1、 Technological measures to improve the productivity of machining

（1） Reduce single work

First, technological measures to shorten the basic time. In mass production, because the basic time accounts for a large proportion in the unit time, the 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 cutting amount, cutting speed, feed rate back draft, which is an effective method widely used in machining to improve productivity. However, the improvement of the cutting parameters is restricted by the tool durability, machine power, process system stiffness so on. With the appearance of new cutting tool materials, the cutting speed has been improved rapidly. At present, the cutting speed of carbide turning tool can reach 200m / min, that of ceramic cutting tool can reach 500m / min. In recent years, the cutting speed of polycrystalline synthetic diamond polycrystalline cubic boron nitride tools for cutting ordinary steel is up to 900m / min. In the aspect of grinding, the development trend in recent years is high-speed grinding strong grinding.

2. Adopt multi cutter cutting at the same time.

3. The method of multi part machining is to reduce the cutting in cutting out time of the tool make the basic time coincide, so as to shorten the basic time of each part processing to improve productivity. There are three ways of multi-component processing: sequential multi-component processing, parallel multi-component processing parallel sequential multi-component processing.

4. Reduce machining allowance. Using the advanced technology such as precision casting, pressure casting precision forging to improve the manufacturing accuracy of the blank reduce the machining allowance, so as to shorten the basic time, sometimes even without further machining, which can greatly improve the production efficiency.

Second, shorten the auxiliary time. The auxiliary time also accounts for a large proportion in the single piece time, especially after greatly increasing the cutting amount, the basic time is significantly reduced, the proportion of auxiliary time is higher. At this time, taking measures to reduce the auxiliary time has become an important direction to improve productivity. There are two different ways to shorten the auxiliary time, one is to make the auxiliary action realize mechanization automation, so as to directly reduce the auxiliary time; the other is to make the auxiliary time coincide with the basic time, so as to indirectly shorten the auxiliary time.

1. Directly reduce the auxiliary time. Using special fixture to clamp workpiece, workpiece does need to be aligned in clamping, which can shorten the time of loading unloading workpiece. In mass production, efficient pneumatic hydraulic clamps are widely used to shorten the loading unloading time. In order to shorten the time of loading unloading workpieces, the combined fixture adjustable fixture can be used in small batch production. In addition, in order to reduce the auxiliary time of shutdown measurement in machining, the active detection device digital display device can be used to measure in real time in the process of machining, so as to reduce the measurement time needed in machining. The active detection device can measure the actual size of the machining surface during the machining process, automatically adjust the machine tool control the working cycle according to the measurement results, such as the grinding automatic measurement device. The digital display device can continuously accurately display the movement angular displacement of the machine tool in the process of machining adjustment of the machine tool, which greatly saves the auxiliary time of shutdown measurement.

2. Shorten the auxiliary time indirectly. In order to make the auxiliary time coincide with the basic time in whole in part, the method of multi position fixture continuous machining can be used.

3. Shorten the time of working place arrangement. Most of the working time is spent on tool change, so it is necessary to reduce the number of tool changes the time required for each tool change. 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 tool adopting the tool fixture. Such as the use of a variety of quick change tool holder, tool fine-tuning mechanism, special tool template tool sample automatic tool change device, etc., to reduce the loading unloading of the tool the time required for tool setting. For example, the use of indexable carbide cutting tools on lathes milling machines can only reduce the number of tool changes, but also reduce the time of tool loading unloading, tool setting edge grinding.

4. Technological measures to shorten preparation end time. There are two ways to shorten the preparation end time: first, expand the production batch to reduce the preparation end time allocated to each part; second, directly reduce the preparation end time. To expand the production batch of products, it can be realized through the standardization generalization of parts, the group technology can be used to organize production.

（2） Implement the care of multiple machine tools

It is an advanced labor organization measure to take care of multiple machine tools. It is obvious that one worker can improve productivity by managing several machine tools at the same time, but two necessary conditions should be met: first, if one person is in charge of M machine tools, the sum of the working hours of any M-1 machine tool should be less than that of the other machine tool; second, each machine tool should have an automatic stop device.

（3） Adopt advanced technology

1. Rough preparation. The new technology of cold extrusion, hot extrusion, powder metallurgy, precision forging explosive forming can greatly improve the precision of blank, reduce the workload of machining, save the raw materials, obviously improve the productivity.

2. Special processing. For hard, tough brittle materials complex surfaces, special processing methods can greatly improve productivity. If electrochemical machining is used for general forging die, the machining time can be reduced 40-50 hours to 1-2 hours.

3. Adopt less no cutting. Such as cold extrusion gear, rolling screw, etc.

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

（4） Adopt automatic manufacturing system

The automatic manufacturing system is an organic whole composed of a certain range of objects to be processed, a certain level of flexibility automation of various equipment high-quality people. It receives external information, energy, funds, supporting parts raw materials. Under the joint action of human computer control system, it realizes a certain degree of flexible automatic manufacturing, finally outputs products documents Materials, wastes environmental pollution. The use of automated manufacturing system can effectively improve labor conditions, significantly improve labor productivity, significantly improve product quality, effectively shorten production cycle, significantly reduce manufacturing costs.

2、 Design measures to improve machining productivity

In the design, on the premise of ensuring the use performance of product parts, it is necessary to make the parts structure have good processing technology, materials with good processing technology, so as to reduce the processing difficulties, improve the labor productivity, obtain good economic benefits.

（1） Improve the structure technology of parts

In order to make the mechanical products have good structural technology, the following measures are often adopted in the design:

1. Improve the degree of "three modernizations" of parts components (parts standardization, parts generalization product serialization), make the best use of the mastered technology, standardized serialized parts components, try to borrow the same type of parts produced by our factory, so that the designed structure has good inheritance.

2. Adopt parts with simple surface geometry arrange them on the same plane axis as much as possible to facilitate processing measurement.

3. Reasonably determine the manufacturing accuracy of parts assembly accuracy of products. On the premise of ensuring the use performance of products, the manufacturing accuracy assembly accuracy shall be minimized.

4. Increase the proportion of parts made by non cutting method parts made by cutting method with lower cost. Obviously, the larger the proportion of these two parts in the product, the better the technological performance of the product.

（2） the workpiece material with good cutting performance

The machinability of workpiece materials directly affects cutting efficiency, power consumption surface quality of parts. In order to improve the productivity reduce the cutting cost, we should the workpiece material with good cutting performance take heat treatment measures to improve the cutting performance of the material on the premise of ensuring the use performance of the product.

The machinability of materials mainly depends on their physical mechanical properties. Generally speaking, materials with high strength hardness, good plasticity toughness, poor thermal conductivity have poor machinability, vice versa.

In practical production, heat treatment is often used to change the metallographic structure mechanical properties of the material, so as to improve the machinability of the workpiece material. For high hardness cast iron, high temperature spheroidizing annealing is generally used to spheroidize flake graphite, so as to reduce the hardness improve the machinability of the material.

Conclusion:

Improving the production efficiency of machining is only the renewal of process concept, but also the improvement of management concept. Advanced cutting tools machine tools are used to achieve high-speed efficient cutting. At the same time, relevant technologies management methods are used to optimize the whole processing technology, various ways are used to improve the processing efficiency to achieve high-speed cutting. Efficient cutting, efficient machining. The ultimate goal.