The status quo and development of stamping dies in China

In 1953, Changchun First Automobile Manufacturing Co., Ltd. established the first die shop in China. In 1958, the factory began to manufacture automotive cover molds. China began to produce fine-punching dies in the 1960s. After a long road of development, China has formed more than 30 billion yuan (excluding the statistics of Hong Kong, Macao and Taiwan, the same below.) The production capacity of various stamping dies.

First, the stamping die market situation

China's stamping dies have developed greatly in terms of quantity, quality, technology and capabilities. However, compared with the national economic needs and the world's advanced level, the gap is still large, some large, sophisticated, complex and long. The high-grade molds for life are still imported a lot every year, especially the cover molds for medium and high-end cars, which still rely mainly on imports. Some low-grade simple dies have become oversupplied and the market is fiercely competitive.

The current situation of China's stamping die market in 2004 is as follows:

According to the statistics released by China Die & Mould Industry Association, the total output of stamping dies in China was about 22 billion yuan in 2004, of which exports were 75 million US dollars, or about 620 million yuan.

According to China's customs statistics, in 2004, China imported a total of 561 million US dollars of stamping dies, about 4.66 billion yuan. From the above figures, it can be concluded that the total scale of China's stamping die market in 2004 was about 26.66 billion yuan. The total domestic market demand was 26.04 billion yuan, the total supply was about 21.38 billion yuan, and the market satisfaction rate was 82%. In the above overall situation of supply and demand, there are several specific circumstances that must be explained: First, most of the imported molds are large-scale precision molds with high technical content, while most of the export molds are medium and low-grade molds with low technical content, so the technical content is high. The mid-to-high-end mold market satisfaction rate is lower than the overall satisfaction rate of stamping molds. The development of these molds has lagged behind the production of stamping parts, while the low-grade mold market satisfaction rate is lower than the stamping mold market overall satisfaction rate; the second is due to China. The price of molds is much lower than that of the international market, and it has certain competitiveness. Therefore, its prospects in the international market are promising. In 2005, the export of stamping dies reached US$146 million, which is more than the increase of 94.7% in 2004. In recent years, Hong Kong-funded, Taiwanese-funded, and foreign-funded enterprises have developed rapidly in China. There are no definite statistics on the large number of self-produced stamping dies in these enterprises, so they cannot be included in the above figures.

Second, the level of stamping die

In recent years, the level of stamping dies in China has been greatly improved. Large stamping dies have been able to produce a single mold with a weight of more than 50 tons. Cover molds for mid-range cars can also be produced in China. Multi-station progressive die with an accuracy of 1~2μm and a life of 200 million times has been produced by many companies in China. The precision of the surface roughness reaches Ra≦1.5μm, and the large size (Φ≧300mm) fine die and medium plate precision die have reached a fairly high level in China.

1. Mold CAD/CAM technology status

The development of mold CAD/CAM technology in China has been more than 20 years old. The fine die CAD/CAM system jointly completed by the former Huazhong Institute of Technology and Wuhan 733 Factory was the first self-developed mold CAD/CAM system in China. The cold die CAD/CAM system jointly completed by Huazhong Institute of Technology and Beijing Mould Factory in 1986 is the first CAD/CAM system for blanking die developed by China. The cold die CAD/CAM system developed by Shanghai Jiaotong University was also completed in the same year. Since the 1990s, CAD/CAM technology has been adopted in the design and manufacture of molds for the domestic automotive industry. The National Science and Technology Commission 863 Program will use Dongfeng Motor Corporation as a CIMS application demonstration plant. The CAD/CAPP/CAM integrated system for automobile body and cover parts developed by Huazhong University of Science and Technology as a technical support unit was approved in early 1996. During this period, FAW and Chengfei Auto Mould Center introduced workstations and CAD/CAM software systems, and applied them in mold design and manufacturing, and achieved significant benefits. In 1997, FAW introduced the computer simulation CAE software for sheet metal forming process and began to use it for production.

In the 21st century, CAD/CAM technology has gradually become popular, and now there are CAD/CAM technologies for stamping die enterprises with a certain production capacity. Some key key enterprises also have the CAE capabilities.

Mold CAD/CAM technology has significantly shortened the mold design and manufacturing cycle, reduced production costs and improved product quality, which has become the consensus of people. During the "Eighth Five-Year Plan" and "Ninth Five-Year Plan" period, a large number of mold enterprises have popularized computer graphics technology, and the use rate of CNC machining has become higher and higher, and a considerable number of CAD/CAM systems have been introduced. For example, UG of US EDS, Pro/Engineer of Parametric Technology of the United States, CADS5 of CV of the United States, DOCT5 of DELCAM of the United Kingdom, CRADE and space-E of HZS of Japan, and Cimatron of Israel, also introduced software such as AutoCAD and CATIA. And special software such as Euclid-IS for automotive and cover moulds from Marta-Daravision, France. Domestic automotive panel mold manufacturers generally adopt CAD/CAM technology. Both the design of the DL diagram and the design of the mold structure diagram have realized two-dimensional CAD. Most enterprises have already made a transition to three-dimensional, and the production of the total map gradually replaces the production of the parts map. And the parametric design of the mold has also begun to go to the field of technology development of a few mold manufacturers.

In terms of stamping and forming CAE software, in addition to the introduced software, Huazhong University of Science and Technology, Jilin University, Hunan University, etc. have developed a high level of software with independent intellectual property rights, and have been successfully applied in production practice, resulting in Good results.

Rapid prototyping (RP) combined with traditional fast economic molds, rapid manufacturing of large automotive cover molds, solving the original low melting point alloy mold casting mold by sample, low mold precision, low precision of parts, difficult to make prototypes, etc. It realizes the rapid mold manufacturing based on the 3D CAD model as the basis for the mold making, and guarantees the precision of the parts. It provides the guarantee for the manufacture of the new model of the automobile industry and the rapid trial production of the body. It marks the application of RPM to the automobile. The prototype of the large body cover has been successful.

Around the rapid prototyping of automobile body and the rapid manufacture of large-size cover molds, some new rapid prototyping methods have emerged in recent years, such as moldless multi-point molding and laser shock and electromagnetic forming technologies that have been applied in production. They all show the advantages of reducing costs and improving efficiency.

2. Mold design and manufacturing capabilities

Under the correct guidance of the national industrial policy, after decades of efforts, the design and manufacturing capabilities of stamping dies in China have reached a high level, and many modern design and manufacturing technologies, including information engineering and virtual technology, have been applied in many mold enterprises.

Nevertheless, China's stamping die design and manufacturing capacity is still far from the market demand and international advanced level. These are mainly in the high-end car and large and medium-sized car cover molds and high-precision die, regardless of design, processing technology and capabilities, there is a big gap. The car cover mould has the characteristics of design and manufacture difficulty, high quality and precision requirements, and can represent the level of the cover mould. Although it has basically reached the international level in the design and manufacturing methods and means, the function of the mold structure is also close to the international level. It has made a big step in the process of localization of car molds, but in terms of manufacturing quality, precision, manufacturing cycle, etc. There is still a certain gap compared with foreign countries.

The multi-station progressive die and multi-function die with advanced mark die technology are the key molds developed in China. Representatively, it is a multi-functional mold that integrates mechatronics and iron core precision automatic valve, which has basically reached the international level.

However, compared with the foreign multi-station progressive die, there is still a certain gap in manufacturing precision, service life, mold structure and function.

The automobile cover mold manufacturing technology is constantly improving and perfecting, and the use of high-precision and high-efficiency processing equipment is more and more extensive. There are more and more applications for high-performance five-axis high-speed milling machines and three-axis high-speed milling machines. The application of NC and DNC technology is more and more mature, and it can carry out the inclination processing and super finishing. These all improve the precision of the mold profile, improve the quality of the mold, and shorten the manufacturing cycle of the mold.

Mold surface strengthening technology is also widely used. Ion nitriding technology with mature technology, no pollution and moderate cost is more and more recognized. The application of carbide coating (TD treatment) and many plating (coating) layers on stamping dies is increasing. Vacuum processing technology, solid casting technology, and edge surfacing technology are becoming more and more mature. Laser cutting and laser welding techniques have also been applied.

3. Degree of specialization and distribution

The degree of specialization in China's mold industry is still relatively low, and the proportion of self-produced molds is too high. The ratio of self-production and self-production of foreign molds is generally 30%, and the proportion of self-produced stamping molds in China is 60%. This has had a lot of adverse effects on specialization. Nowadays, molds with high technical requirements and large input have higher specialization, such as cover molds, multi-position progressive molds and fine punches. The general degree of specialization of the die is lower. Due to the high proportion of self-matching, the distribution of stamping die production capacity basically follows the distribution of stamping parts production capacity. However, the distribution of professionally-producing automotive cover moulds and multi-station, multi-functional precision stampings is not distributed with the distribution of stamping capabilities, but often depends on the decisions of major investors. For example, in Sichuan, there is a large capacity for automobile cover moulds. Jiangsu has a strong ability to precision die, and the users of molds are not local.

Third, the development focus and prospect of stamping die

The selection of development priorities should be determined based on market demand, development trends and current conditions. It can be described separately according to product focus, technical focus and other key points.

1. The development focus of stamping die products. There are 7 sub-categories of stamping dies, and some types are called by their service objects. At present, there is an urgent need to develop automotive cover molds, multi-function, multi-station progressive die and fine die. These molds now have large contradictions in production and demand and have good development prospects.

The development of automotive cover moulds is focused on large and medium-sized cover moulds for medium and high-end cars with high technical requirements, especially for outer cover moulds. High-strength and unequal-thickness stamping dies and large multi-station progressive dies and continuous dies will have a faster development in the future.

The development of multi-functional, multi-station progressive die is focused on high precision, high efficiency and large, high life progressive die.

The development focus of the precision die is the large precision die of the thick plate precision die, and the precision is continuously improved.

2. The development focus of stamping die technology. The future development trend of mold technology is mainly toward the development of informationization, high-speed production and high precision. Therefore, from the perspective of design technology, the focus of development is to promote the application of CAD/CAE/CAM technology and continuously improve efficiency, especially the computer simulation analysis technology of sheet metal forming process. Mold CAD and CAM technology should be developed in the direction of pleasant, integrated, intelligent and networked, and improve the degree of specialization of mold CAD and CAM systems.

In order to improve the application level of CAD, CAE and CAM technologies, it is very important to establish a complete mold database and develop expert systems and improve the practicality of the software. From the perspective of processing technology, the focus is on high-speed machining and high-precision machining. High-speed machining is currently mainly the development of high-speed milling, high-speed grinding and high-speed electrical processing and rapid molding technology. High-precision machining is currently mainly to develop various precision machining of mold parts with a precision of 1 μm or less and a surface roughness of Ra ≦ 0.1 μm. It is also one of the key points in the development of stamping die technology to improve the standardization of molds and to improve the production and supply of mold standard parts.

In order to improve the life of the stamping die, various techniques such as strengthening and superhard processing on the surface of the die are also the development priorities.

For mold digital manufacturing, system integration, reverse engineering, rapid prototyping / mold manufacturing and computer-aided application technology to form a comprehensive solution, provide mold development and engineering services, comprehensively improve the enterprise level and mold quality, which is more stamping die technology The focus of development.

3. Other development priorities and prospects. The other development priorities and prospects are very rich. Here, we only analyze the three aspects of management, specialization and standardization, and industry adjustment.

Enterprise management is a systematic project, a science, and science and technology. Compared with mold companies in industrialized countries, in a sense, our management is lagging behind technology. Therefore, it is very important to improve management, and the tasks are heavy. At present, the management of mold enterprises has many forms, each with its own adaptation targets. However, it is a development direction to do a good job in information construction and gradually realize information management. The industry also has a consensus on this.

Due to historical and institutional reasons, the level of mold specialization and standardization in China has been very low, and the specialization of stamping dies is lower than that of plastic molds and die-casting molds. This hinders the development of stamping dies to a certain extent. According to the specialization of molds at home and abroad, specialization can have multiple meanings: 1) mold production is independent of other products, specializing in the production of molds; 2) pressing molds Type division, specializing in the production of certain types of molds (such as stamping dies); 3) In a certain type of mold, according to the service object or mold process and size, select a certain mold in the mold (such as automobile cover Specialized production of molds, multi-station progressive molds, fine-punching molds, etc.; 4) Specializing in the production of certain parts of the mold (such as mold bases, punches, elastic components, etc.) to the mold manufacturing enterprises; 5) The process carries out professional collaboration. For example, companies that specialize in mold design in the society, companies that specialize in cavity processing or electrical processing, companies that specialize in measurement or heat treatment, and companies that specialize in polishing business, etc. The development of the mold industry. However, the road to specialization is still far away, and it is necessary to speed up the process to adapt to the situation. Therefore, this is also the focus of development.

Industry adjustment is a very arduous task, especially in the mold industry. The adjustment tasks faced by the mold industry mainly include:

(1) Adjustment of the organizational structure of the mold enterprise. It is the direction of adjustment to make the mold factory (workshop) independent and become an independent legal person facing the society and self-financing. Mold enterprises develop in a small but precise, small and specialized, small and special direction, and the combination of enterprises under the condition of mature conditions, as well as the development of a combination of production, learning, research and science, industry and trade. The direction of adjustment. The scale effect has also attracted everyone's attention.

(2) Adjustment of mold product structure. With the development of the automotive industry, electronic information industry and home appliance industry, the stamping die market structure is undergoing great changes. In line with this, the stamping die product structure must be adjusted accordingly. For example, automotive cover molds, automotive parts precision die, high-precision and difficult lead frame die, connector multi-station progressive die, various motor stator and rotor progressive die, etc., the product type and output will be very large Development, the relevant enterprises must adjust their product structure according to market demand. In general, the proportion of large, precise, complex, long-life molds with increasing technical content should be continuously improved.

(3) Adjustment of the technical structure of the mold. The 21st century has entered the information age, and the development of the information age is changing with each passing day. To develop the mold industry and enterprises, we must grasp the pulse of the times and consciously and actively adjust our own technical structure. The traditional mold design and manufacturing technology must be transformed with advanced and applicable high-tech. The technical content of the mold will be gradually and rapidly improved, and the modern industrial enterprise management technology will gradually replace the workshop-style management mode. The mold industry and mold companies can only be in an invincible position in the ever-changing market economy by continuously adjusting the technical structure.

(4) Adjustment of the mold import and export structure. In 2005, China's stamping die imports were 726 million US dollars, and exports were 197 million US dollars. After import and export, the net import was 529 million US dollars, and the ratio of import and export was 3.7:1. China's stamping die exports account for only 5% of production. Such a structure is obviously unreasonable. In developed countries of the mold industry, mold output generally has about 30% of exports, and the export molds are much larger than imported molds. Although we can't reach the same import and export structure in developed countries in the mold industry in a short period of time, we are striving to expand exports and gradually improve the structure. After several years of hard work and try to achieve the basic balance of import and export, it should be our goal of adjustment.

Today, with the development of industrialization driven by informatization, as the trend of economic globalization is accelerating, China's stamping dies must be improved as soon as possible. Through reform and development, and taking various effective measures, under the joint efforts of all employees in the stamping die industry, China's stamping dies will certainly continue to improve and gradually narrow the gap with the world's advanced level. During the "Eleventh Five-Year Plan" period, under the guidance of the scientific concept of development, we will continuously improve our independent development capabilities, attach importance to innovation, adhere to reform and opening up, take a new road to industrialization, and gradually shift the speed-effective growth model to the quality and level of efficiency. The level of stamping dies in China is bound to rise to the next level.