德语
In recent years, natural resources such as iron ore and coke required to produce automobile steel have become increasingly tight. Improving material utilization can not only reduce the manufacturing cost of automobiles and improve the competitiveness of automobile brands, but also conform to the environmental protection concept of energy conservation and consumption reduction.
Process optimization
Optimize blanking sampling to reduce waste
For some special-shaped stamping parts, the arrangement of blank sheets in the unrolled blanking mold can be optimized to reduce waste, unroll as much blank sheets as possible, and improve material utilization.
Figure 1 shows the sampling optimization of the blank sheets in the blanking mold of the left and right inner longitudinal beams of the T6 model. The original output of one sheet is optimized to produce two sheets in one step, reducing the weight of the waste, and increasing the material utilization rate of the left and right inner longitudinal beams from 78.2% to 87.6%.
Combined material specifications to reduce waste
In order to improve market competitiveness and enrich the sales product line, automobile factories will invest in new models every year, and new specifications of materials will be generated for new models. When the mass production of the vehicle model is over, the corresponding special steel will occupy inventory due to slow consumption. Therefore, every addition of a new specification of steel will increase inventory and management costs. Automobile factories must ensure the versatility of steel as much as possible and reduce the number of steel varieties.
Figure 2 shows the optimization process of the outer panel of the hood of the T6 model. The outer panel of the hood of the T6 model is 1330mm, and the unwinding step is 1820mm, and the blanking mold is required; while the outer panel of the hood of the X7 model is 1830mm, and the blanking is cut with arc-shaped swing shears, and there is no waste.
Figure 2 Diagram of optimization process for hood outer plate arrangement of T6 models
Since the unwinding step of the T6 hood is similar to the material width of the X7 hood roll material, through on-site verification, the X7 hood roll material can be used to produce the sheet of the T6 hood according to the parameter of 1170mm step distance.
Through process optimization, the material utilization rate is increased by 3.7%, while reducing the steel specifications for the outer plate of the original T6 hood are reduced, increasing the versatility of the material and reducing inventory and management costs.
Mold design optimization, one mold and multiple pieces
When producing multiple parts on a set of molds at the same time, one or more small parts are produced using waste from the holes of large parts to achieve the effect of improving material utilization.
The molds of the inner panel of the hood of the B5 model and the inner panel of the T7 door (Figure 3) use waste in the holes of the inner panel of the hood and the inner panel of the door respectively to stamp out the hood reinforcement plate parts and door lock reinforcement plates, avoiding the use of materials alone to produce the hood reinforcement plate and the door lock reinforcement plate.
Figure 3: Multi-piece, schematic diagram of the set and use of a set
Mold design optimization, slab combination
When designing the mold, the left and right symmetrical parts are designed together to form. Through process optimization, two parts are stamped out by two sheets into one sheet and two parts are stamped out by two sheets, reducing the process supplement area and improving material utilization.
Figure 4 shows the mold design of left and right rear door outer panel parts of MX3 model and the mold design of left and right rear door outer panels of M44 model. The left and right rear door outer panels of the MX3 model stamp a part with one piece of material, and the process supplement surface is required in all four directions of the parts; while the left and right rear door outer panels of the M44 model stamp two parts with one piece of material, which is equivalent to reducing one process supplement surface. Through comparison, the utilization rate of the M44 model's rear door exterior panel material is 4.16% higher than that of the MX3 rear door exterior panel material material.
Figure 4 Mold design comparison diagram
Material size optimization reduces blank size
By adjusting the positioning of the blank sheet material in the drawing mold, the process supplement of excess materials other than the drawing ribs is reduced, thereby reducing the size of the blank sheet material required by the parts and improving the utilization rate of the material.
Figure 5 is a cross beam part under the front window of the T/B model. Observing the drawing forming transition parts, it was found that there was a large part of the blank sheet material in the process supplement area of the drawing part. Through measurement, the unwinding step of this part was reduced from the original 590mm to 560mm, and the drawing mold was grounded and the sheet positioning device was adjusted. After appearance inspection and three-coordinate measurement of geometric dimensions, it was confirmed that when the sheet step was reduced by 30mm, the parts were formed normally and the quality was in compliance with the standards.
