China Be-Cu Prototype company specializes in the production and sales of automobile frames and related auto parts, with an annual output of more than 10,000 frames. However, the status of the order models of the frame series in the workshop is complex, and the sheet metal parts of the frame are diversified. Most of the stamping parts are processed by outsourcing. The annual outsourcing cost is high, and the delivery cycle is long, often due to the production load and the parts cannot be supplied in time. , resulting in a significant reduction in the production efficiency of the frame, so how to improve the backward production technology and technical transformation of the processing and production of frame sheet metal parts has become the company’s key research projects.
Considering that in recent years, various composite processing equipment has been used and paid attention by more and more machinery manufacturing enterprises[1-2]At present, the more advanced processing machines on the market are mainly high-speed punching and cutting machines, among which the WHiTnEY-3400XP high-speed punching and cutting machine is suitable for the production of frame sheet metal parts.
Introduction of WHiTnEY-3400XP high-speed punching and cutting compound machine
The main features of WHiTnEY-3400XP high-speed punching and cutting compound machine (hereinafter referred to as compound machine) are high production capacity, good precision, wide range, low operating cost and small footprint.
At present, the company’s frame sheet metal production mainly includes flat parts (front and rear axles, engine reinforcement plates), U-shaped non-variable section parts (frame beam), L-shaped non-variable section parts (girder connecting plate), front and rear of the frame, Most of the tail longitudinal beam and related small parts can be processed by the compound machine.
Comparison of advantages and disadvantages of application of composite machining
1.Analysis of past processes
The previous process flow is shown in Figure 1.It can be seen from this that the process is complex, and there are many people using it, the number of equipment required is large, the floor space is large, and the energy consumption is high, and the drilling accuracy of the hanging drill is generally 1-2mm. In terms of ensuring product quality consistency, Multiple flips cause repeated clamping errors to accumulate[3]often lead to difficult assembly of castings and related accessories, more drilling dies, and higher maintenance costs.
2.Import MFP process analysis
The process flow is now used, see Figure 2.The base material is sheared by the shearing machine, positioned and sent to the compound machine for one-time hole cnc machining. After forming, it is sent to the bending machine for bending, which greatly reduces the processing time and reduces the multiple turnovers of the belly surface and the upper and lower wing surfaces.[4].
3.Comparison of advantages and disadvantages of composite machining
By comparing the production process before and after the application of the compound machine, we can see that after the introduction of the compound machine, the parts are processed into one piece, the workpiece positioning is accurate and fixed, and the workpiece is made with high precision. The high-speed plasma cutting is used, the production time is interrupted, and the efficiency is high; It is small, the utilization rate of the site is high; there are few input personnel, few procedures, high degree of automation, and no manual work is required in the processing process. The disadvantage is mainly the high cost of initial investment.
Economic Feasibility Analysis of Application of Compound Machine
1.Unit cost of composite machine
Based on the estimated production of 2,020 buses, 862 Chinese buses, 4,127 full-load buses, 2,799 buses, and about 30% (840) of leaf spring buses in the factory in 2016, the data provided by the manufacturer and the actual production are provided in combination with the equipment. After calculation, the equipment production cost can be obtained, as shown in Table 1.
2.Analysis of self-made parts imported into composite machining
At present, the self-made workpieces of the frame mainly include the frame beam and the tail longitudinal beam. The production of beams mainly includes shearing, profile cutting, radial drilling and drilling. The processing cost of a single piece is 10.67 yuan, while the cost of a single piece of composite machining is 7.7 yuan, and each piece can save 2.97 yuan. The processing of the tail longitudinal beam is mainly carried out by the shearing machine, and the drilling hole. Taking 2016 as an example, after the introduction of the compound machine, the processing efficiency increased by 86%, and the annual saving amount was 69,470 yuan. The specific data is shown in Table 2.
3.Analysis of the recycling of purchased parts into composite machining
At present, the purchased parts can be processed in-house by the compound machine, mainly the outer wall panels of the full-load engine, the outer wall panels of the full-load front and rear axles, the outsourced beams of the frame, and the frame longitudinal beams and the upper piece connecting plate, which are respectively represented as parts 1~Part 4, cost data, see Table 3. The outer wall panels are commonly used parts for large and medium-sized buses and buses, and the latter two are the rear-mounted chassis of large and medium-sized buses and the beams and connecting plates commonly used in buses. The demand is large and the price is high. The self-made processing of the compound machine can save a lot of costs. .
4.Processing Analysis of Material Utilization Improvement
The layout of the plate is optimized by applying a high-speed punching and cutting compound machine, and the number of parts in a row is increased from 8 to 9, which improves the utilization rate; in the past, it was cut by a shearing machine, and the excess materials were mostly used to make the sealing plate, which was costly. , the profit is low, and the remaining material removed by the copy cutting machine parts can not be used, and the gap and surrounding parts of the parts can be used after compound machining, and additionally purchased recycled parts (backing plates, valve bracket lights) are arranged to improve the utilization rate of waste. Reduced outsourcing costs and higher profits. For the plasma cutting plate, the margin reserve is large, so that the utilization rate of the plate is improved. After the comprehensive application of the compound machine, the utilization rate of the remaining material has reached 97.8%, which is 12.5% higher than that of the previous process.
5.Tangible and intangible benefits of equipment introduction
Combining the above items, the change of production cost after adopting the new process is obtained, as shown in Table 5.
- Tangible benefits: After the project is introduced, 2,506,079 yuan can be saved every year. Calculated at a discount rate of 10%, the equipment purchase cost can be recovered in 2 years and 4 months. If the discount rate is 8%, it can be shortened by about another month, that is, 2 years and 3 months. Therefore, the purpose of reducing costs is achieved.
- Intangible benefits: After the project is introduced and self-made, the efficiency is increased by 86%, the production process and benefits are improved, and the maximum benefits can be achieved through effective management.
It can be seen that the introduction of the high-speed punching and cutting compound machine not only reduces the manufacturing cost, but also improves the production efficiency.
Conclusion
By introducing a high-speed punching and cutting compound machine, the current bottleneck problem of untimely supply of materials can be solved, and the self-made productivity in the factory can be improved, the production efficiency can be improved, and the cost of outsourcing and self-made can be reduced. It has high degree of automation, strong flexible processing ability, reliable performance, convenient operation, stable product quality, low operating cost, and fully meets the requirements of multi-variety and mass production.[5], which is more conducive to the expansion of the main business of the factory in the future.
The composite machine has great advantages in process practicability, equipment applicability, long-term use of equipment, technological breakthroughs, and technical reserve for a long period of time, and it is coordinated with the existing laser machines for processing. Complementary use will greatly boost the factory’s business and influence within its peers, which will greatly improve the core competitiveness of the manufacturer.
Sheet fabrication services for mild steel, high strength low alloy (HSLA) steel, cold/hot rolled steel, galvanized steel, stainless steel, aluminum, copper and brass. Capable of fabricating parts up to 12 ft. length and +/-0.001 in. tolerance. Various capabilities include contract manufacturing,custom stamping,edge rolling, forming,top laser cutting, roll bending and welding. Finishing and secondary services such as hardware installation, tapping, deburring, cleaning, heat treating, plating, anodizing and painting available. Sheet Metal Prototype and low to high volume production runs offered. Suitable for commercial/residential architectural, aluminum brake shape parts, wall panel systems, brackets, general flashings, rails, call button plates and ship building component parts.