Stamping production costs accounted for 39% of the total cost of the automobile production by rational utilization of plank, stamping process and right to choose the appropriate stamping can effectively reduce the production cost of manufacture equipment and has great significance to the control of the vehicle manufacturing costs.
Stamping production cost 39% of the cost of the vehicle production, in the stamping production cost, stamping steel material cost accounts for 91%, so in the vehicle production cost control, stamping production to reduce costs, improve material utilization, has become a top priority.
The elements of material
1. Material and material thickness
In product design when select material, avoid to choose high grade of material caused by excess product performance, at the same time, on the premise of meet the requirements of product, process, try to choose existing models used in the mass production material, material thickness, forming material platform, provide convenience for the subsequent procurement, inventory management. Such as ordinary manufacture key performance requirements is its ductility, so in accord with the request of the quality of the product as far as possible choose low grade of material. And for the selection of the material thickness, in addition to consider the strength of the body after forming, weight, and attention to the popularization of material thickness. Because of the special material thickness, suppliers, it is difficult to supply and the price is high.
2. Plank roll wide choice
In the steel plate specifications species, whether scale plate or coil plate, the same material, material thickness of material, volume wide different selling prices. So, want to reduce the cost, from purchasing volume wide fluctuation kongfu, on the premise of guarantee the material utilization as far as possible choose not premium volume wide range. As for scale board as far as possible to choose the appropriate size, from steel mills, after the completion of shear needn't to secondary shear, reduce cost of shear; For rolled plate, as far as possible choose uncoiling forming coil specification and process, to reduce the workload of the secondary shear, improve work efficiency.
3. The choice of thickness deviation
The thickness of the plate there is a deviation request, usually in the range of deviation permit, should first choose the deviation of the plate, thus saving purchasing cost.
Pay attention to in the design of the product cost control
1. Build platform steel material specifications
As new models launched on the market to speed up the speed, steel procurement varieties also continue to increase, designers make the most of the existing materials should be paid attention to during the design specifications, at the same time, enterprises should be based on the existing materials specifications, build material specifications platform in craft, the purchasing department.
2. According to the model production timely adjust material purchase specification
Car companies in the production model is more, the output of various models is different, should pay attention to combining the production batch number and purchasing, for small production models, design specifications, special attention should be paid to reduce the model material specifications mergers, For larger production models, can be appropriately increased material procurement varieties.
Cutting method
1. Using a pendulum shear mode instead of straight improve material utilization
Shown in figure 1, the left the graph is ordinary straight cut way, if the blank size parts is the shape of the dotted line in the figure, the figure of the dotted line and the line between the materials is redundant. The right way for the pendulum shear, using pendulum shear line cut off directly on the dotted line position, improve the material utilization.
Figure 1 straight cut (left) and pendulum shear (right).
2. The use of suit cut
Different plate shear size can be split. Such as two parts blank size is 580 mm, 580 mm, with width of 1200 mm, 1200 mm coil uncoiling shearing, each two parts will produce waste 40 mm and 160 mm wide. If the two parts on the bike at the same dosage, can use 1000 mm wide coil, a shear can have two parts, no waste is generated.
3. The blanking die blanking
Blanking die or progressive die is proposed, which can make full use of the remaining material, improve the production efficiency and material utilization.
4. Appropriate split more than expected
For some materials specifications, may be used to a lot of kinds of parts, usually is not a material specification for each parts is appropriate, there may be more than expected. For can use more than expected, the remaining material shear is necessary, on the other hand is superfluous, can adopt the way of excess stock split reduces shear. For example, some parts of blank size is 180 mm * 1240 mm / 6 mm, open book size is 180 mm * 1250 mm, 180 mm x 10 mm of visible shear more than expected, if the remaining material cannot be used, under the condition of the mold to allow, can adjust the mould, to divide the remaining material, cut off waste in stamping process directly.
Blanking process of improvement
1. Reduce or cancel the boundary value
Shown in figure 2 a (on) and b (on) of yanbian set in JB/T9176 the stamping material consumption process ration establishment method is recommended requirements, if when making mould debugging on is too big, can change the mold decrease or cancel on, improve material utilization.
Figure 2 boundary value by illustrations
2. Change the parts blank dimensions by the piece of material to the material
According to the actual circumstances of the mold piece can be expected (one module and one or the one module and two pieces of the blank material) to the material (the obtained blank layout, set a certain interval, one out of many blank material). Generally USES the material shape of blank size of the most pressing is small, has a high material utilization. For larger size sheet billet parts, change to the material, the weight will increase, limited by handling the problem, not suitable for use the blank material. So to think of some way to the piece of material with large stamping blank into a blank, as shown in figure 3, the blank dimensions by the block material with parts to strip material, sheet material utilization increased by 20.97%, increased investment in some handling tools or sling, improve the harvest benefit is very big, is worth the investment relative to income.
Figure 3 article will block material blank into the blank
3. The positive and negative direction set
According to the positive and negative direction blanking parts shape timely select it to operate some trouble, but to improve the material utilization effect is obvious.
The forming process of improvement
1. Reduce the boundary value
The boundary value under the blanking process to reduce the content of the same, just process is different, you can refer to the blanking process reduce the boundary value method.
2. Instead of shallow drawing forming
This is the stamping process to improve the product, by changing the forming process, reducing the blank size parts.
In addition, you can use one module and two or one module and two cavities, improve work efficiency.
The use of excess stock
1. Will have the use value of the remaining material directly to produce small parts
Can be cut or stamping of remaining material used in the production of small parts, reduce the use of normal sheet, improve material utilization.
2. To sorting specifications larger flat materials sold separately
For large pieces of sheet metal, useful if you can't use, it can be classified according to type sale, improve the waste, sales value, increase income.
3. Be sure to provide more than material supporting manufacturers and materials processing
For enterprises with supporting manufacturers, sheet metal can also be available to provide supporting manufacturers, the processing mode, reduce procurement costs, increase profits.
Other improvements
1. Stamping process merging
Merge multiple parts stamping process, reduce the amount of working procedure, the improvement in reducing process to improve efficiency at the same time, also can consider to reduce on combined, as well as blank dimensions to improve, improve material utilization. Before, for example, some parts to improve the stamping process of drawing, trimming, punching and flanging, plastic, punching - side trimming, separation, through technology improvement, you can change the process to blanking, forming, while reduce process, blank size is reduced.
2. Mold operation conditions in accordance with choice of machine tools
This is the most basic requirements, trying to identify the situation of "big horse car", you can choose the most economic and reasonable stamping machine, reduce energy consumption, improve efficiency.
3. The improvement of the dual mode or multimode in one
Consider stamping process of process requirement and machine tools, can be installed on the same machine at the same time two sets of mould or more sets of mould, the parts of one-time production of multiple processes, improve work efficiency.
conclusion
The stamping production to reduce costs, improve the utilization ratio of material improvement measures, is based on the professional field to improve the experience summary, as long as we have the courage to explore, diligently study, found that the scene of the waste and unreasonable, the improved method above, on-site improvement combined with product and process design, we can create greater efficiency.