1. Overview of Toyota Mould Design and Manufacturing Department
Toyota Motor Corporation mainly has two departments related to Stamping Die design and manufacturing. Among them, the eighth production technology department is responsible for mold design, and the st department is responsible for mold manufacturing (st is the abbreviation of stamping die). They all directly belong to the head office, the production technology department 1-8 belong to the production preparation department, and the die department (st department) belongs to the machine manufacturing department.
1. The 8th Production Technology Department
Its main responsibilities are mold design and stamping equipment preparation. In addition, there are nearly 350 people in its planning, production preparation, subordinate departments and other departments. Among them, there are three technical rooms related to mold design, which are divided by the types of product parts engaged in:
Each room is divided into two groups: stamping process and die structure design.
Specialized division of labor is the characteristic of Toyota’s mold design department
a. Die design content breakdown
Toyota divides mold design into three processes: process design, mold surface design, and structural design. The division of labor is clear, and specialized personnel are responsible for them. Process design mainly completes process sketches, dl drawing design, detailed mold design task books, mold surface ideas, etc. The main creative work of mold design is completed by the human brain in this step. The mold surface design is almost a pure curved surface, and the focus of the structural design is on the concrete realization of the mold structure.
b. Subtle specialization of personnel
Each room is only responsible for one type of product parts, and each person is responsible for the same part or even the same type of mold within a certain period of time. Since Toyota develops up to ten new cars each year, that is to say, some people may draw ten very similar drawing dies for the front door outer panels in a year, and the degree of specialization can be imagined.
c. Social division of molds
Japan’s mold manufacturing has a strong division of labor. Although Toyota has strong mold manufacturing capabilities, it does not do everything. For example, he is responsible for the coordination of the stamping process of all parts of the entire vehicle and the entire vehicle of the mold, but he is responsible for the mold design and manufacturing only for the interior and exterior covering parts of the body, and the floor and beam parts are all outsourced to the designated manufacturers. Not only Toyota, but also mold factories affiliated to major foreign automobile companies, such as the mold factory of Daihatsu Corporation in Japan, even only make a limited number of outer covering parts such as side panels, fenders, and top covers. This can be seen as a development trend, and even professional mold manufacturers in South Korea and Taiwan are developing in a more professional direction that only produces a few parts.
2. Mould Manufacturing Department (ST Department)
Toyota’s st department is responsible for the coordination of mold manufacturing and new vehicle molds, and the preparation of stamping production until mass production.
3. Toyota’s mold design and manufacturing capabilities
- Mold design and manufacturing capabilities: Approximately 10 car molds can be developed every year;
- Mold output (standard sets) about 2000 sets/year
- Internal control rate 60% (40% for outsourcing)
- Among the main products: molds account for 80%
- Inspection tools accounted for 7%
- Other accounted for 13%
- Complete annual mold manufacturing cost budget of nearly 20 billion yen
- Per capita mold output is 2 standard sets/person. year
- Mold manufacturing cost (excluding design) about 6 million yen/set
- Man-hour cost (average) about 10,000 yen/hour
- Vehicle mold design and manufacturing cycle 12 months
- (From the completion of the body design to the mass production of the new car)
- Including the entire vehicle mold design cycle of 5 months
- Manufacturing cycle 5 months
- Commissioning cycle 6 months
It can be seen that Toyota’s annual car production capacity is about 5 million (about 50% in Japan), which is ten times that of mainland China’s car production, and its mold design and manufacturing capacity is several times that of our national automobile mold production capacity. . Toyota’s vehicle mold manufacturing cycle is far shorter than our general single mold manufacturing cycle. Its standard single mold manufacturing cycle is three to four months, which is still a dream in our opinion. The quality level of our molds is far from that of Toyota.
4. Toyota’s general mold manufacturing cycle
Toyota standardizes the mold manufacturing plan, which can be divided into short cycle, standard cycle and long cycle according to the complexity of the mold.
1.The total cycle time of a single set of drawing dies is 62 days, of which the manufacturing cycle is 52 days
The above cycle includes the design and manufacture of the mold until the completion of the first trial of the mold. If you consider the total cycle time of each sequence mold of the product, and the total cycle time of each sequence mold of a single product, 22 days shall be added to the drawing mold (including mold debugging, but not including vehicle debugging), a total of 84 days .
The above days are all working days (except holidays). When converted into a calendar day, about 20 days equals one month, which means the manufacturing cycle of a single set of molds is three to four months.
Toyota’s mold manufacturing is also carried out in accordance with the just-in-time production method, all inverted plans, and it is planned that every working day will not be put into production in advance to avoid adding more molds in production. Our inverted plan is often to rush the construction period and artificially compress the construction period. Toyota’s inverted plan is to produce necessary products when necessary to avoid the waste of overproduction caused by early production.
2. Toyota Mould Manufacturing Technology
In the past ten years, I have conducted more in-depth studies and inspections in many mold manufacturing plants in Japan, and the accumulated time has been more than 6 months. After comparison, it is found that Toyota’s mold technology is also very prominent among Japanese mold manufacturers, and it is worthy of being a world-class level in terms of ability, efficiency and technology. Through the understanding of Toyota, we can see that the world’s automotive mold manufacturing technology is developing in these directions: computer operations are gradually replacing on-site operations, high-precision processing is used to replace human manual labor, mold design and manufacturing are highly standardized, and single-piece The development of production methods to assembly-line production methods and so on. Combined with our domestic mold manufacturing situation, Toyota is very different from us in the following places, which is worthy of our good reference.
Stamping process design
a. Fine mold surface design
The mold design we often say is actually divided into three parts: stamping process design, die surface design and structural design. The content and focus of these three designs are completely different. Toyota’s work process is to first design the stamping process and then guide the die surface design and die structure design. They are done by different people, and the division of expertise is very clear. The traditional stamping process design uses process drawings or dl drawings. Its die surface design is very rough. The process modeling under the guidance of such drawings must be manually trimmed and made up by the manufacturing process, resulting in mold manufacturing. The amount of manual clamp repair is large and the cycle is prolonged. Toyota completed the fine design of the die surface through computer curved surface modeling during the design stage. For example, various drawbeads are designed for different feed rates, different cross-sections of drawbeads in different parts of the same die set, anti-rebound, over-drawing treatment, minimum blanking surface design, unequal gap design for convex and concave dies, etc. As a result of the fine mold surface design, it can greatly reduce the surface processing, reduce the clamp repair, and reduce the trial time. Its effect is very important.
In contrast, the domestic mold design is still in the structural design stage, the mold surface design is not paid much attention to, and the mold surface is actually completed by the day after tomorrow. It is not surprising that the backward mold design has caused the backward manufacturing. .
b. Application of sheet metal forming analysis technology
Toyota started to use the finite element method for computer simulation of sheet metal forming analysis 5-6 years ago. The main solution software used is dyna3d in the United States. It took nearly three years of hard work to reach the practical level. At present, Toyota has established a database of analysis results of various typical parts of the entire body. For a part of a new car model, if there is not much change in the formability, just refer to the original process and do not analyze it. Only the special new model can be analyzed for sheet metal forming. Toyota’s new car is to be prototyped. In addition to sheet metal forming analysis for special-shaped parts, a simple model is generally used for verification. Therefore, Toyota people believe that the current sheet metal forming analysis is not a necessary and simple thing, whether it is cycle or cost, it has a great price.
In my opinion, Toyota has a large amount of vehicle development, little changes between models, many similar parts, and accumulated a wealth of human experience. Sheet forming analysis does not have much use. It is a good idea to establish a database of analysis results. Method (Japan’s Fuji Mould Company also does this). In contrast to the current domestic situation, on the one hand, the specialization of mold factories is very low, and various parts will be encountered. It is difficult to have ready-made experience, and it seems that sheet metal forming technology is more needed. On the other hand, the technical level is low and the supporting environment is poor (such as: sheet material parameters, friction coefficient, etc.) are difficult to grasp. It is also very difficult for mold factories to achieve practicality (research regardless of the effect or cost) is also very difficult. Even if a professional analysis company is established, considering the number of users, cycle time, price and other factors, I am afraid it will be too high and too few. At present, the actual application effect of this technology in China is still difficult to conclude.
c. Die surface design experience accumulation mechanism
In addition to manual sketching, Toyota’s design department has been computerized. The general designer has a laptop in addition to a workstation. However, the truly creative design still relies on the human brain, especially the accumulation of human experience. Toyota places special emphasis on the experience accumulation mechanism: only collective experience cannot have personal experience, such as: unified management of data, group discussion of sketch design, multi-departmental collective review of drawings, frequent additions and changes to design standards and specifications, etc. .
The experience accumulation mechanism is the main means for Toyota to continuously improve the fine design of the die surface. For example: After the mold is processed, the mold surface does not need to be lapped, the cutting edge does not need to be in the gap, the fitter is only responsible for installation, and the mold cannot be adjusted at will during the first trial of the mold. The mold face designer is present for the first trial of the mold. Defects need to be recorded. The final rest results, such as drawbeads, draw fillet changes, asymmetry of symmetrical parts, etc., must be measured on site. The accumulation, sorting, analysis, and archiving of these materials are all the experience accumulation of die surface design, and can be added to the next design at any time.
Toyota’s mold design and debugging process is truly a closed-loop manufacturing system. With the help of this self-improving experience accumulation mechanism, mold design is becoming more and more refined and more accurate.
d. Clearance diagram design
In Toyota, the mold surface design is actually completed by the two parts of surface modeling and nc programming. In order to convey and describe the mold surface design ideas, a third type of diagram except the dl diagram and the mold diagram—gap is produced. The diagram is also called the quality assurance diagram.
I have not seen the gap map before, and this may be a creation of Toyota. The design of the mold is not simply to design a machine, it can complete its certain actions (this can only be called structural design), and the ultimate goal of mold design is to ensure that the products it presses are qualified and high-quality Yes, the gap diagram is such a diagram designed to ensure the quality of the product. The quality assurance chart mainly includes the following items: the actual mold surface area, the gap value of each symbol area, the change of the mold surface required by the process, the change of the drawing fillet, the hollowing out of various mold surfaces, etc. Wait. Any die surface design that cannot be achieved through curved surface modeling is achieved through the transmission of the gap diagram and relying on the design of nc programming. Here, nc programming is no longer a simple realization of the processing of the mold structure, and it actually participates in the mold surface. Coming in design. Therefore, the application of clearance diagrams is also a necessity for fine die surface design.
e. The impact of mass production on molds
Toyota’s production scale is world-class, and it has rich experience in how to adapt the mold design to the requirements of mass production.
Improve material utilization rate: For high-volume automobile production, improving the utilization rate of sheet materials is the number one priority in mold design. As long as the material utilization rate is increased by a few percentage points, the cost of the mold can be neglected. If a set of molds is 400,000 yuan, which is only equivalent to the price of 100 tons of steel plates, and based on a life of 500,000 pieces, an average of 0.2kg steel plates can be saved per piece, which is enough to save the cost of this set of molds.
Reduce stamping process: The trend of mold design is to merge parts, close the left and right symmetrical parts, close the front and back parts, etc. Originally several parts are combined into one part, and different parts are combined in a set of molds, and the mold is getting bigger and bigger. , The single-piece process is greatly reduced, and the number of vehicle molds is getting less and less, which plays a key role in reducing the cost of stamping. For example: Toyota reduced the mold coefficient of the whole vehicle parts from the past three points to about 2.
Stamping automation: In order to adapt to the full automation of the stamping line, the mold must take into consideration the unloading of the manipulator, the automatic discharge of the waste, the general use of pneumatic, automatic and sensor devices, and so on.
Quick mold replacement: The mold change time of the stamping line has also become a problem that must be considered in mold design. For example, the drawing die is completely replaced by single action instead of double action, the die is automatically clamped, and the ejector pin is not exchanged for die change, etc.
Design and processing of mold structure
Design has two purposes: one is for design itself, the other is for manufacturing. The designer gradually perfects his design ideas during the drawing process. After the drawing is finished, he is also clear. Therefore, the designer must first see the drawings conveniently and make the design work more efficient. On the other hand, design should be oriented towards manufacturing, with the ultimate goal of improving production efficiency.
We should realize that different production processes determine the form of expression of drawings. The traditional form of mold assembly drawing plus parts drawing is suitable for the production of molds with non-frame structures. After adopting large-scale CNC milling, the mold assembly drawing becomes a better form. After the full application of cad design, if the production method does not change, then the two-dimensional design and general drawing design will not change, just replace the drawing board with a screen and a keyboard. Our company once changed the two-dimensional design to three-dimensional solid design in 1997, but the effect was not good, the design efficiency was reduced, and the production was not much benefit.
Toyota has provided us with relatively successful experience in the close cooperation between CAD 3D solid design and manufacturing.
a. Physical design
Toyota’s mold design has all adopted three-dimensional solid design, and the software used is enginner.
Separation of mold surface design and structural design: Toyota completely separates mold structure design from mold surface design. The former is a solid design, and the latter is still a curved surface design. In the structural design, the part of the mold surface is only schematic, and can be used for real-type processing, but not for mold processing. This division of labor greatly simplifies the design of the mold entity, and this simplification is very important to the success or failure of the three-dimensional entity design.
Cancel two-dimensional drawings: Dimensioning accounts for about 40% of the drawing workload. Toyota does not draw two-dimensional drawings in the traditional sense, so this part of the workload is completely omitted. Instead, according to the needs of each process, the necessary three-dimensional sketches and the plan sketches with the necessary dimensions are given. If you start with a three-dimensional design and finally get the result of a two-dimensional picture, it will be very time-consuming and laborious to transform a three-dimensional entity into a two-dimensional picture that conforms to people’s habit of viewing pictures. The designed entity becomes worthless. Obviously contrary to the original intention of the physical design, Toyota’s success is not to do so.
Building blocks and editing design: 3D entity design adopts building block design, relying on three-dimensional standard parts and typical structure library, so that the mold structure is greatly standardized, and the two-dimensional drawing concept is changed into a three-dimensional layout. At the same time, a large number of existing similar mold structures are borrowed, and the new mold design is completed after simple editing and modification. This is a conceptual revolution for designers. If you still stick to the rules and first draw a plan to regenerate your body shape, the advantages of 3D design will become a burden and the efficiency will be too low.
Interference check: In two-dimensional design, designers often do not really establish a three-dimensional mold image, and can only rely on cross-sectional diagrams for complex spatial problems. Once insufficient experience and inadequate consideration, spatial interference is inevitable. The most direct benefit of 3D solid design is the very intuitive and convenient interference check, and it can even be used for motion interference analysis. An old and difficult problem in the past two-dimensional drawing design was solved in front of the physical design.
Elimination and simplicity in physical design: physical design is directly oriented to manufacturing, and the complexity and simplicity of its design are determined by processing needs, and there is no need to consider people’s habit of viewing pictures. For example: the chamfering of the casting, the concave corner is finished by the tool in the processing, and the convex corner is trimmed manually, so there is no need to do it in the design; another example: standard parts, which are completely purchased parts, can also become indicative in the design Simple geometry and so on. There are also many design tasks, which are actually completed by subsequent process specifications, such as the position of the screw hole, the shape of the insert, and so on. Designing for processing needs is the most economical design.
Semi-automatic design: On the basis of physical design, Toyota has developed auxiliary programs with certain functions for drawing dies and other molds with typical structures and relatively high standardization, so as to achieve semi-automatic design. For example, the drawing die structure design is generally handed over to novices and female staff, and it takes less than a week to design a set of die.
b. Real CNC machining
The first purpose of the physical design is that the casting foam is completely processed by CNC. Toyota’s solid mold is CNC machined with a block of rectangular foam. Real-type numerical control processing and production is through the process editing of the solid model (such as: processing allowance on the processing surface, layered editing of the model, etc.), and then through numerical control programming, foam blank blanking, numerical control processing, manual bonding and Finishing and other processes are completed. In Toyota, the actual production employees have completely changed from manual production to a large number of CNC programming. The simple manual bonding and trimming work on site is performed by temporary workers. The actual numerical control production directly benefits the physical design, but also improves the accuracy of the casting, which brings great advantages to the subsequent fine processing.
c. CNC machining of structural surfaces
The mold structure surface is the machined surface other than the mold surface, such as: guide surface, insert mounting surface, screw hole, other surfaces to be processed, and so on. These are also produced by programming and CNC machining in Toyota. The physical design brings the possibility of NC programming and processing of the structural surface of the mold. Programming of structural surface processing can greatly improve machining efficiency, reduce human operation errors on site, and increase the degree of automation of processing. Of course, to do this, in addition to physical design, there are many tasks to be done, such as automatic tool setting, tool management, machining parameters, programming experience, etc. In this regard, the gap between us and Toyota is even greater, without these foundations. , It is impossible to program and process the structural surface.
Toyota truly achieves the integration of cad/cam on the mold structure through physical design, and only by integration, can the physical design show its value by removing the constraints of drawing two-dimensional drawings. The two should develop simultaneously and complement each other. This is the experience Toyota provides us.
Mold surface processing is the focus of mold processing. Toyota has vigorously developed high-precision mold surface processing technology in recent years and has achieved refreshing results.
a. High-precision machining of profile
The high-precision machining of the surface is mainly reflected in the following aspects: improving the machining accuracy of the die surface, improving the degree of processing in place, and realizing the fine design of the die surface. In addition to machine tool accuracy and tool management, high-precision machining is mainly achieved by the improvement of programming technology.
Machining methods include contour line processing, maximum length forward cutting processing, finishing cutting travel density up to 0.3mm, and high-speed processing with a 30-degree angle for vertical cutting to improve processing accuracy.
At the same time, the concave corners should be cleaned, convex fillets should be processed in place, the unequal spacing of the mold matching should be controlled, and the maximum possible reduction of the symbol surface should be processed in order to achieve the fine processing of the mold surface.
b. High-precision machining of two-dimensional cutting edges
Toyota’s two-dimensional cutting edge insert processing adopts a dedicated insert processing line, and the single piece is processed into a living. The processing accuracy can reach the level of pin positioning and assembly, and the mold clamping does not need to adjust the gap. When the two-dimensional cutting edge is processed as a whole, the method of online measurement is also used to ensure the clamping gap of the convex and concave molds. The biggest advantage of the high precision of the two-dimensional cutting edge is to ensure that the trimming burr of the part is well controlled.
c. The effect of high-precision machining
Toyota uses high-precision machining to achieve the goal of less fitter and no fitter on the mold surface. In Toyota’s standard plan, between the completion of machining and the first mold trial, there are only seven fitter working days. It is basically fitter assembly time, but no fitter grinding time. In Toyota, once the mold is processed, there is basically no need to round corners, no gaps, no root repairs, wrong cutting edges, no grinding, and even the drawing die’s profile does not need to remove knife marks or push grinding. The only thing is The pliers repair is to use oilstone to push and grind the convex fillet and the blank drawing surface. Moreover, the qualification rate of the trial-pressed parts that do not need to be repaired in the first mold trial is over 80%. If you don’t see it with your own eyes, it is hard to believe, this is the power of fine die surface design and high-precision machining.
a. Mold material
Toyota’s drawing die materials mainly use nodular cast iron instead of alloy cast iron that is currently popular in China. Nodular cast iron has good welding performance, machinability, wear resistance and surface quenching hardness, and the cost is much lower than that of alloy cast iron. For the trimming edge material, the choice of profile inserts instead of conformal cast steel is mainly because the cost of cast steel is much higher. The most notable thing is that Toyota has now used a large number of special cast iron materials that integrate the base and the cutting edge as the trimming mold, which greatly reduces the machining cost of the mold. Please note that the cutting edge here is neither surfacing nor steel. The integral cutting edge of cast iron is only flame-quenched on the surface, and it is directly used for the thin-sheet trimming die with a life span of hundreds of thousands of times. Moreover, the cost of such castings is not high.
b. Surface treatment
The surface treatment of Toyota’s drawing model surface requires high electroplating, and other molds, flanging and trimming cutting edge inserts are basically flame quenched. Japan does not currently use ion nitriding technology, according to Toyota, there are also considerations for trial use. For the long-life cutting edge material of thick plates, Toyota uses special steel with its own patent, which is also flame quenched. The method of forming first and then quenching the whole, due to the deformation caused by quenching, can only be repaired manually, which is not used in Toyota.
c. Inspection in mold production
Molds are produced in a single piece, and it is very difficult to ensure quality. Most domestic mold factories are equipped with a large number of full-time process quality inspectors, which seriously affects production efficiency, but the quality control effect is not good. How does Toyota do it?
Process inspection: Toyota people believe that product quality is at the source. Design, technology, programming, machine tools, and cutting tools are the real guarantees of quality. Quality is produced rather than inspected. Therefore, there is no full-time inspection between molds. Only self-inspection and mutual inspection, the quality control is depended on every producer.
Surface inspection: There is basically no measurement and inspection on the mold surface. A large number of surface inspections, such as measuring the drawing fillet, the correction amount of the drawbead, and the smoothness of the curved surface, are mainly for the accumulation of experience in the design of the die surface, not for checking whether the quality of the die is qualified.
Product inspection: Toyota’s product inspection mainly relies on three-dimensional measuring machines for automatic numerical inspection, but they also do inspection tools, which only serve as product positioning support. Therefore, the inspection tool has a simple structure and does not have a forced clamping device. Their product inspection is almost in a free state. This is a very strict requirement for the conformity of the product.
Technological development trends
In the past few years, we have seen that the automotive mold industry in developed countries seems to be shrinking. Because, at that time, it was believed that mold production was inseparable from human manual labor. In developed countries, there were factors such as high wage costs and no one willing to work in this industry. The mold industry had a tendency to shift to the third world. Through Toyota’s development, we have gained some new insights. Mold production is increasingly dependent on high technology, which can completely reduce manual labor. The most important demand for mold production in automobiles is high quality and short cycle time. In large-scale automobile production, the cost of the mold itself is far less important than the cost of using the mold. From this point of view, our current mold production does not have any advantages, and this industrial transfer will not become a trend. Over the past ten years, the technological progress we have obtained through the introduction of hardware technology has not been improved by others. Efforts to pursue new gaps brought about by technological progress. To put it another way, if the automobile mold industry really shifts to the third world, it must be a sunset industry. At present, there is still a certain development space and demand for automobile molds without breakthrough changes in body materials.
1. Focus on the development of computer technology
The focus of Toyota’s mold manufacturing technology development is to highlight the application of computers, and more and more people are moving from the production site to the front of the computer. The physical design plus numerical control programming replaces manual actual production and machine tool operation. Fine mold surface design and fine CNC programming greatly reduce clamp repair, and high-precision machining eliminates mold research and repair. Now the CNC programmers have surpassed the on-site operators, the man-hour cost of CNC programming has exceeded the machining man-hour cost of the machine tool by 50%, and the programming cycle has exceeded the machining cycle. The development of computer technology application has not reduced the cost of molds at present, but mold production has shifted from relying on human skills to numerically controlled automatic and semi-automatic production. This high-precision and unmanned processing has improved the quality of molds and product parts. Great improvement, greatly shortened production cycle, and computer technology has brought mold manufacturing technology to a new level. By comparison, it can be seen that the current domestic computer applications are still relatively rudimentary. It is not that our machine tools and software are not good, but that there is a big gap in the basic technology of the application. It is not easy to achieve that effect.
2. Eliminate fitters
It turned out that we thought that it was impossible to leave the handwork for a product with a single-piece production and a complex profile, and Toyota proposed to eliminate fitters. Eliminating fitters is a goal, which mainly refers to greatly reducing or completely avoiding grinding and adjusting fitters (assembly fitters are still required). As we have introduced in the previous section, Toyota’s goal has been basically achieved. Except for the grinding of the drawn noodles and the drawn chamfers, most of them are abnormal or repaired by pushing grinding, mold repairing and adjusting pliers. Defects in design and manufacturing are no longer a necessary and normal job.
Let’s take an example. The smoothness of the drawn model surface has always been the quality standard that we emphasize. In the past, to achieve this, it was mainly done by fitters. In order to reduce or not push the grinding, it is necessary to reduce the margin of the milling cutter trace. Some people advocate the use of a five-axis milling machine for vertical profile processing, and some use CNC profile grinding. These Toyotas have also used them, but practice has proved that five-axis machine tools are costly, low in efficiency, programming is very difficult, and the effect is very unsatisfactory. Finally, Toyota adopts a high-speed, small-travel three-axis milling method to obtain high-precision profiles, and the fillets are manually ground, while other profiles are simply not ground, and the die faces are drawn with knife marks. The results show that although the mold face can’t talk about the finish (there is also a knife mark), even the outer panel of a car with high surface quality requirements, except for some pull marks on the inner surface of the part, has no effect on the outer surface of the useful part. Any adverse effects, that is, those mold surfaces that need to be plated, are also plated with knife marks. It is said that some auto mold factories in Germany and the United States have also abolished surface grinding. For those who pursue the surface finish of the mold, this is really a big joke of fate. Similarly, the concave corners of the molding surface are cleaned up, and the vertical surface processing uses a 30-degree head to prevent the knife, and the unequal gap is used to control the molding pressure of the part. Now the matching accuracy of the convex and concave molds makes the research and clamp repair lost. significance.
Therefore, the elimination of fitter in a sense is no longer a dream. Of course, in China, how to convince users to accept this kind of tool marks is still a big issue for a mold factory.
3. Integrated processing
Toyota’s machining workshop has three types of CNC machining lines: the first is a machining line composed of several CNC machine tools with interchangeable beds. One line includes bottom machining, horizontal milling, rough milling, and fine milling. The machine tool has a clear division of labor, and there is no need to re-install the card and correct the workpiece when changing the machine tool. This assembly line is about the product of the 1980s. The second type is a group of unmanned kneading processing machines with a three-dimensional warehouse, which was a product of the early 1990s. The third type is an integrated, high-speed, high-precision, five-sided machining center that has only been put into use in recent years. The first type of processing line, its single machine is the CNC machine tool we currently use, but the machine tool is a multi-work table, it is very efficient in terms of not reinstalling the card and correcting, and we basically stay at the level of single machine operation. It is worth learning from. For the kneading machine group, although it is very advanced, it is difficult to operate, and the preparation work and time are very long. If there is not a large number of finishing tasks, it is not practical to use, even in Toyota. It seems that this is not a success Direction. The integrated machining center is the latest technology currently under development. Its advantage is that it combines the advantages of various machine tools. In addition to the bottom surface processing, it can be installed at one time, with high power, high precision and high speed. The eighteenth class is proficient in all kinds of martial arts, and the processing efficiency is very high. The disadvantage is that the cost of the machine tool is high, and the environmental requirements are also high. Is it economical to use it for rough and heavy work together? Not yet known. But, undoubtedly this is a very idealistic technology, which represents the development of CNC machining technology and should attract our attention.
Toyota’s technology tells us: good molds should be designed; molds can also be produced on an assembly line; high-tech applications are the driving force for the development of mold manufacturing technology; there is still a big gap between the domestic automotive mold industry and the world’s advanced level. If you don’t work hard, this gap will not be narrowed, but will be widened.
Through the above, we just list together some impressive things that we have seen in Toyota, which are relatively strong in comparison with the domestic ones. They are not comprehensive or detailed. We hope that these materials can give colleagues thinking.
We feel that the gap between us and the world’s advanced level is a great pressure. In the face of the trend of world economic integration, if you are not the best in the world, you may not be able to stand at home. There are not many domestic auto mold manufacturers, but they are not full. Our high-quality mold market is occupied by mold factories in neighboring countries and regions. Can we survive without learning from the most advanced mold technology in the world?
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