China Shenzhen Perfect Precision Product Co., Ltd. company news

Turning threads is one of the most common processes for turning parts, so this article is an example of a common fault and solution for turning threads. When turning threads, there are various reasons for problems in the movement between the spindle and the tool, which may cause a fault in the thread turning process and affect the normal production, and should be solved in time. The following is a list of common faults and solutions. 1、Rough surface of thread   Failure analysis: The main reason for this problem is that the cutting edge of the turning tool is not smooth enough, the cutting fluid and cutting speed do not match the processed material, or the vibration generated during the cutting process.   Solution: Fine study the tool with oil or grinding wheel, choose the matching cutting fluid and cutting speed, adjust the position of various parts, and ensure the accuracy of each guide gap, so as to prevent the vibration generated during cutting.   2、Gnawing tool   Failure analysis: mainly due to the incorrect location of the turning tool installation, either too high or too low, and the workpiece clamping is not solid, the turning tool wear is too large   Solution: adjust the height of the turning tool, so that the tool tip and the axis of the workpiece is equal to the height   3、Random buckle   Failure analysis: The reason is that when the screw rotates for a week, the workpiece is not installed over the whole number of turns and caused.   Solution.   (1) When the ratio of lathe screw pitch and workpiece pitch is not an integer number, if the bed saddle is swung to the starting position by opening the opening and closing nut when the tool is retired, then when the opening and closing nut is closed again, the turning tool tip will not be in the spiral groove turned out by the previous tool, resulting in a messy buckle. The solution is to use the positive and negative turning method to return the tool, that is, at the end of the first stroke, do not lift the opening and closing nut, the tool along the radial exit, the spindle will be reversed, so that the turning tool along the longitudinal return, and then the second stroke, so that the reciprocating process, because the transmission between the spindle, screw and tool holder has not been separated, the turning tool is always in the original spiral groove, there will be no messy buckle.   (2) For threads where the ratio of the screw pitch to the workpiece pitch of the turning lathe is an integer number of times, the workpiece and the screw are rotating, and after lifting the opening and closing nut, at least wait for the screw to turn one turn before closing the opening and closing nut again, so that when the screw turns one turn, the workpiece turns an integer number of times, and the turning tool can enter the spiral groove turned out by the previous tool, so that there is no messy buckling. This way, the tool can be manually retired by opening the opening and closing nuts. This is a fast retreat, which helps to improve productivity and maintain the accuracy of the screw, while the screw is also safer. 4、Pitch is not correct   Failure analysis and solutions.   (1) Improper matching of the hanging wheel or incorrect position of the handle of the feed box, resulting in incorrect thread length, can re-check the position of the handle of the feed box or check the hanging wheel.   (2) The local incorrectness is due to the local error of the pitch of the lathe screw itself, so the screw can be replaced or partially repaired.   5、The middle warp is not correct   Failure analysis: The reason is that the eating tool is too big and the dial is not allowed, and it is not measured in time.   Solution: Check in detail whether the dial is loose when finishing, the finishing margin should be appropriate, the cutting edge of the turning tool should be sharp, and it should be measured in time.

To correctly operate CNC machine tools, to avoid problems caused by improper operation, we need to understand and master the composition of CNC machine tools and work steps, the next I will introduce you to the composition of CNC machine tools and work steps:. CNC machine tools consist of four components: CNC unit, servo system, position feedback system, and mechanical parts of the machine pair. Here we understand the four components one by one.   CNC unit is the core of CNC machine tools, by the information input, processing and output of three parts. CNC unit to accept digital information, after the CNC control software and logic circuit for decoding, interpolation, logic processing, will be a variety of instruction information output to the servo system, the servo system to drive the implementation of the parts for the feed motion.   Second, the servo system. By the driver, drive motor, and with the machine tool on the implementation of the components and mechanical drive components of the CNC machine feed system. Its role is to convert the pulse signal from the CNC device into the movement of the moving parts of the machine tool.   Third, the position feedback system. Servo motor feedback of the angular displacement, CNC machine tool actuator (table) displacement feedback. Including grating, rotary encoder, laser rangefinder, magnetic scale, etc.   Fourth, the mechanical components of the machine tool. CNC machine tool mechanical components are similar to the composition of ordinary machine tools, but the transmission structure requirements are more simple, in terms of accuracy, rigidity, seismic requirements, and its transmission and speed change system is more convenient to achieve automated expansion. CNC machine tool work steps: divided into the preparation stage and programming stage   Preparation stage: According to the drawing of the processed part, determine the relevant processing data, and select the relevant other auxiliary information according to the processing process, tool type, etc.   Programming phase: according to the machining process information, write the CNC machining program and fill in the program sheet.

In the mechanical processing operators to follow the operating rules of mechanical amount of processing, then in the development of parts of the mechanical processing process to how to operate correctly? The following is my introduction to the development of parts of the machining process route. 1、First of all, according to the processing accuracy requirements and processing surface roughness of each surface to choose the appropriate processing method.   2, according to the coarse and fine reference requirements to reasonably select the positioning reference of each process.   3, on the basis of the analysis of the part, divided into a good rough and fine machining, and determine the concentration of each process to reasonably arrange the processing sequence of each surface, so as to develop the machining process route of the part.   4, determine the machining allowance of each process and the size of each process and its tolerance. 5, in the premise of ensuring quality and considering the economy, choose the appropriate machine tools and tools, clamps, measurement and cutting tools.   6、Determine the technical requirements and inspection methods of each main Dongxu.   7, in order to ensure the rationality of production and the balance of the rhythm, to choose the appropriate cutting volume and time quota, and not arbitrarily change.   8、Operators fill out the process documents as required.

Box-type parts said to be typical parts of mechanical parts, that today I want to box-type parts as a representative to analyze the parts of the machining process. We know like gear transmission box body, transmission box body, lathe bed box body are the basic parts of the machine, the machine parts of the shaft, bearings, sets and gears and other parts each keep the correct mutual position, and in accordance with the pre-designed transmission relationship so that they coordinate mutual movement, combined into a whole. Box requires processing of many surfaces, each surface processing requirements are different, some of the requirements for high precision, such as the spindle hole, so the box of its machining accuracy has become a key issue in the process, in view of this, in the parts processing also pay attention to the following points:.   1, roughing and finishing stages to be separated   We also mentioned above that the box body to be processed on the surface of many, precision requirements are different, so in the operation to separate the rough and fine machining, and can not rough machining immediately after the fine machining, because this will easily lead to box body deformation, and ultimately affect the accuracy.   2, should be in accordance with the first face after the hole processing order   First processing plane, not only to remove the surface of the rough unevenness and surface sand trap, more importantly, in the processing of the distribution of the hole in the plane, scribing, find a convenient, and when the boring tool to start boring, will not be due to the unevenness of the end surface and the impact vibration, damage to the tool, therefore, it is generally best to first processing plane. 3、Arrange the appropriate heat treatment process   Casting box structure is complex, uneven wall thickness, inconsistent cooling rate during casting, easy to produce internal stress, and the surface is hard, therefore, after casting should be reasonably arranged sandblasting, tempering people.   4, process concentration or decentralized decision   Box roughing and finishing stages are separated in line with the principle of process dispersion, but in the middle and small batch production, in order to reduce the number of machine tools and fixtures used, as well as reduce the number of handling and installation of the box, the roughing and finishing stages can be relatively concentrated, as far as possible on the same machine tool.

CNC lathe machining is widely used, including manufacturing, aviation, medical industry and so on. Because compared to ordinary lathes, CNC lathes have incomparable advantages. 1、Compared with ordinary lathe, the rigidity of CNC lathe is high. In order to match the high precision of CNC lathe with CNC system, the rigidity requirement of CNC lathe must be very high in order to achieve the high precision processing requirements.   2、The spindle of ordinary lathe is variable speed through motor, belt and gear vice mechanism, while the CNC machine tool is completed by two servo motors driving movement in horizontal and vertical directions respectively, so relatively speaking, it does not use traditional parts such as hanging wheel and clutch, which greatly shortens the transmission chain.   3. Compared with ordinary lathe, it is easier to drag because its table movement adopts ball screw vice, which has little friction, so it moves lightly. The supporting special bearings at both ends of the screw are with larger pressure angle than ordinary bearings. The lubrication part of   CNC lathe machining adopts oil mist automatic lubrication, and all these measures make CNC lathe machining move lightly. CNC machining has many advantages.   1、It can ensure the high precision of processing and guarantee the high quality of processing.   2、Automated operation reduces manual labor intensity and improves work efficiency.   3、Automated operation, as long as the operation requirements, do not need skilled machine operators.

CNC lathe feed processing route is the turning tool from the fixed home point of the machine tool from the beginning of the movement, until the return to the home point and end of the processing program after the path. Including the path of cutting processing, cutting tool cutting in and out and other non-cutting empty stroke path. The feed route for finishing is basically in the order of the contour of the part, so the focus of the work to determine the feed route is to determine the feed route for finishing and empty strokes. So what principles should the operator follow in CNC lathe machining? The following principles of finishing machining are introduced by me. 1、Ensure the accuracy of the machined workpiece and the roughness of the surface.   2、Reduce the empty travel time in the feed route to make the shortest machining route, so as to improve the machining efficiency.   3、Simplify the workload of numerical calculation as much as possible and simplify the machining procedure.   4、For some reused programs, subroutines should be used as much as possible.

The unique tool magazine of CNC machining center can realize the function of automatic tool change and spindle orientation. Compared with the general machine tool cost is higher, of course, the processing accuracy and efficiency is also higher. So it is important to choose the right machining center, so as to ensure that the CNC machining center to play the maximum benefit. So for companies to choose the machining center model is also to be quite careful, so what specifically to pay attention to? I will answer the following questions for you. First, the selection procedure should be reasonable, the premise is to have a comprehensive understanding of the machining center, including its performance, characteristics, type, the main parameters applicable range, etc. Only on the basis of a full understanding of the following procedures can be launched.   Second, choose the right type. Select the type of CNC machining process, processing objects, scope, price and other factors should be taken into account. For example, single-sided processing of the workpiece, such as a variety of plate parts, etc., should choose vertical machining work center; more than two sides of the processing of the workpiece or in the surrounding radially radiating row of holes, surface processing, should choose horizontal processing; complex surface processing, such as the guide wheel, the engine on the whole impeller, etc., you can choose five-axis machining center; for the workpiece of high precision requirements, the use of bedroom machining center; the When the size of the larger workpiece for processing, such as the machine bed, column, etc., you can choose the gantry type machining center. Of course the above methods are only for reference, and the final decision should be made under the conditions of process requirements and financial balance.

CNC machining center in the process of high-speed machining, to maintain the smoothness of the load throughout the cutting process, to avoid sudden changes in direction, and also to avoid sudden changes in direction when reducing the amount of feed or tool stop. So what strategies should be followed during CNC machining? The following is introduced by me. When the tool path is determined, the CNC machining center should be dominated by smooth milling during high-speed machining to reduce tool wear and improve machining accuracy. According to the principle of shallow cutting and small layer depth of layering, a reasonable layering route is used to achieve the rationality of machining and smoothness of load. In the corner should increase the circular arc walking tool, to prevent the corner speed vector direction of the sudden change, to avoid sharp changes in the tool load.   In the CNC machining center plane two-way cutting processing, can be in the adjacent two rows of tool trajectory between the additional arc transfer, in order to form a smooth lateral shift. In the space two-way cutting processing, you can use the space arc transfer, space inside the arc transfer, space outside the arc transfer and "golf" type transition transfer and other forms of extended transition, which not only ensures the smoothness of the tool trajectory, but also effectively avoid the phenomenon of turning hard bend between the two lines, this transfer method is commonly used in a variety of Curved surface high-speed milling. In order to avoid the CNC machining center in the shape of the contour of the normal direct feed and retreat, should be used spiral, arc and diagonal way into and out of the tool, to ensure smooth into and out of the tool, the steep wall surface and non-steep wall surface finishing, in order to prevent sharp changes in cutting load, CNC machining center to apply different methods of steep wall surface and non-steep wall surface separate processing, can improve the cutting speed, while making the roughness of the surface of the part uniform.

We know that CNC machining surface geometry characteristics include several aspects of surface roughness, waviness, and machining texture. Among them, surface roughness is the basic unit that constitutes the geometric characteristics of the machined surface. Then when processing the surface of the workpiece with metal cutting tools, the surface roughness is affected by what factors? The following I will introduce to you. When machining the surface of the workpiece with metal cutting tools, the surface roughness is mainly affected by the role and influence of three factors: geometric factors, physical factors and CNC machining process factors.   (1) Geometric factors   From the geometric point of view, the shape and geometric angle of the tool, especially the radius of the tool tip arc, the main offset angle, the secondary offset angle and the amount of feed in the cutting dosage have a greater impact on the surface roughness. (2) Physical factors   Considering the physical substance of the cutting process, the cutting edge rounding of the tool and the extrusion and friction behind make the metal material plastic deformation, which seriously deteriorates the surface roughness. In the CNC lathe processing plastic materials and the formation of ribbon chips, the chip accumulation tumor with high hardness is easily formed on the front tool face. It can replace the front tool face and cutting edge for cutting, so that the geometric angle of the tool and the back eat tool amount are changed. The profile of the chipformer is very irregular, thus causing the surface of the workpiece to have tool marks of varying depth and width. Some of them are embedded in the workpiece surface, which increases the surface roughness. The vibration during the cutting process increases the value of the surface roughness parameter of the workpiece.   (3) Process factors   From the perspective of the process to consider its impact on the surface roughness of hardware parts processing, mainly with the cutting tool-related factors, factors related to the material of the workpiece and factors related to CNC machining conditions.

The first is: tool fixation, mainly for machining unformed workpieces in rotation. The second type is: workpiece fixed, by the high speed rotation of the workpiece, the turning tool's horizontal and longitudinal movement for precision machining. Drills, reaming drills, reamers, taps, plate teeth and knurling tools are also available on the lathe for corresponding machining. Lathe is mainly used for processing shafts, discs, sleeves and other workpieces with rotary surfaces, is the most widely used in machinery manufacturing and repair factories in a class of machine tool processing. The reason why CNC machining should have a wide range is that it has great advantages compared to ordinary lathe machining.   1, CNC lathe processing accuracy is high, high stability, so it can ensure the high quality of processing.   2, a high degree of automation, CNC machining is executed by program decoding, which largely reduces the intensity of manual repetitive work.   3, CNC lathe processing parts change, only need to change the CNC program, which greatly reduces the production preparation time.   4、Multi-coordinate linkage can be carried out, which can process parts with complex shapes.   5, CNC lathe for the operator's quality requirements are also high.