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

Machining parts on CNC lathe should be divided into processes according to the principle of process concentration, and most or even all surfaces should be finished under one clamping as far as possible. According to different structure shapes, usually choose external circle, end face or internal hole, end face clamping, and strive to unify the design reference, process reference and programming origin. In mass production, the following methods are commonly used to divide the process. 1, According to the part processing surface division process   That is, the completion of the same part of the surface process for a process, for the processing of multiple and complex surface parts, according to its structural characteristics (such as internal shape, shape, surface and plane, etc.) into multiple processes.   The surface requiring high positional accuracy will be completed in one clamping, so as not to affect the positional accuracy of the error generated by multiple positioning clamping. As shown in Figure 1, in accordance with the process characteristics of the part, the outer and inner contours of the rough and finish machining in a process to reduce the number of clamping, which is conducive to ensuring coaxiality.   2、Dividing the process by roughing and finishing   That is, the part of the process completed in rough machining is a process, and the part of the process completed in finishing machining is a process. For the parts with large margin and high processing accuracy requirements, roughing and finishing should be separated and divided into two or more processes. Rough turning will be arranged in the lower precision, higher power CNC machine tools to carry out, the finish turning will be arranged in the higher precision CNC machine tools to complete.   This division method is suitable for parts with large deformation after machining, which require separate rough and finish machining, such as parts with blanks of castings, welded parts or forgings.   Dividing the process according to the type of tool used   3、Dividing the process according to the type of tool used   The same tool to complete the part of the process for a process, this method is suitable for the workpiece surface to be machined more, machine tools work continuously for a long time, the preparation of processing procedures and check the difficulty of the situation.   4, according to the number of times the installation process   A part of the process to complete the installation for a process. This method is suitable for workpieces with little processing content, the processing is completed to reach the state of pending inspection. After serious and careful analysis of the part diagram, the following basic principles should be followed to develop the machining plan - coarse first, then fine, near then far, inside and outside cross, the least number of program segments, and the shortest tool route.   (1) Coarse first and then fine   It means that the machining accuracy is gradually improved according to the sequence of rough turning and half finishing turning. In order to improve production efficiency and ensure the quality of finishing parts, in the cutting process, the roughing process should be arranged first, in a shorter period of time, most of the machining allowance before finishing is removed, while trying to ensure that the finishing allowance is uniform.   (2) Near first and then far   The far and near mentioned here are according to the distance of the machining part relative to the tooling point. In general, especially in rough machining, it is usually arranged that the part near to the tool point will be machined first, and the part far from the tool point will be machined later, in order to shorten the tool movement distance and reduce the empty travel time.   (3) Internal and external crossover   For both the inner surface (inner cavity) and the outer surface of the parts to be machined, the processing sequence should be arranged so that rough machining of the inner and outer surfaces is carried out first, followed by finishing machining of the inner and outer surfaces.

Due to the special characteristics of aluminum, no matter what kind of machine tool is used for machining, the efficiency, life and gloss of the workpiece are often not satisfactory. Therefore, when processing aluminum, how to choose the right tool and processing technology has become a concern. Let's first understand the processing characteristics of aluminum and aluminum alloy: aluminum has low strength, low hardness and plasticity, which is suitable for plastic forming processing, but the tendency of deformation and reinforcement during cutting is large, easy to stick to the tool, and it is difficult to process a bright and clean surface. Compared with pure aluminum, aluminum alloy has improved a lot in strength and hardness, but compared with steel, it has low strength and hardness, small cutting force and good thermal conductivity. Because of the soft quality and plasticity of aluminum alloy, it is easy to stick to the tool when cutting and form chip tumor on the tool, and may produce melt welding phenomenon on the tool edge when cutting at high speed, which makes the tool lose cutting ability and affects the machining accuracy and surface finish. In addition, the coefficient of thermal expansion of aluminum alloy is large, and the cutting heat is likely to cause thermal deformation of the workpiece and reduce the machining accuracy.

Machining methods for non-standard precision mechanical parts. Non-standard precision parts processing requirements for precision is extremely high, to achieve ultra-lubricated processing appearance and very high machining accuracy, that naturally the tool by a very high demand, if the tool wear, then the processing surface quality will be reduced. And in the ultra-precision cutting, and general cutting rules are not the same, the cutting speed is not subject to the standard life of the tool constraints.   Non-standard precision parts processing generally choose the smallest speed, which is based on the ultra-precision machine tool transmission characteristics and cutting characteristics, because the minimum speed can make the appearance of the smallest roughness, thus ensuring the highest quality of processing - high. Of course, the premise is to ensure the quality of the machine tool can drive high cutting speed to ensure the efficiency of processing. Non-standard precision parts processing should be based on the cutting tool, cutting speed, depth of cut and feed rate parameters such as selection, according to past experience we know, in the processing of plastic materials, if the selection of a larger front angle of the tool can be useful to press the composition of the chip tumor, which is the tool front angle increases, the cutting force is reduced, cutting deformation is small, the tool and chip contact length becomes shorter, reducing the basis of the chip tumor. Ltd. is a professional manufacturer of metal non-standard parts, ￠ 0.5 - ￠ 20mm stainless steel, titanium, aluminum and other metal precision parts manufacturing has many years of technical precipitation.

CNC machines consist of programs, input/output devices, CNC units, servo systems, position feedback systems, and machine bodies. (1) CNC unit   CNC unit is the core of CNC machine tools, CNC unit consists of information input, processing and output of three parts.   CNC unit accepts digital information, after the control software and logic circuit of the CNC device for decoding, interpolation, logic processing, will be a variety of instruction information output to the servo system, the servo system to drive the executive parts for the feed movement.   Others are the main moving parts of the variable speed, reversing and start-stop signal; selection and exchange of tools tool command signal, cooling, lubrication start-stop, workpiece and machine parts loosening, clamping, indexing table rotation and other auxiliary command signal.   (2) 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 tool 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. For stepper motors, each pulse signal makes the motor turn an angle, which in turn drives the machine tool moving parts to move a small distance. Each feed motion of the executive components have the corresponding servo drive system, the performance of the entire machine depends mainly on the servo system. (3) 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.   Feedback device to detect the results into electrical signals back to the CNC device, through comparison, calculate the deviation between the actual position and the command position, and issue deviation instructions to control the feed movement of the executive components.   (4) mechanical components of the machine tool   For the machining center class of CNC machine tools, and storage tool magazine, tool exchange robot and other components, CNC machine tool mechanical components and ordinary machine tools are similar, but the transmission structure requirements are more simple, in terms of accuracy, rigidity, vibration resistance and other requirements, and its transmission and speed change system is more convenient to achieve automation expansion.

The operation of machinery and equipment is simple and complex. Simple because the pre-programmed compiled and executed, complex because the need for professional rigorous operation, mechanical equipment testing and maintenance is also the same. The following to introduce you to the general knowledge of mechanical equipment testing and maintenance.   1、Through the training of employees, make them familiar with the basic operation techniques of equipment maintenance and equipment use to avoid equipment failure or damage caused by improper operation;   2、Training specialized technical personnel, familiar with the construction of equipment and fault diagnosis, troubleshooting and overhaul techniques;   3, collect and summarize the experience of equipment management to improve the efficiency of the use and management of equipment.   For preventive equipment overhaul and maintenance, the purpose is to minimize the cost of equipment maintenance to maximize the utility of the equipment, so it is essentially a matter of choosing the best maintenance cost and benefit-price ratio. This is both a management problem and an optimization problem. This problem is more concentrated in the maintenance and maintenance schedule of the equipment. In the process of using the equipment, it is affected by the temperature and humidity of the working environment, the continuous running time, the service life of the equipment, the material of the equipment, etc. This requires the maintenance personnel to analyze the health condition of the equipment operation through the situation reflected in the actual use of machinery and equipment, so as to make a reasonable schedule of daily maintenance and downtime repair of the equipment in due time. The effect of this should be firstly to avoid unnecessary downtime, and secondly to achieve the daily maintenance of the equipment without affecting the normal operation of the equipment as far as possible, and to deal with the abnormal conditions found in time.

Precision parts processing is a complex and rigorous process, is a combination of each step of the processing process, so what are the specific points of the production of precision parts processing? The following to introduce you to. The production process of the machine is the whole process of making the product from raw materials (or semi-finished products). For the production of machines including the transport and preservation of raw materials, production preparation, manufacturing of blanks, parts processing and heat treatment, product assembly, and commissioning, painting and packaging. Modern enterprises use the principles and methods of system engineering to organize and guide production, and view the production process as a production system with inputs and outputs.   In the production process, any process that changes the shape, size, location and nature of the production object to make it a finished or semi-finished product is called a process. It is the main part of the production process. Processes can be divided into casting, forging, stamping, welding, machining, assembly and other processes, machinery manufacturing process generally refers to the sum of the mechanical processing process of parts and machine assembly process, other processes are called auxiliary processes, such as transportation, storage, power supply, equipment maintenance, etc.. Processes are composed of one or several sequential processes, a process consists of a number of work steps. Precision parts machining process process is the basic unit of the composition of the machining process. The so-called process refers to a (or a group of) workers, in a machine tool (or a workplace), on the same workpiece (or at the same time on several workpieces) by the continuous completion of that part of the process. The main characteristic of a process is not to change the processing object, equipment and operator, and the content of the process is completed continuously.

CNC lathe machining is a small part of machining, so what forms of machining are there in CNC lathe machining? One: Turning tool fixation, mainly for machining unformed workpieces in rotation.   The second is: workpiece fixation, through the high-speed rotation of the workpiece, the turning tool's horizontal and vertical movement for precision machining. In the lathe also available drill, reaming drill, reamer, tap, plate and knurling tool for corresponding processing. 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.

With the development of industrialization, the metalworking industry has also developed rapidly, and various new materials and new process innovations have emerged, but to ensure and improve the processing quality and efficiency of products, it has become an important link in choosing the right metal cutting fluid and minimizing the pollution to the environment. But the choice of metal cutting fluid for different machining tools is also a difficult choice. First, the types of cutting fluid commonly used in CNC machine tools   In order to adapt to different processing occasions and process requirements, metal cutting fluid types are also diverse, which are mainly divided into two categories according to the chemical composition and state, namely water-based cutting fluid and oil-based cutting fluid.   1、Water-based cutting fluids are cutting fluids that need to be diluted with water in advance when they are used. Antirust emulsions, antirust lubricant emulsions, extreme pressure emulsions and microemulsions all belong to this broad category. The role of water-based cutting fluid is usually based on cooling and cleaning, the effect of lubrication is not obvious.   2, oil-based cutting fluid refers to the use of cutting fluids that do not require water for dilution. Pure mineral oil, fatty oil, oil additives, mineral oil, non-active extreme pressure cutting oil and active extreme pressure cutting oil all belong to this type. Contrary to water-based cutting fluids, oil-based cutting fluids have a more obvious lubricating effect, while the cooling and cleaning ability is poor. Second, the choice of cutting fluid for different processing tools   Different processing tools, due to their different tool performance, suitable for processing the material characteristics also differ, therefore suitable for the use of different types of cutting fluid   1, for high-speed steel material tools, in the medium and low-speed cutting, heat generation is not large, suitable for the use of oil-based cutting fluid or emulsion. In high speed cutting, due to the high heat generation, the use of water-based cutting fluid can play a good cooling effect. At this time, if you use oil-based cutting fluid, it will produce a lot of oil mist, which will pollute the environment and easily cause burns on the workpiece, affecting the machining quality and the service life of the tool. In addition, it is better to use extreme pressure aqueous solution or extreme pressure emulsion during rough machining, while extreme pressure emulsion or extreme pressure cutting oil is more suitable during finishing machining.   High-speed steels use medium-speed cutting operations at a rate of about 70 m/m. High-speed steels are iron alloys containing elements such as tungsten and chromium to increase their hardness and wear resistance; even so, their hardness and wear resistance qualities are reduced to unacceptable levels by temperatures above 600°C. However, water-soluble cutting oils can be used. However, water-soluble cutting oil can be used to keep its operating temperature below 600℃.   2, for carbide tools, because of the sudden heat is more sensitive, as far as possible to make the tool evenly heated and evenly cooled, otherwise it is easy to cause chipping. Therefore, usually use oil-based cutting fluid with mild thermal conductivity and add the right amount of anti-wear additives. When cutting at high speed, the tool should be sprayed with a high flow of cutting fluid to avoid uneven heating. And this method can also effectively reduce the temperature and reduce the appearance of oil mist.   3, cast alloy (chrome cobalt tungsten) These alloys are non-iron elements, based on cobalt. When its temperature is higher than 600℃, it is harder and better wear resistance than HSS. This can be used for high-speed cutting, but also for non-cuttable alloys and cutting operations that generate high temperatures. Cast alloys are very sensitive to large changes in temperature, such as sudden interruptions in cutting operations. They are more suitable for continuous cutting operation, can use water-soluble cutting oil. 4, ceramic tools and diamond tools are often used in dry cutting process because they have more outstanding high temperature wear resistance than cemented carbide. Sometimes, in order to avoid high temperature, will also use the higher thermal conductivity of the water-based cutting fluid continuous and full pouring of the cutting area.   5, carbides are widely used in the metalworking industry and they are often called sintered carbides or superabrasives. They are made of tungsten, titanium, niobium, tantalum carbide powder added to the cobalt mold with high temperature heating sintering. Different types of sintered carbides can be produced by changing the ratio and type of metal carbide. Sintered carbides are used because they retain their hardness and wear resistance at temperatures as high as 1000°C. They are often used as inlays or can be used as a base. They are often used as inserted or replaceable cutting tips, each with different shapes and angles, which can be reassembled and stored as needed. Another easy way to make them is to cover the cutting head with a layer of carbide, which is made by vapor depositing titanium carbide onto a conventional carbide tool. Bits made in this way have high resistance to wear and the tool itself is less likely to chip. Carbide tools are often used in conjunction with water-soluble cutting oils, but they must be chosen carefully. Certain additives are will corrode the metal covered with cobalt.   6, ceramic / diamond ceramic cutting tools are mainly composed of aluminum oxide, can retain their hardness and wear resistance at high temperatures. However, as mentioned above, the harder the material, the more fragile, which makes ceramic tools are not suitable for discontinuous cutting or vibration load and temperature changes. Machining can use non-water-soluble cutting oil (oil-based cutting oil) or no cutting oil at all, to avoid the use of water-soluble cutting oil.   7、The hardest cutting tool is diamond, but it is also fragile. Diamond can engage in high content of aluminum processing operations, this alloy contains hard silicon particles, will quickly wear carbide tools. It is also suitable for grinding non-ferrous materials, such as stone and cement. Diamond can be oxidized at high temperatures, so it is not suitable for difficult alloys. Because it is particularly hard, it is often used in grinding applications. Oil-based cutting oils or water-soluble cutting oils or synthetic cutting fluids can be used.

CNC indexing head can provide a lot of convenience for some multi-sided products, it can process the workpiece at multiple angles at one time, so it can obviously reduce the process of processing   However, when the workpiece itself (especially when machining the side of the workpiece) is relatively high, or the fixture height is relatively high, there may be interference between the tool and fixture when changing the tool, which may cause damage to the tool or even the tool changing system, to prevent this problem, we should pay attention to the following points Placement of workpieces and fixtures on the table   Since the disc type tool changer is usually installed on the upper left side of the machine, the tool change will also take place on the left side of the spindle. When changing tools, a section of space under the tool arm will be temporarily used, so workpieces and fixtures should not be present here.   The table can be moved left and right, if the mounting position of workpiece and fixture is chosen on the left side of the table, then no matter how the table is moved, the workpiece and fixture will be on the left side of the spindle, which may not be a problem when the height of the workpiece and fixture is low, but once the workpiece and fixture conflict with the tool change action due to the height, then the workpiece and fixture will have to be removed and re-tuned.   Therefore, it is a good choice to use the right side of the table space as a priority. Selection of tool change point   Due to the condition, the tool change action has to be done at a specific point, and this point can be preferred to the upper left corner of the table.   Consistency of the tool change point   We have mounted the workpiece on the right side of the table and the safe tool change point has been set in the program, however, when the operator is resharpening or changing the tool, it is likely to forget about the tool change point and cause damage to the workpiece or tool.

In fact, a workpiece to see not only the strength of a manufacturer, but also to see his approach to some details. For cnc cnc lathe machining parts, if the manufacturer is not handled well, then this machining parts are not available, then in processing for manufacturers, should pay attention to what? First, the price surface burr, it can be said that for this point is a lot of manufacturers are easy to ignore, many people say this part out of what kind of time, that the finished package is what kind of time. In fact, otherwise, for a part, cnc cnc lathe machining parts is done through the equipment, then injection molding will produce cloak, and this burr is also generated at this time, if not timely trimming, or will be this part scrap. Otherwise will be in use will also affect the other links.   Second, the accuracy of the parts, for cnc cnc lathe machining parts, her accuracy is very strict, only to meet the required accuracy, can be used, and judge it this accuracy, mainly to see his ability to control the size, if the tolerance can fluctuate within the provisions, then this part is qualified, if beyond the tolerance, then it is not qualified. Third, the analysis of the test results, for a component, he will inevitably go through a performance test before leaving the factory, if the performance is qualified, then it will be factory, if not, then some of the reasons should be analyzed, so as to avoid the scrapping of large quantities, processing industry manufacturers will basically be so to deal with, they will be based on some of the performance of many homes, will Make a certain quality control chart, so as to analyze the causes.