Mon Jul 04 15:54:41 CST 2022
The efficiency of metal removal per unit time in machining is called metal removal rate (Q), metal removal rate Q=ae×ap×F/1000, where ae is the width during cutting and ap is the depth during cutting. F is the feed amount of the cutting tool in the cutting process. It can be seen that the main method to improve the processing efficiency, that is the metal removal rate is to increase the values of ae, ap and F. That is to say, high-speed machining is not the only way to efficiently process. We can also increase the amount of ae, ap and single tooth cutting. The way to improve efficiency is what we usually call heavy cutting. Therefore, high-efficiency machining includes high-speed machining and large margin machining. The cutting tools selected for high-speed machining and rough machining have their own pertinence in design concepts and manufacturing processes.
High-speed machining uses high-speed and high-feed methods for processing. Its processing advantages are that it requires less cutting force, the degree of workpiece deformation and system vibration is very low, which is conducive to improving workpiece accuracy, form and position tolerances and surface quality. It is mostly used in aviation thin-walled parts, difficult-to-process materials, mold cavity processing and batch processing of products. High-speed machining cutting tools must have good wear resistance, strength and reasonable geometric structure parameters, and have strict requirements on the dynamic balance system. Therefore, advanced tool materials and coatings must be selected for cemented carbide insert. The new "V" series products launched by Pinding in 2008 are mainly for high-speed machining in the mold industry and aerospace industry. This series of tools use ultra-fine grain size. The material contains 12% Co, and the composite coating of AlCrN and TiAlN is selected at the same time. The surface hardness exceeds HV3700. The tool adopts short edge and unique groove design to ensure the rigidity of the cutting tool during high-speed rotation and smooth chip removal. The cutting tool is recommended for cutting Rotation speed is greater than 12000r/min
Heavy cutting processing adopts the processing method of large feed or large cutting volume, which is mainly suitable for large margin roughing. It is characterized by high metal removal rate, but the cutting conditions are harsh, the cutting force is large, and the requirements for machine and cutting tools are high. Need to have enough rigidity and power, and the cutting tool should have enough toughness and chip space. At the same time, the cutting tool adopts high-strength, unequal and unequal spiral design ideas to reduce the cutting force during the cutting process of the tool and slow down the thermal wear of the tool. Pinding has successively introduced chip dividing tool, back wave cutting tool (BW series) and unequal spiral tool (R series) for rough machining and difficult-to-machine materials.
In addition to achieving high-efficiency cutting by improving cutting parameters, we can also improve processing efficiency by continuously optimizing processing technology and reducing processing procedures. In particular, it is widely used in hole processing. For example, we use step drills, step reaming or drill reaming and other combined tools to reduce processing procedures and improve production efficiency. At the same time, we can also use the form of welding superhard tool materials on the cutting edge of the cutting tool to improve tool life, and improve production efficiency by reducing the number of tool changes, such as welding diamond (PCD), cermet (Al2O3) and cubic nitrogen Boron (CBN) and so on. This type of mature product is included in the samples of German original drill and hinge products newly launched by Pinding in 2009.
With the gradual improvement of the grade of processing machine tools and the continuous optimization of the processing technology, the combination of high-speed machining and heavy-cutting processing will better improve the processing efficiency. Usually, heavy-cutting tools are used for large margin cutting and semi-finishing during roughing. High-speed machining cutting tools are selected for processing at the time or in the finishing process, and the reasonable combination use can fully improve the processing efficiency, ensure the quality requirements, and reduce the production cost. Therefore, efficient processing has attracted more and more attention from the machinery industry, occupying the leading processing position in the entire industry.