<\/strong><\/h2>\n\n\n\nGeneral process code for turning (JB \/ t9168.2-1998)<\/p>\n\n\n\n
The extension of the turning tool holder should not be too long. Generally, the length should not exceed 1.5 times the height of the tool holder (except for turning holes, grooves, etc.)<\/p>\n\n\n\n
The center line of the turning tool bar should be perpendicular or parallel to the tool running direction.<\/p>\n\n\n\n
1. Adjustment of tool tip height:<\/p>\n\n\n\n
When turning the end face, the conical surface, the thread, the forming surface and the solid workpiece, the tool tip should be equal to the axis of the workpiece.<\/p>\n\n\n\n
Generally, rough turning, fine turning and tool tip should be slightly higher than workpiece axis.<\/p>\n\n\n\n
When turning thin long axis, rough hole and cutting hollow workpiece, the tool tip should be slightly lower than the workpiece axis.<\/p>\n\n\n\n
The bisector of the sharp angle of the thread turning tool should be perpendicular to the axis of the workpiece.<\/p>\n\n\n\n
When clamping the turning tool, the gasket under the tool bar should be less and flat, and the screw for pressing the turning tool should be tightened.<\/p>\n\n\n\n
2.Workpiece clamping<\/p>\n\n\n\n
1) When the workpiece is clamped with three jaw self centering chuck for rough turning or finish turning, if the diameter of the workpiece is less than 30mm, the overhanging length shall not be more than 5 times of the diameter; if the diameter of the workpiece is more than 30mm, the overhanging length shall not be more than 3 times of the diameter.<\/p>\n\n\n\n
2) When using four jaw single action chuck, flower plate, angle iron (bending plate) to clamp irregular heavy workpieces, counterweight must be added.<\/p>\n\n\n\n
3) When machining shaft workpiece between centers, the axis of tailstock center should be adjusted to coincide with the axis of lathe spindle before turning.<\/p>\n\n\n\n
4) When machining slender shaft between two centers, heel rest or center rest should be used. In the process of machining, we should pay attention to adjust the top tightening force of the center, and pay attention to the lubrication of the dead center and the center frame.<\/p>\n\n\n\n
5) When using tailstock, the sleeve should be extended as short as possible to reduce vibration.<\/p>\n\n\n\n
6) When the workpiece with small bearing surface and high height is clamped on the vertical lathe, the heightened claw shall be used, and the pull rod or pressing plate shall be added at the appropriate position to compress the workpiece.<\/p>\n\n\n\n
7) When turning wheel and sleeve castings and forgings, they should be aligned according to the surface that is not machined, so as to ensure the uniform wall thickness of the workpiece after machining.<\/p>\n\n\n\n
3.turning machining<\/p>\n\n\n\n
1) When turning step shaft, in order to ensure the rigidity of turning, generally the larger diameter part should be turned first, and then the smaller diameter part.<\/p>\n\n\n\n
2) When slotting the workpiece on the shaft, it should be done before finishing to prevent deformation of the workpiece.<\/p>\n\n\n\n
3) When finishing turning the shaft with thread, it is generally necessary to finish turning the unthreaded part after thread processing.<\/p>\n\n\n\n
4) Before drilling, the end face of the workpiece should be turned flat. If necessary, the center hole should be drilled first.<\/p>\n\n\n\n
5) When drilling a deep hole, the pilot hole is usually drilled first.<\/p>\n\n\n\n
6) When turning (\u03a6 10-\u03a6 20) mm holes, the diameter of the tool bar should be 0.6-0.7 times of the hole diameter to be machined; when machining holes with diameters larger than \u03a6 20 mm, the tool bar with clamping tool head should be generally used.<\/p>\n\n\n\n
7) When turning multi head thread or multi head worm, try cutting should be carried out after adjusting the exchange gear.<\/p>\n\n\n\n
8) When using the automatic lathe, the relative position of the cutter and the workpiece should be adjusted according to the adjustment card of the machine tool. After the adjustment, the trial cutting should be carried out, and the machining can be carried out only after the first piece is qualified. In the process of machining, attention should be paid to the wear of the cutter and the size and surface roughness of the workpiece at any time.<\/p>\n\n\n\n
9) When turning on the vertical lathe, when the tool rest is adjusted, it is not allowed to move the beam at will.<\/p>\n\n\n\n
10) When there are position tolerance requirements on the surface of the workpiece, try to finish turning in one clamping.<\/p>\n\n\n\n
11) When turning cylindrical gear blank, the hole and reference end face must be machined in one clamping. If necessary, mark the line near the gear indexing circle of the end face.<\/p>\n\n\n\n
4.error compensation<\/p>\n\n\n\n
Modern mechanical manufacturing technology is developing towards high efficiency, high quality, high precision, high integration and high intelligence. Precision and ultra precision machining technology has become the most important part and development direction of modern machinery manufacturing, and has become the key technology to improve the international competitiveness. With the wide application of precision machining, turning error has become a hot topic. Because thermal error and geometric error account for the majority of all kinds of errors of machine tools, reducing these two errors, especially the thermal error, has become the main goal. With the continuous development of science and technology, error compensation technology (ECT) appears and develops. The loss caused by thermal deformation of machine tool is quite large. Therefore, it is necessary to develop a high-precision and low-cost thermal error compensation system to correct the thermal error between the spindle (or workpiece) and the cutting tool, so as to improve the machining accuracy of the machine tool, reduce the waste products, and increase the production efficiency and economic benefits.<\/p>\n\n\n\n
Basic definition and characteristics of error compensation<\/h2>\n\n\n\n
The basic definition of error compensation is to artificially create a new kind of error to offset or greatly weaken the original error which has become a problem at present. Through analysis, statistics, induction and mastering the characteristics and laws of the original error, the error mathematical model is established to make the artificial error and the original error equal in value and opposite in direction as far as possible, so as to reduce the machining error and improve the accuracy of parts The accuracy of the measurement.<\/p>\n\n\n\n
The earliest error compensation was realized by hardware. Hardware compensation belongs to mechanical fixed compensation. To change the compensation amount when the error of machine tool changes, it is necessary to remake parts, calibration ruler or adjust the compensation mechanism. Hardware compensation can not solve the problem of random error and lack of flexibility. The characteristic of software compensation is that it can improve the machining accuracy of machine tool by using the advanced technology and computer control technology of various subjects without any change to the machine tool itself. Software compensation overcomes many difficulties and shortcomings of hardware compensation and pushes compensation technology to a new stage.<\/p>\n\n\n\n
Error compensation (Technology) has two main characteristics: scientific and engineering<\/h2>\n\n\n\n
The rapid development of scientific error compensation technology has greatly enriched the theory of precision mechanical design, precision measurement and the whole precision engineering, and has become an important branch of this discipline. The technologies related to error compensation include detection technology, sensing technology, signal processing technology, photoelectric technology, material technology, computer technology and control technology. As a new branch of technology, error compensation technology has its own independent content and characteristics. It is of great scientific significance to further study the error compensation technology and make it theoretical and systematic.<\/p>\n\n\n\n
The engineering significance of engineering error compensation technology is very significant, which includes three meanings: first, using error compensation technology can easily achieve the accuracy level that “hard technology” can only achieve at a great cost; second, using error compensation technology can solve the accuracy level that “hard technology” usually can not achieve; third, using error compensation technology can solve the problem that “hard technology” can not achieve; Third, under the condition of meeting certain accuracy requirements, if the error compensation technology is adopted, the cost of instrument and equipment manufacturing can be greatly reduced, which has very significant economic benefits.<\/p>\n\n\n\n
Generation and classification of thermal error in turning<\/h2>\n\n\n\n
With the further improvement of the accuracy requirements of machine tools, the proportion of thermal error in the total error will continue to increase, and the thermal deformation of machine tools has become the main obstacle to improve the machining accuracy. Thermal error of machine tool is mainly caused by thermal deformation of machine tool components caused by internal and external heat sources such as motor, bearing, transmission parts, hydraulic system, ambient temperature, coolant, etc. Geometric errors of machine tools come from manufacturing defects, matching errors between machine parts, dynamic and static displacement of machine parts, etc. Basic methods of error compensation<\/p>\n\n\n\n
To sum up and related references, it can be seen that turning errors are generally caused by the following factors:<\/p>\n\n\n\n
Thermal deformation error of machine tool; geometric error of machine parts and structure; error caused by cutting force; tool wear error; other error sources, such as servo error of machine shafting, CNC interpolation algorithm error, etc.<\/p>\n\n\n\n
There are two basic methods to improve the accuracy of machine tools: error prevention method and error compensation method.<\/p>\n\n\n\n
The error prevention method tries to eliminate or reduce the possible error sources through design and manufacturing. To a certain extent, the error prevention method is effective to reduce the temperature rise of heat source, balance the temperature field and reduce the thermal deformation of machine tool. However, it is impossible to completely eliminate the thermal deformation, and the cost is very expensive;<\/p>\n\n\n\n
The application of thermal error compensation law opens up an effective and economic way to improve the accuracy of machine tools.<\/p>\n\n\n\n
<\/strong><\/h2>\n<\/div>","protected":false},"excerpt":{"rendered":"Turning refers to lathe processing, which is a part of machining. Lathe processing mainly uses turning tools to turn the rotating workpiece. Lathe is mainly used to process shaft, disc, sleeve and other workpieces with rotary surface. It is the most widely used machine tool in machinery manufacturing and repair factory. The skills of lathe…<\/p>","protected":false},"author":2,"featured_media":20531,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[92],"tags":[],"jetpack_featured_media_url":"https:\/\/www.meetyoucarbide.com\/wp-content\/uploads\/2021\/04\/QQ\u56fe\u724720210424094436.png","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/posts\/20530"}],"collection":[{"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/comments?post=20530"}],"version-history":[{"count":0,"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/posts\/20530\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/media\/20531"}],"wp:attachment":[{"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/media?parent=20530"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/categories?post=20530"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/ko\/wp-json\/wp\/v2\/tags?post=20530"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}