only by applying the right medicine can the disease be cured". So where is the way for China's machine tool industry, especially high-end CNC machine tools, to break through? Where is the way to break through? At present, the global machine tool industry is still at a low point, and there is no obvious sign of industry recovery; However, the domestic machine tool industry shows three characteristics: the industry is in the imitation stage, the key core technology is hollow, and it is deeply mired in the middle and low-end market. Industry insiders said that the three key paths for the breakthrough of the domestic machine tool industry are to reduce the production capacity at the middle and low end, replace imports at the high end and enter the machine tool consumption market. Among them, the promotion of medium and low-end capacity removal depends on the cooperation of enterprises, local governments and the state. The resistance in this process includes the interest game of local governments' taxes and so on; In addition, personnel placement after capacity removal, as well as capital and R & D investment in high-end capacity, are also difficult problems to be solved. The replacement of imported high-end CNC machine tools is the biggest goal and opportunity for domestic machine tools at this stage. At present, some domestic enterprises such as RIFA precision machine, Yawei Co., Ltd., Shenyang Machine Tool Co., Ltd. and Guangzhou CNC have certain accumulation of high-end CNC machine tool technology and production and processing technology. There is a gap between domestic and foreign enterprises in processing accuracy and product stability. If the industrialization of high-end CNC machine tools is solved, the gap between made in China and German industry 4.0 will be significantly narrowed. It is the third way for China's machine tool industry to break through from machine assembly to machine tool consumption. Despite the downturn in the machine tool market, the situation in the machine tool consumption market is quite good, and the performance of listed companies related to machine tool parts is also quite beautiful. A researcher from a securities firm said, "although the growth rate of the machine tool market is almost stagnant, the market for replacing key parts of machine tools is huge; in addition, the machine tool market after the transformation and upgrading of waste machine tools also has great potential." Future development is still expected Breaking through the shackles from the above three paths, together with the adjustment of economic structure and the deepening of government enterprise cooperation, the machine tool industry will develop rapidly. It is understood that due to the substantial growth in the demand of important equipment manufacturing industries such as national defense, aviation, high-speed rail, automobile and mold, China's CNC machine tool output has maintained a high-speed growth. The average annual compound growth rate of China's CNC machine tool output in the past five years was 37.39%. Combined with the total assets data of China's CNC machine tool industry and China's economic growth data in recent years, according to the linear regression prediction method, it is preliminarily estimated that the asset scale of China's CNC machine tool industry will reach 270billion yuan by 2020. In fact, the importance of machine tools and equipment has been fully reflected in the made in China 2025 and the technology roadmap. High grade CNC machine tools have been identified as one of the ten key breakthrough areas in the manufacturing power strategy, and breakthroughs in the other nine areas also depend on whether machine tools and equipment can take the lead in strengthening. Statistics show that the domestic market of high-end CNC machine tools has a scale of tens of billions of yuan and has good growth. However, this market is almost monopolized by foreign high-end CNC machine tools, and there is a huge space for import substitution. The development of China's CNC system industry has proved that the key core of high-end CNC systems cannot be bought back, and must be based on independent innovation. It is believed that after another 5-10 years of efforts, China's home appliances, mobile phones and other industries today may be a better tomorrow for China's high-end CNC machine tools and even the whole machine tool industry.