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Do you know the technological measures to improve the productivity of machining? Next, the editor of Xiehe Processing Factory will give you a detailed introduction.

(1) Shorten the working hours of a single piece

First, technological measures to shorten the basic time. In mass production, since the basic time accounts for a large proportion of the unit time, productivity can be improved by shortening the basic time. The main ways to shorten the basic time are as follows:

1. The basic time can be shortened by increasing the amount of cutting, increasing the cutting speed, feed rate and back cutting amount. This is an effective method widely used in machining to improve productivity. However, the improvement of the cutting amount is restricted by the durability of the tool, the power of the machine tool, and the rigidity of the process system. With the emergence of new tool materials, the cutting speed has been rapidly increased. At present, the cutting speed of cemented carbide turning tools can reach 200m/min, and the cutting speed of ceramic tools can reach 500m/min. The cutting speed of polycrystalline synthetic diamond and polycrystalline cubic boron nitride tools that have appeared in recent years to cut ordinary steel can reach 900m/min. In terms of grinding, the development trend in recent years is high-speed grinding and powerful grinding.

2. Use multiple cutters to cut at the same time.

3. Multi-piece processing This method is to improve productivity by reducing the cutting-in and cutting-out time of the tool or overlapping the basic time, thereby shortening the basic time of each part processing. There are three ways of multi-piece processing: sequential multi-piece processing, parallel multi-piece processing, and parallel sequential multi-piece processing.

4. Reduce machining allowance. Advanced technologies such as precision casting, pressure casting, and precision forging are used to improve the manufacturing accuracy of blanks and reduce machining allowances to shorten the basic time. Sometimes, machining is not even required, which can greatly improve production efficiency.

Second, shorten the auxiliary time. Auxiliary time also occupies a large proportion in the single piece time, especially after the cutting amount is greatly increased, the basic time is significantly reduced, and the proportion of auxiliary time is even higher. At this time, taking measures to reduce auxiliary time becomes an important direction to improve productivity. There are two different ways to shorten the auxiliary time. One is to mechanize and automate the auxiliary action, thereby directly reducing the auxiliary time; the other is to make the auxiliary time coincide with the basic time, and indirectly shorten the auxiliary time.

1. Directly reduce the auxiliary time. The workpiece is clamped with a special fixture, and the workpiece does not need to be aligned during clamping, which can shorten the time for loading and unloading the workpiece. In mass production, high-efficiency pneumatic and hydraulic fixtures are widely used to shorten the time for loading and unloading workpieces. In single-piece small batch production, due to the limitation of the manufacturing cost of special fixtures, in order to shorten the time for loading and unloading workpieces, combined fixtures and adjustable fixtures can be used. In addition, in order to reduce the auxiliary time of shutdown measurement during processing, active detection devices or digital display devices can be used for real-time measurement during processing to reduce the measurement time required during processing. The active detection device can measure the actual size of the machined surface during processing, and automatically adjust the machine tool and control the work cycle according to the measurement results, such as the automatic measurement device for grinding. The digital display device can continuously and accurately display the movement amount or angular displacement of the machine tool during the machining process or the machine tool adjustment process, which greatly saves the auxiliary time of stopping the measurement.

2. Indirectly shorten the auxiliary time. In order to fully or partially overlap the auxiliary time and the basic time, the method of multi-station fixture and continuous processing can be used.

3. Shorten the time for setting up work. Most of the time for arranging work is spent on changing tools, so the number of tool changes must be reduced and the time required for each tool change must be reduced. Improving the durability of the tool can reduce the number of tool changes. The reduction of tool change time is mainly realized by improving the installation method of the tool and adopting the tool fixture. For example, various quick-change tool holders, tool fine-tuning mechanisms, special tool-setting samples or sample pieces, and automatic tool-changing devices are used to reduce the time required for tool loading and unloading and tool setting. For example, the use of indexable carbide insert tools on lathes and milling machines not only reduces the number of tool changes, but also reduces the time for tool loading and unloading, tool setting and sharpening.

4. Technological measures to shorten the preparation and termination time. There are two ways to shorten the preparation and termination time: first, expand the production batch of products to relatively reduce the preparation and termination time allocated to each part; second, directly reduce the preparation and termination time. The expansion of product production batches can be realized through the standardization and generalization of parts, and the production can be organized by group technology.

(2) Implement supervision of multiple machine tools

Taking care of multiple machine tools is an advanced labor organization measure. It is obvious that a worker can manage several machine tools at the same time to improve productivity, but two necessary conditions should be met: First, if one person is in charge of M machine tools, the sum of the worker’s operating time on any M-1 machine tools should be less than another Second, each machine tool must have an automatic parking device.

(3) Using advanced technology

1. Blank preparation. Using new technologies such as cold extrusion, hot extrusion, powder metallurgy, precision forging, and explosive forming can greatly improve the precision of the blank, reduce the workload of machining, save raw materials, and significantly increase productivity.

2. Special processing. For extra-hard, extra-tough, extra-brittle and other difficult-to-process materials or complex profiles, the use of special processing methods can greatly improve productivity. If the general forging die is processed by electrolysis, the processing time can be reduced from 40 to 50 hours to 1 to 2 hours.

3. Use less and no cutting processing. Such as cold extrusion gear, rolling screw, etc.

4. Improve processing methods, reduce manual and low-efficiency processing methods. For example, in mass production, broaching and rolling are used instead of milling, reaming and grinding, and fine planing, fine grinding and diamond boring are used instead of scraping and grinding.

(4) Adopt automated manufacturing system

The automatic production system is an organic whole composed of a certain range of processed objects, various equipment with a certain degree of flexibility and automation, and high-quality people. It accepts external information, energy, funds, accessories and raw materials, etc. Under the joint action of the computer control system, a certain degree of flexible and automated manufacturing is realized, and finally the products, documents, waste materials and environmental pollution are output. The use of automated manufacturing systems can effectively improve labor conditions, significantly increase labor productivity, greatly improve product quality, effectively shorten production cycles, and significantly reduce manufacturing costs.

The above content is the technical measures to improve the productivity of mechanical processing, and I hope it can be helpful to everyone. If you want to know more about cnc processing, please call Xiehe processing factory, we will serve you wholeheartedly.