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

The machined surface quality of precision mechanical parts includes the geometric shape characteristics of the machined surface and the changes in the machined surface materials. In addition to understanding the five stages of precision mechanical parts processing and how to improve the efficiency of precision mechanical parts processing, we should also know that the machined surface of precision mechanical parts actually has different degrees of machining errors such as hardness and cracks, The surface of mechanical parts is difficult to achieve the ideal smooth surface, which will have a great impact on the fitting accuracy, wear resistance, corrosion resistance and fatigue strength of precision mechanical parts, and will affect the service life of mechanical equipment to a certain extent. 1. Affect the fitting accuracy of mechanical parts The large roughness of the machined surface of precision mechanical parts will reduce the fitting accuracy between parts to a certain extent. If there is a large residual stress on the machined surface, the stability of the fitting accuracy between parts will be seriously affected. 2. Affect the wear resistance of mechanical parts The machined surface roughness of precision mechanical parts is large, resulting in the increase of contact surface pressure. The peaks between the surfaces bite, crack and cut off each other, which aggravates the wear of the parts surface. The machined surface of precision mechanical parts is too smooth, the lubricating oil reservoir is not stable, and the contact surface between parts cannot be covered, which is prone to molecular bonding, and also easy to aggravate the wear of the surface of parts. 3. Affect the abrasion resistance of mechanical parts The greater the surface roughness of precision mechanical parts, the easier it is to accumulate abrasive substances. The deeper the valley, the stronger the penetration and corrosion. 4. Influence the fatigue strength of mechanical parts The greater the machined surface roughness of precision mechanical parts, the worse their fatigue damage resistance. Under the action of alternating load, the concave parts of the surface roughness of mechanical parts are easy to cause stress concentration and fatigue cracks. The smaller the roughness of the machined surface, the fewer the defects. The better the fatigue resistance of the mechanical parts. The greater the roughness, the deeper the wrinkles on the surface of the mechanical parts. The smaller the radius of the bottom of the wrinkles, the worse the fatigue resistance. The machined surface quality of precision mechanical parts will have a certain impact on the matching accuracy, wear resistance, corrosion resistance and fatigue strength of mechanical parts. Therefore, when machining precision mechanical parts, the surface roughness of mechanical parts should reach an appropriate level as far as possible, which can better extend the service life of mechanical equipment and reduce the failure repair rate of mechanical equipment.

With the rapid development trend of manufacturing industry, people's production and processing methods are constantly improving. There were very few methods before, but now there are more and more. Precision parts are processed in the same way. What are the types of precision parts processing methods? The production process of precision parts includes turning, milling, planing, grinding, pliers, stamping dies, forging and other methods. Stamping die. The production process of precision hardware processing is divided into project die and continuous die. The project die is also called single stamping die. Some very complex parts need two sets of abrasive tools, while the continuous die splits the appearance of the commodity into many parts in one abrasive tool in the concave mold of the abrasive tool. In this way, a high-speed punch production and processing schedule means a finished product. The high-speed continuous high-speed punch can produce and process 300 or 400 commodities per minute. CNC lathe: CNC lathe for precision parts processing belongs to precision machining mechanical equipment, which can be divided into CNC lathe, automatic lathe, instrument lathe and CNC lathe on computer. The utility model carries out rotary fitness movement after the raw materials are clamped, and the milling cutter carries out axial or radial production and processing. Nowadays, automatic lathes and CNC lathes are used more and more widely. Because these two types of production and processing are all automatic, the precision deviation caused by actual operation of human factors has been reduced to the lowest point, and the production and processing are faster for batch production. Nowadays, the vast majority of CNC lathes on computers are equipped with side rotating CNC blades and reverse rotating CNC blades, which can also be used for cutting production and processing.

In the process of precision mechanical parts processing, the machine is rotating very fast. If a link is found to be missing in the middle of the process, and the machine equipment is suddenly suspended, or the quality of the machined parts may be affected. Therefore, when the parts are precision processed, due to the many and precise processing procedures, there are many details that we cannot ignore in the process of precision mechanical parts processing. The following sections will give you a general introduction. 1. Separate fine and rough machining of parts to avoid affecting precision When the parts need to be precision machined, due to the large cutting amount, the workpiece is subject to large cutting force and clamping force, generating a lot of heat. There is obvious work hardening phenomenon on the machined surface, and there is large internal stress in the workpiece. If rough machining is continued, the precision of the finished parts will be lost due to stress redistribution. For some parts with high machining accuracy, low temperature annealing and aging treatment shall be arranged after rough machining and before finishing to eliminate internal stress. 2. Select appropriate processing machines and equipment Rough machining is mainly to cut off most of the machining allowance, and does not require high machining accuracy. Therefore, rough machining should be carried out on a machine tool with high power and low accuracy, while finishing requires a machine tool with high accuracy. Rough and finish machining are processed on different machine tools, which can not only give full play to the equipment capacity, but also extend the service life of precision machine tools. 3. Heat treatment process is required in the processing route The heat treatment process is arranged as follows: In order to improve the metal cutting performance, such as annealing, normalizing, quenching and tempering, it is generally arranged before processing. In order to eliminate internal stress, such as aging treatment, quenching and tempering treatment, it is generally arranged after rough machining and before finishing. In order to improve the mechanical properties of parts, such as carburizing, quenching, tempering, etc., they are generally arranged after machining. In case of large deformation after heat treatment, the final processing procedure shall be arranged. Details to be paid attention to in precision machining 1. In order to facilitate processing operations, it is necessary to reduce back and forth walking, and reduce or avoid bending and foot stepping of processing personnel. 2. The machined parts shall be positioned accurately to prevent vibration from affecting the production operation and avoid misoperation. 3. The moving direction of the working parts and the moving direction of the working parts of the machine tool shall comply with the regulations and be marked with simple symbols. The structure and layout of handles, hand wheels and buttons shall meet the requirements. 4. The start button shall be installed in an enclosure with a guard ring to prevent accidental contact. The handwheel and handle installed on the shaft rod will rotate with the shaft to hurt people during automatic feeding, so an automatic release device should be installed.

What is fine machining? What kind of processing is fine machinery mainly used for? What are the requirements for information? The machining accuracy is more accurate than that of ordinary machines. Machines that reach or exceed 0.1 μ m are fine machines. Generally, fine machining is completed under strictly controlled environmental conditions by using fine machine tools, fine measuring tools and meters. It can be used for fine fittings in hydraulic and pneumatic servo mechanisms of aerospace industry, frames and shells of gyroscopes, air and liquid floating bearing components and floats. The data on fine machining can be divided into two categories: metal data and nonmetal data. Do you have any request for information on fine machining? Not all materials are suitable for processing with fine parts. As for metal materials, the hardness is in the order of stainless steel, cast iron, copper and aluminum. The processing of ceramics and plastics belongs to the processing of non-metallic materials. It is limited to the hardness request of processing parts. In some places, the higher the hardness value, the better. However, the processing data cannot be too hard, or the processing cannot be stopped. Therefore, it is necessary to select reasonable materials for the parts according to the role of the processed devices. In ordinary places, it is better to compare the soft and hard materials. Before stopping fine machining, you must pay attention to the density (hardness) of the selected materials. If the hardness has exceeded the hardness of the machine parts (lathe tools), not only the parts cannot be machined, but also the parts may be damaged or risk may be formed. For example, in the past, there have been incidents of turning tools flying in and injuring people. Therefore, for mechanical processing, the material must be lower than the hardness of the machine tool, so that it can be processed. Fine machining mainly includes fine turning, fine boring, fine milling, fine grinding and grinding. Effect: the boundary line or feature dimension tolerance of the part is below micrometer; Geometric shape and mutual position accuracy reach micron or angular second level; The surface micro unevenness is less than 0.1 μ m; Mutual fittings can meet the requirements of combination force and accurate mechanical or other physical characteristics.

How to improve the quality of precision machining? It is a link to find out the main factors (original errors) that cause machining errors, but how to take corresponding technological measures to control or reduce the impact of these factors? Now let's find out how to effectively improve the quality of precision machining in four ways: 1、 Error compensation method This method is to artificially create a new original error, which can offset the original error inherent in the original process system, so as to reduce the processing error and processing accuracy. 2、 Error transfer method This method essentially transfers the geometric error, stress deformation and thermal deformation of the process system to the direction that does not affect the machining accuracy. For example, for a multi station process with indexing or indexing or a process using an indexing tool holder, the indexing and conversion errors will directly affect the machining accuracy of the relevant surfaces of the parts. 3、 Error averaging method In this method, surfaces that have intimate connection with each other are mutually corrected, or processed according to each other. It can make those local large errors affect the whole machining surface more evenly, so that the machining errors transmitted to the workpiece surface are more symmetrical, so that the machining accuracy response of the workpiece is greatly improved. 4、 Direct error reduction method This method is a basic method widely used in production. This method is to find out the main original error factors that affect the machining accuracy, and then try to eliminate or reduce them directly. For example, the turning of slender shafts will cause bending deformation due to the influence of force and heat. Now, the "big straight cutter reverse cutting method" is adopted to basically eliminate the bending caused by the cutting force. With the help of the spring center, the harm of thermal elongation can be further eliminated.

The advantage of non-standard precision parts machining is that non-standard parts machining center is developed from CNC milling machine. It is very different from the CNC milling machine in that the machining center has the talent to automatically exchange processing tools. By installing tools with different purposes on the tool magazine, the machining tools on the spindle can be changed through the automatic tool change device in a single clamping process to achieve multiple processing effects. Non standard precision parts processing equipment is suitable for large batch, high precision and complex processing, especially for arc and taper processing. The advantages of non-standard parts processing are small. Non standard parts processing ranges from one digit to three digits. They are directly processed through simple molds and soft molds. Non standard parts are generally processed by turning, milling, planing, grinding, pliers and other common machining processes, as well as cutting, drawing, drilling, tapping, etc. of fitters. Representative industries include aviation, aerospace industry, shipbuilding industry, equipment machinery industry, machine tool industry, etc. The typical example of mass production is the automobile industry, while the trial production of new models and engines in the automobile industry and the mold industry that is important for mass production still belong to single small batch production. The advantage of non-standard parts processing is small batch production, which can greatly save time and materials, and speed up the cycle of product launch. Small batch production is inextricably linked with prototype mold. Prototype mold is the condition for processing small non-standard parts, and the processing of small non-standard parts is based on the prototype mold.

What are the advantages and disadvantages of CNC machining? CNC machining has the following advantages: ① The number of tooling is greatly reduced, and complex tooling is not required for processing parts with complex shapes. If you want to change the shape and size of parts, you only need to modify the part processing program, which is applicable to the development and modification of new products. ② The machining quality is stable, the machining accuracy is high, and the repetition accuracy is high, which meets the machining requirements of aircraft. ③ The production efficiency is high in the case of multiple varieties and small batch production, which can reduce the time for production preparation, machine tool adjustment and process inspection, and reduce the cutting time due to the use of the best cutting amount. ④ It can be used to machine complex surfaces that are difficult to be processed by conventional methods, or even some processing parts that cannot be observed. CNC, also known as computer gong, CNCCH or CNC machine tool, is actually a name from Hong Kong. Later, it was introduced into the Pearl River Delta, which is actually a CNC milling machine. It is a new processing technology. Its main work is to prepare processing programs, that is, to convert the original manual work into computer programming. Of course, experience in manual processing is required. CNC, also known as machining center, has a wide range of applications, not limited to furniture production. Therefore, it is worth learning from the experience of various industries in the use of CNC. Here are the following points: 1. The speed of white steel knife shall not be too fast. 2. The copper workers should use less white steel knives for rough cutting and more flying knives or alloy knives. 3. If the workpiece is too high, it should be cut with knives of different lengths in layers. 4. After roughening with a big knife, use a small knife to remove the surplus material, and smooth the knife only when the surplus is consistent. 5. The plane shall be processed with flat bottom cutter and less with ball cutter to reduce processing time. 6. When the copper worker cleans the corner, first check the size of R on the corner, and then determine the size of the ball knife. 8. If the slope is an integer, the slope cutter shall be used for processing, such as pipe position. 9. Before each process, think about the remaining allowance after the previous process to avoid empty cutter or excessive machining. 10. Try to follow a simple cutting path, such as contour, grooving, single side, and less surrounding height. 11. When walking WCUT, those who can walk FINISH should not walk ROUGH. 12. When the profile light knife is used, rough polishing shall be carried out first, and then fine polishing. When the workpiece is too high, the edge shall be polished first, and then the bottom shall be polished.

How to ensure the dimension when CNC machine tools are processing aluminum? First of all, on the premise of aluminum, the following aspects should be considered: Force majeure: 1. Stability of the machine tool itself. If it is not a new machine tool or the machine tool has undergone a lot of processing without debugging, the size error caused by the machine tool itself will occur. The error of the machine tool itself is caused by the following factors: Mechanical: a. Looseness between servo motor and lead screw. b. The ball screw bearing or nut is worn. c. Insufficient lubrication between lead screw and nut. Electrical: a. Servo motor fault. b. There is dirt inside the grating ruler. c. Servo amplifier fault. The system parameters can be recovered by PMC, so they are omitted. 2. The workpiece is deformed after cooling. This is basically unavoidable. During processing, pay attention to the use of coolant as much as possible, and during in position measurement, pay attention to the deformation of the workpiece after cooling.  Avoidable factors: 1. Processing technology In fact, most of the actual processing errors are caused by unreasonable processing technology. On the basis of ensuring the basic processing technology (such as "roughing first and then finishing, face first and then hole, large face first and then small face" in CNC milling, or "reducing the number of clamping times and using modular fixtures as much as possible" in the use of fixtures), try to reduce the processing errors caused by iron filings on aluminum parts, because aluminum parts are very soft, The iron scraps removed will easily cause machining errors for aluminum parts. For example, use the G83 command as much as possible to drill deep holes so that iron filings can be discharged, instead of the G73 command. 2. Three elements of cutting: cutting speed vc, feed rate f, cutting depth ap and tool compensation It is hard to say in detail in this respect. To put it simply, on the premise of ensuring the processing quality and tool wear, adjust the parameters to give full play to the cutting performance of the tool, so that the cutting efficiency is the highest and the processing cost is the lowest. In CNC lathes, there are elements such as cutter head wear compensation. 3. Numerical calculation in manual programming and automatic programming In manual programming, calculation errors are also common, but now most production is automatic programming. 4. Tool setting Inaccurate tool setting is also a factor that causes dimensional error. Try to choose a good edge finder. It would be better if the machine tool has an automatic tool setting device. If there is no edge finder for trial cutting, this is the operating experience.

How to Select Aluminum Profile CNC Machining Center Correctly The profile machining center is an active composite machining center integrating milling, drilling, tapping, chamfering, and rigid tapping. It has a large stroke, can process long profiles, and can replace the operation of gantry machining center. It has the characteristics of high cost performance and high power. It is suitable for processing various lengths of steel, copper, aluminum profiles and other metal processing, equipped with active chip removal machine. Due to the uniqueness of processing objectives, aluminum profile machining centers differ greatly from general machining centers in terms of structure layout, skill parameters and NC system planning. Compared with the processing centers of the same industry, the aluminum profile processing center has the following advantages: 1. High spindle speed The maximum spindle speed of a universal machining center is generally below 8000 rpm; However, the maximum spindle speed of Nantong Vertical and Horizontal Aluminum Profile Machining Center should reach or exceed 24,000 rpm Due to the high speed, the spindle imported from Italy, high-speed ceramic bearing and closed liquid thermostatic control system are selected to ensure continuous 24-hour high-speed operation. The coolant system is divided into pouring cooling and spray cooling The latter is attributed to the more advanced concept of quasi dry cutting and micro smoothing system (MQL), which has high cooling power and low coolant consumption, and is particularly suitable for aluminum profile processing. Nantong Zongzong uses spray cooling system to cool tools. 2. Large transverse travel is the characteristic of long and thin aluminum profile parts, and the worktable of aluminum profile machining center is mostly narrow and long. The working platform is 400mm wide; The worktable with a length of 6500mm or longer is processed with typical 6m profiles. The worktable is equipped with pneumatic fixture, and the active positioning and clamping system is selected, which can quickly clamp the workpieces. It can be processed with double operation areas, greatly saving the time for loading and unloading. T-shaped groove is selected for the worktable. In recent years, with the expansion of the scope of use of industrial aluminum, especially the application of aluminum alloy materials in the fields of track transportation, aerospace, automobile and ship industry, the technical requirements of industrial aluminum processing profession are becoming higher and higher. Only by vigorously connecting with the industrial aluminum processing category, can we develop more types of aluminum processing centers for occupations such as traffic, automobile industry, decoration and building materials. In addition, in the process of practical application, it is necessary to accumulate a lot of data and materials for the industrial aluminum processing profession. Nantong Zongzong's mission has always been to constantly research and develop new ideas, satisfy customers' needs, create value for customers, and provide personalized treatment plans for industrial aluminum processing and other enterprises.

What are the advantages of CNC machining center over ordinary CNC machine tools 1、 CNC machining center has the following advantages over ordinary CNC machine tools 1. Reduce the number of machine tools to facilitate management. For parts with many processing procedures, only one CNC machining center can complete all processing. 2. Since the workpiece can complete all the processing procedures only with one clamping, it can avoid the positioning error caused by multiple clamping of the workpiece in different CNC machine tools, and the accuracy of the CNC machining center can be relied on to ensure the quality of the processed workpiece. 3. Because only one CNC machining center is needed to complete the work of several ordinary CNC machines, the process is centralized, reducing the processing time and improving the production efficiency. 2、 Specific differences between CNC machining centers and ordinary CNC machine tools The biggest difference between CNC machining center and ordinary CNC machine tools is that CNC machining center has a tool magazine and tool changing device more than CNC machine tools. CNC machining center further improves the automation degree and production efficiency of ordinary CNC machine tools. The most specific difference between CNC machining centers and general CNC machine tools is that CNC machining centers only need to be clamped once when machining workpieces, and CNC system devices can control the machine tool to automatically replace tools, and automatically perform multiple processes such as milling, boring, drilling, reaming and tapping on each machining surface of workpieces, especially suitable for machining box type parts. However, it is very troublesome to replace the cutter with an ordinary CNC machine tool, which requires manual replacement. Therefore, when processing workpieces with more processes, several CNC machines are often required to cooperate. CNC machining center has many advantages, so it is an indispensable and important CNC mechanical equipment in the production of CNC machine tools. For example, the current five axis machining center can hardly be replaced by other CNC equipment. The five axis machining center can be used to process complex spatial curved surface parts, such as propeller, aircraft curved surface parts, etc. It is widely used as one of the most important mechanical equipment in all high-tech industries.