High Speed Machining (HSM) generally refers to machining at reasonable speeds and high surface feed rates. For example, in the processing of aluminum cylinders and cylinder heads of engines, the material removal rate is very high. This processing is what we call high-speed machining. High-speed machining enables us to process quality-qualified parts in as short a time as possible, improving a company's market response. Therefore, high-speed machining is receiving more and more attention from the manufacturing industry, especially in the new construction of enterprises. When constructing new factories, new projects, and production line transformations, they will give priority to efficient processing methods, that is, comply with the development trend of high-speed machining in the industry. Meet the lean production requirements of the production line, effectively reduce manufacturing costs, and make the products produced competitive. High-speed machining is a systems engineering that requires a combination of aspects to create a complete high-speed machining. In all aspects, in addition to the high-speed processing machine tool plays a decisive role in the whole process, the tool is also a very important factor in high-speed machining. Therefore, the selection and management of the tool is very important, and it needs to be carefully considered and carefully planned in the implementation. .
First, the choice of tools
In order to ensure the balance between equipment efficiency and line tempo in the process, it is necessary to consider the appropriate tool to match the equipment in the production line. Therefore, the rationality of tool selection will directly affect the quality of the workpiece and the processing efficiency. Therefore, the selection of the tool should be carried out from the following aspects:
Processing equipment
The first is to understand the performance of the processing equipment, only to understand the performance of the equipment, you can use the right tool to match, otherwise, regardless of the choice of equipment or tools alone, its efficiency can not be played. Relevant information in recent years has shown that a tool worth tens of thousands of yuan may affect the efficiency of a device worth several million yuan. During the planning process, the design and arrangement of the tools largely determines the manufacturing costs and tooling costs during the production phase.
2. Tool material
With the rapid development of manufacturing technology, the requirements for cutting tools are getting higher and higher. In order to meet the requirements of high-speed cutting, new material tools have been widely used. The use of new material tools has greatly improved the cutting efficiency. The durability of high cobalt, high vanadium, high performance and high speed steel tools can be increased by 1.5-3 times compared with ordinary high speed steel, and the strength of powder metallurgy high speed steel can be increased by 20%-30%. The toughness is improved by 1.5-2 times, and the reliability is obviously improved compared with the ordinary high-speed steel, while the CBN (cubic boron nitride), PCD (polycrystalline diamond) tools and ceramic tools represent the superhard tools of today's technological development level, cutting speed. It can be several times higher than cemented carbide and greatly improve processing efficiency.
3. Tool holder
As the cutting speed of the tool holder increases, the coupling performance of the spindle/shank changes greatly under the action of centrifugal force, which directly affects the machining accuracy and surface roughness of the workpiece. Therefore, it is suitable for the tool clamping of CNC machine tools and high-speed machining. And its connection with machine tools, such as HSK shank, hot shank, hydraulic shank, and other new shanks are widely used.
4. Tool structure
In order to improve production efficiency and reduce tool change time, various composite tools such as drill collar compounding, drilling hinge compounding, drilling and threading compounding are increasingly used in the processing of automotive parts. . The complex unfolding tool meets many special processing requirements, and some tools have even developed into a machine, electric and hydraulic integrated device, which has far surpassed the traditional tool concept; due to the large number of powertrain processing It is the production of flowing water. The production of the previous process directly affects the production of the next process. In order to improve the production efficiency and reduce the production cost, a large number of combined tools and the resulting non-standard tools are used.
5. Cost of the tool
Tool consumption is related to many factors and requires specific analysis. While looking at the total tool consumption costs, it is more important to look at the tool costs consumed by a single piece of processed product. Not only the direct tool cost, but also the impact of the tool on production efficiency and the resulting total manufacturing cost. The performance, life and purchase price of the new knives have a great impact on the cost of the tool. The number of regrindable tools, the number of regrinds and the cost of grinding also have a significant impact on the total cost of the tool; therefore, Considering the relationship between disposable equipment and tool investment and long-term tool consumption costs requires a comprehensive consideration and balance.
6. Process method
In order to give full play to the role of high-efficiency flexible wires, the tool has put forward many new requirements for the process. For example, the same tool can be used to process more different processes of the same workpiece, and efforts are made to reduce the amount of tool inventory, limit the frequency of tool change, and reduce Manufacturing costs, etc. At the same time, special tools, composite tools or intelligent tools should be designed for some technical difficulties to solve the problems between machining accuracy and machining efficiency.
7. Tool supplier
The choice of tool includes the determination of the tool supplier. Since cutting is a system problem, process changes, machine tools, fixtures, cutting fluids, and cutting parameters all have a significant impact on the life of the tool, and the structural form of the tool itself, the material of the tool, and the surface coating that affect the machining performance. The determination is also closely related to the process, cutting parameters, cutting fluid, and the like. The selected tools must pass the cutting test, and the selected tools and their suppliers are determined after the cutting test. At the same time, the modern automobile manufacturing industry also requires the tool supplier not only to provide the overall machining solution, but also to provide timely and effective on-site technical support. Form a partnership with automotive manufacturing companies.
Second, the management of the tool
The cutting method adopts high-speed and high-efficiency processing. In theory, it should improve production efficiency. However, for the production line that implements the flow operation, whether the production efficiency can be truly improved requires scientific management of the production line tools. In order to ensure that the production line can obtain the required, sufficient quantity and excellent cost performance of the tool in time, effective control must be carried out on the maintenance and maintenance of the tool, pre-adjustment and detection, and tool life. When machining problems or tool problems occur, the production line is quickly responded and supported, and the problems are quickly analyzed and solved, so that the production can be carried out normally and the losses are reduced to a minimum. Therefore, the management of the tools is carried out in the following aspects: :
1. Tool durability and frequency of tool change, length of tool change
The above factors directly affect the machine start-up rate, the tool life should be set reasonably, and the tool change time should be strictly controlled. It is necessary to consider how to minimize the downtime of the production line equipment when changing the tools on one machine. To consider how far the tool wears, the tool can be used to achieve better sharpening results and the longest tool life.
2. Bottleneck equipment on the production line
It is necessary to control the efficiency of each equipment on the production line and achieve the same efficiency through work. Otherwise, the high efficiency brought by high-speed machining cannot be realized due to the bottleneck effect of some equipment on the production line.
3. Tool pre-adjustment and detection
The pre-adjustment and detection of high-efficiency machining tools is extremely important. The qualification rate of the adjustment tool has a great influence on the production efficiency. Therefore, it is necessary to consider a perfect system and a series of management to ensure that the production line is timely and meets the required quantity. Tools, and get quick response and support in the event of machining problems or tool problems, quickly analyze and solve problems so that production can proceed normally.
4. Prevention and control of abnormal tool consumption
Strengthen the prevention and control of abnormal tool consumption, and try to control various variables that may cause abnormal tool consumption, such as the blank quality of the workpiece, the stable operation of the machine tool, the quality of the cutting fluid, the quality stability of the tool and its coating, and Consistency, etc., must take all necessary and effective control measures and preventive measures.
5. Tool maintenance and maintenance
Establish a tool maintenance system similar to equipment maintenance, and regularly perform precautionary maintenance on disassembled, cleaned, and lubricated tools with complicated structures.
Third, the conclusion
In the face of the challenges of modern manufacturing, both flexible and efficient production, in the face of increasingly fierce market competition and the pressure to continuously reduce manufacturing costs, the rationality of tool selection and the level of tool management are very important for high-speed machining. In particular, it has a greater impact on production efficiency and manufacturing costs. In today's fierce market competition, the scientific selection of tools and effective management of tools will significantly improve production efficiency, effectively reduce manufacturing costs, and enable enterprises to be in a favorable position in the fierce competition.
