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

The common types of wear in precision parts processing plant mainly include running wear, hard grain wear, surface fatigue wear, heat-like wear, phase change wear and hydrodynamic wear.   Run-in wear is the wear of machinery under normal load, speed and lubrication conditions, this kind of wear is generally slow to develop, the short-term impact on the quality of processing is not significant. Hard particle wear is due to the parts themselves dropped abrasive particles or by the outside world into the machine tool hard particles, mixed into the processing area, subject to mechanical cutting or grinding, causing damage to the parts, which is more serious impact on the quality of machining.   Precision parts processing plant surface fatigue wear is machinery under the action of alternating load, produced a tiny crack or class point-like crater, thus causing damage to the parts. This type of wear is usually closely related to the size of the pressure, load characteristics, machine parts materials, size and other factors. Heat-like wear is the parts in the friction process generated by the heat on the parts, so that the parts have tempering softening, scorching creasing and other phenomena. This type of wear usually occurs in the high-speed and high-pressure sliding friction, wear is more destructive, and accompanied by the nature of accidental wear.   Corrosion wear is a chemical effect, that is, chemical corrosion caused by wear. When the parts surface and acid, alkali, salt liquid or harmful gas contact, it will be chemical erosion, or parts surface and oxygen combined to generate easy to fall off the hard and brittle metal oxides and make parts wear.   Phase change wear is parts of long-term work at high temperatures, parts of the surface metal tissue grain heat becomes large, the grain boundary around the oxidation, resulting in small gaps, so that parts fragile, wear resistance decreased, resulting in parts wear.

In the parts processing industry, the most taboo problem is the deformation of parts, once it appears, the consequences will be unimaginable, one affects the economic efficiency of enterprises, the second to cause a series of safety problems, making the enterprise anxious. So what exactly is the cause of the problem of parts deformation? And how to do to improve it? The main points are as follows.   1, the role of internal forces lead to parts processing accuracy change. Skilled workers know that during processing, the parts are tightened by the three jaws of the lathe to ensure that the parts are processed when the force is stable, over time, it will cause the lathe chuck to loosen, making the parts shrink in force, there will be deformation.   2, heat treatment processing is easy to produce deformation. In the processing of some thin and small parts, generally to first heat treatment, this time if the technical staff due to the professional knowledge is not solid, can not well understand the structural properties of these parts, it is easy to make the parts appear bending phenomenon.   3, the role of external forces resulting in parts processing elastic deformation. In the parts processing, will often use the lathe and fixture, when the two are not flat, will appear in the fixed parts when the force is not uniform, that the force is small side will produce deformation. Improvement measures.   One, after the parts are heat-treated and naturally deformed, then trimmed with professional cutting tools to ensure the perfection of the parts.   Second, technical innovation to increase the stiffness of the part.   Technicians need to improve technology, increase innovation, choose the appropriate limit of heat treatment, change the stiffness of the parts, which makes the parts less likely to deformation.

CNC machine tools in the batch processing of precision mechanical parts, especially to pay attention to the accuracy of processing, then precision machinery plus the public should pay attention to what problems? The following three aspects by the editor to introduce to you from the following.   A, batch parts processing accuracy is poor, generally due to the installation and adjustment, the feed dynamic between the axes according to the error is not well adjusted, or due to the use of wear and tear, the machine tool shaft drive chain has changed. Can be re-adjusted and modify the amount of clearance compensation to solve. When the dynamic tracking error is too large and alarm, you can check: whether the servo motor speed is too high. Position detection element is good. Whether the position feedback cable connector is in good contact. Whether the corresponding analog output latch and gain potentiometer are good. The corresponding servo drive device is normal.   Second, the machine tool movement overshoot caused by processing accuracy is not good, may be acceleration and deceleration time is too short, can be appropriate to extend the speed change time. May also be a loose connection between the servo motor and the screw or rigidity is too poor, can be appropriate to reduce the position of the ring gain. Third, the roundness of the two axes linkage exceeds the difference   (1) Axial deformation of the circle   This deformation may be caused by the machinery is not well adjusted. Poor positioning accuracy of the axis or improper compensation of the screw gap can lead to circularity error when over quadrant.   (2) Oblique ellipse error   In this case, the position deviation value of each axis should be checked first. If the deviation is too large, the position ring gain can be adjusted to exclude. Then check whether the interface plate of the resolver or induction synchronizer is well adjusted, and then check whether the mechanical transmission sub-gap is too large and whether the gap compensation is appropriate.

What are the principles that need to be followed for precision parts processing 1, the benchmark first: that is, the first processing datum surface, parts in the machining process, as a positioning datum appearance should first be processed, in order to provide a fine benchmark for the subsequent processes as soon as possible.   2, divided into processing stages: machining quality requirements of the appearance, are divided into processing stages, generally can be divided into roughing, semi-finishing and finishing three stages. Mainly to ensure the quality of processing; conducive to the scientific application of equipment; to facilitate the arrangement of heat treatment processes; as well as to facilitate the discovery of defects in the blank. 3, first surface and then hole: for the box, bracket and connecting rod and other parts should be processed first plane after processing holes. This can be positioned with the plane to process the hole, to ensure the accuracy of the position of the plane and hole, and to bring convenience to the processing of the hole on the plane.   4, finishing process: the main appearance of the finishing process, such as grinding, honing, fine grinding, rolling processing, etc., should be placed at the end of the process route stage. The general principles of the development of precision parts machining process route, precision parts machining process protocols, can be divided into two links.   First of all, the process route of parts processing, and then determine the process size of each process, the equipment and process equipment used, as well as cutting specifications, work quotas.

As we all know, the reason why the processing of precision parts is called precision machining, precisely because its processing procedures and process requirements are very high, the precision requirements of the product is very high, and the precision of the processing of precision parts contains the accuracy of the location, size accuracy, shape accuracy, etc., summarize the following ten factors affecting the precision of precision parts processing. (1) machine tool spindle runout can produce a certain error in the machining accuracy of the parts.   (2) the accuracy of the machine tool guide inaccuracy can also lead to precision parts machining workpiece shape error.   (3) transmission components can also lead to errors in the processing of the workpiece, which is also the most important factor in the production of the workpiece surface error.   (4) tool, fixture type will also have a different degree of impact on the accuracy of the machined workpiece.   (5) In the process of machining and cutting due to changes in the location of the force point will lead to deformation of the system, resulting in differences, which can also lead to different degrees of error in the accuracy of the workpiece. (6) The different size of the cutting force can also cause the accuracy of the workpiece to be affected.   (7) The process system is subject to errors caused by heat deformation. During machining, the process system will produce certain heat deformation under the action of various heat sources.The deformation of the process system by heat often leads to the accuracy of the workpiece being affected.   (8) Deformation of the machine tool due to heat can lead to deformation of the workpiece.   (9) Heat deformation of the tool can have a significant effect on the workpiece.   (10) The workpiece itself is deformed by heat, mainly during the cutting process.

Precision parts processing has many advantages, we have previously shared with you the specific advantages of precision parts processing, the most obvious is that you can achieve the high precision of ordinary processing can not reach, high precision also depends on precision processing equipment and accurate restraint system, and the use of precision mask as an intermediary to achieve the amount of external surface material removed or added to make very fine control, so what are the characteristics of precision parts processing? First. Precision parts cutting processing   Mainly precision turning, mirror grinding and grinding, etc. In the precision turning machine by fine grinding of single crystal diamond turning tool to hold micro-turning, cutting thickness of only about 1 micron, commonly used in the processing of non-ferrous metal materials such as spherical, aspheric and flat reflective mirror and other high-precision, highly polished appearance of the parts. Second, precision parts processing   Precision parts processing accuracy to nanometers, or even finally to the atomic unit (atomic lattice distance of 0.1 to 0.2 nanometers) as the goal, ultra-precision parts cutting and processing methods can no longer adapt, it is necessary to resort to special precision parts processing methods, that is, the application of chemical energy, electrochemical energy, heat or electricity, etc., so that these energies beyond the joint energy between atoms, so as to remove part of the workpiece appearance of inter-atomic adhesion, The method of ultra-precision machining is achieved by applying chemical, electrochemical, thermal or electrical energy, etc., so that these energies exceed the inter-atomic union energy, thus removing part of the inter-atomic adhesion, union or lattice deformation of the workpiece exterior. These processes include mechanochemical polishing, ion sputtering and ion implantation, electron beam exposure, laser beam processing, metal vapor deposition, and molecular beam epitaxy.

Not all materials can be precision machined. Some materials are so hard that they are beyond the range of hardness for machining. Therefore, these materials are not suitable for precision machining. What should I pay attention to when choosing materials in the field of precision machining? The materials used for nc precision machining parts are mainly divided into two categories: metallic materials and non-metallic materials. For metal materials, the hardness is relatively high on behalf of stainless steel and carbon steel, followed by cast iron, again copper, and finally aluminum; and ceramics and plastic processing is classified as non-metallic processing materials.   First, the requirements of the material hardness. In some special cases, the higher the hardness of the material, the better. It is limited to the hardness requirements of the machined parts. The machined material should not be too hard, if it is harder than the machine parts or machine tools can not be machined.   Second, whether the material is suitable, at least one level lower than the mechanical parts and mechanical tools, but also depends on the function of the equipment and parts processing process.   Precision parts processing for product materials have certain requirements, not all materials are suitable for mechanical processing, let's say too soft or too hard material, too soft no processing necessary, too hard will lead to equipment can not be processed on it. Therefore, in the field of mechanical parts processing, the density of the material needs to be understood before processing the parts. If the density is too high, the corresponding hardness will be higher. If the hardness exceeds the hardness of the machine tool, machining is not possible. In this case, the processing will not only damage the parts, but also cause other hazards, such as broken tools, damage to the machine tool, etc. Therefore, in the field of machining, the processing material should be lower than the hardness of the tool, so that the material is suitable for precision machining.

Those who are engaged in precision machining of mechanical parts know that from the beginning of machining to the time of machining, the positioning datum must be selected. So what is the positioning reference? The positioning datum is used to determine the relative position of the workpiece with respect to the surface of the machine and the tool. The data used at the beginning is unprocessed and is called coarse data. The positioning datum used in subsequent processes is the machined surface, which we call the fine datum.   In the machining process design of mechanical parts, how to choose as a datum surface is a very important issue; whether the choice of positioning datum is reasonable will directly affect the processing quality of precision parts and the complexity of the machine tool fixture structure. The role of the boutique benchmark is different, the selection principles of the two are also different.   Rough benchmark selection principles: one is to ensure that each machined surface has sufficient margin, the second is to ensure that the size and location of the unmachined surface in line with the drawing requirements. The selected coarse datum should be easy to position the part, clamping and processing, so that the fixture structure is simple. If you ensure that the workpiece has been machined surface and the position between the unmachined surface is accurate, the unmachined surface should be used as a rough reference. To ensure that the roughing allowance of the important surface is small and uniform, the surface should be selected as the roughing datum. To ensure that the roughing allowance of the important surface is small and uniform, the surface should be selected as the roughing datum. In order to make the machining allowance of multiple precision machining surfaces on the blank more uniform, the rough machining surface should be selected so that the rough machining surface is based on the selected rough machining datum. A rough datum surface with uniform positional error is a rough datum surface. The rough datum surface should be flat, without defects such as sprue, riser or flying edge, to ensure reliable positioning. General rough datum can only be used once, especially the main positioning datum, so as not to produce a large position error. Mechanical parts machining accuracy benchmark selection principle: the selected positioning benchmark should be easy to locate, clamping and processing, and must have sufficient positioning accuracy. Uniform benchmark principle. When the workpiece is positioned with a certain group of fine datum to facilitate the processing of most of the remaining surfaces, the same group of datum should be used for positioning in the processing of these surfaces, which can reduce the design and manufacture of tooling and avoid datum. Conversion errors and increase productivity. Reference overlap principle. When the machined surface of a precision mechanical part needs to ensure the positional accuracy of the end, the design reference should be selected as the positioning reference. When using the reference consistent principle for positioning and the positional accuracy of these surfaces cannot be guaranteed, reference overlap must be used. The principle is the self-referencing principle. When some surface finishing process requires a small and uniform margin, the machined surface itself can be used as a positioning reference for positioning, when the position accuracy requirements are ensured by the prior process.

What are the causes of deformation of precision mechanical parts processing? In the process of machining mechanical parts, in addition to ensuring dimensional accuracy and surface roughness, attention should be paid to the deformation of parts caused by external forces. About the mechanical precision parts machining deformation, first of all, we need to understand the causes of this problem. First, the external force caused by the deformation of the parts; the reasons can be divided into two categories; one is in the process of machining precision mechanical parts, the parts will change the direction of the force under the influence of cutting force; the reason for this change is the lack of rigidity of the parts themselves. The part will be deformed under the influence of the force. The deformation is generally obvious. When squeezed by force, the part will protrude significantly in the direction of the force, resulting in serious deformation, unable to carry out the next step, the part can not reach the intended requirements as it should be, and become substandard products.   Second, the knife cutting process generated by the heat deformation; in the process of precision parts processing, the blade and the blank will have violent surface contact, the contact point will inevitably generate high temperature. If appropriate cooling methods are not used, coupled with differences in tool heat dissipation, increased wear, coupled with poor material heat resistance and high temperature at the point of contact, deformation will occur during the processing of precision mechanical parts, so that the product can not reach the required shape. Third, parts processing in the clamping caused by deformation; parts need to be clamped before processing, which is also a major cause of parts deformation. When clamping parts, you should choose the appropriate clamping point and clamping force. The number of clamping points and support points of the part should be the same. If there are multiple clamping points on a part, attention should be paid to the clamping sequence and the clamping strength. Machining is also difficult if not done properly. It is easy to deform.

What are the material parts suitable for mechanical precision parts processing? In the machining industry, machining accuracy often determines the quality of the machined parts, and the machining of CNC precision parts is itself a very demanding machining method. Compared with traditional processing methods, CNC precision parts have better results and many advantages that other processing methods do not have. What are the advantages of CNC precision machining? In today's machining field, the machining of precision parts relies on CNC machining. The processing problem has not been solved, and the processing quality has been effectively improved. According to Ruifeng precision, in the machining industry, processing accuracy often determines the quality of processed parts, CNC precision parts processing itself is a highly demanding processing method. Compared with traditional processing methods, better results are achieved. There are many advantages that other machining methods do not have. What are the advantages of CNC precision parts machining? The following Ruifeng precision to give you a brief introduction to.   With the development of precision CNC machining industry, the sheet metal processing accuracy requirements continue to improve, sheet metal processing in the bending machine also appeared manual bending machine and CNC bending machine. The repetition accuracy of manual bending machine slider is inches, and the repetition positioning accuracy of CNC bending machine is inches. Regarding the precision, the precision of CNC bending machine has been improved by 50 times. In recent years, precision cnc machining technology has been applied. Due to the small cutting force, the machining deformation of the parts can be reduced and it is suitable for thin-walled parts. The chips are removed in a short time, most of the cutting heat is taken away by the chips, the workpiece thermal deformation is small, which is conducive to ensuring the size and shape accuracy of the parts; because high-speed machining can obtain a higher surface quality, greatly reducing the processing cycle, therefore, combined with the characteristics of this thin-walled parts, precision cavity using high-speed precision cnc machining.   This happens because CNC machining has many advantages, not only easy to operate, the processing effect is also very good, because of this. Therefore, the CNC precision parts machining industry is so highly regarded. Do you know the specific advantages of CNC machining? Summarize the advantages of CNC machining, there are four main points: 1, the direct use of engineering plastics. Low material cost, wide range of material selection. 2, stable performance of machinery and equipment, simple operation. 3, the parts can be properly decomposed. 4, especially suitable for large, simple structure of the parts processing. How to operate to improve the machining accuracy of precision parts? First of all, precision parts processing is a kind of mechanical processing, but more precise; higher requirements for the production of machinery and technology. Some machined surfaces of precision parts can be completed by only one installation, but if the program is too long, it is sometimes affected by the continuous working time of the machine tool in the memory. For example, a process cannot be completed in one working time, etc. In addition, too long programs can increase errors and retrieval difficulties, so in cnc precision machining, the program prepared should not be too long and the content of each process should not be too much. Adopt one installation machining as one process. This method is suitable for parts with little processing content, which can be in a state to be checked after processing.   Precision CNC parts processing factory quality is very good, most precision light alloy (aluminum and magnesium alloy, etc.) precision vehicles and bowling machines are processed by this method. Generally use natural single crystal diamond tool, the edge of the radius of the circle is less than micron. After processing with high precision lathe, it can get 1 micron precision and the average height difference is less than micron surface bump, and the coordinate precision can reach 2 micron. CNC precision machining mainly includes precision lathe precision milling and grinding.   CNC machining machine tools have been very common in the field of machining, the application is very wide, is now a large mechanical processing machine tools commonly used in the field of precision machining.   In the machining industry, processing accuracy often determines the quality of the processed parts, CNC precision parts processing itself is a very demanding processing method. Compared with traditional machining methods, CNC precision parts have many advantages that other machining methods do not have. What are the advantages of machining CNC precision parts?   Compared with ordinary lathes, CNC lathes have a certain linear speed cutting function, and the same linear speed can be used to process either turning end faces or outer circles of different diameters. In other words, the value of surface roughness is consistent and relatively small. Generally speaking, the rotational speed of the lathe is constant, and the cutting speed varies according to the diameter. When the material finishing margin and tool angle of the workpiece and tool are constant, the surface roughness depends on the cutting speed and feed rate. As we all know, precision machining requires high precision, high rigidity of precision machining, high manufacturing accuracy and high precision of tool machining.   Strictly speaking, in the professional, large mechanical parts processing and general machining there are able to very fine control of the removal and addition of the amount of material on the outer surface of the intermediary. We know that precision machining has requirements for precision, precision machining with high rigidity and high manufacturing accuracy, and can process parts with requirements for precision. So, what is the material parts suitable for precision machining?2. Material soft and hard moderate, precision mechanical parts processing material is at least lower than the hardness of the lathe turning tool. At the same time to understand the specific technology such as precision mechanical parts processing, have some knowledge and understanding of these technologies, at least some differences and differences, so only to understand the specific differences between them, in order to correctly distinguish between ordinary machining and large-scale machining, so as not to affect the normal processing of machinery, so that the choice of problems.