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

The precision of hardware parts almost determines the quality of the product, and the higher the precision of hardware parts, the higher the requirement for precision. So, why does precision parts machining accuracy become worse? First, the parts themselves are poorly machined. Generally speaking, if the dynamic error between the shafts is not well adjusted during installation or changes due to wear and tear of the shaft drive chain, the accuracy of the parts will be affected. Generally, the accuracy check caused by such errors can be solved by readjustment compensation. If the error is too large or even if there is an alarm, you need to check the servo motor and observe whether its speed is too high.   Second, machine tool overshoot during operation can also affect machining accuracy, which may be due to acceleration and deceleration time is too short, the replacement time is properly extended. Of course, it is also likely that the connection between the screw and the servo motor is loose. Third, because of the two-axis linkage generated by the roundness overshoot, the machine is not properly adjusted to form the axial deformation of the circle, the axis of the screw clearance compensation is not correct or the axis positioning offset, which may affect the precision of precision parts.

The quality of precision parts machining parts affects the effectiveness of the machining method? Precision parts processing is the most common measure and means used in the industrial stage. For this technology, the first thing to consider is the quality and structure of the part itself; if poor quality parts are chosen, it will not help, regardless of the processing method used. Therefore, the quality of parts in parts machining is a very important step; speaking of parts, it is one of the indispensable products in many mechanical devices; parts are the basic elements of machine composition. Machines generally include one or more transmission parts for receiving external energy (such as electric motors, internal combustion engines, steam engines).   The implementation of the machine production functions of the executive part (such as machine tools in the tool), the original motion and power to the executive part of the transmission part (such as machine tools in the gear and screw drive mechanism), to ensure that the machine in the coordination of the work of the various parts of the detection and control system (such as machine tools in the CNC system) constitutes (that is, the machine by the original part, the transmission part, the executive part, the measurement and control part). The machine will be further decomposed, you can get all kinds of parts. Parts processing is the basic elements of the composition of the machine, can be broadly divided into two categories: one is available for a variety of machine parts (such as gears, shafts, etc.), known as general-purpose parts; the other is only used in a certain type of machine parts (such as bolts, propellers, etc.), known as special parts; in addition to some of the synergistic work of the parts composed of a combination of parts called parts or components (such as couplings, reducers, etc.).

Technical requirements in machining. 1, first of all, in machining, parts processing surface, there should be no scratches, scrapes and other defects that damage the surface of the parts. Parts to remove the oxide skin; uninjected shape tolerance should comply with the requirements of GB1184-80, uninjected length size allowable deviation ± 0.5mm; casting tolerance zone symmetry in the basic size configuration of the blank casting.   2. Processing of rolling bearing components are allowed to use oil heating for hot installation. Oil temperature should not exceed 100 ° C. Assembly of the hydraulic system allows the use of seal packing or sealant, but should be prevented from entering the system. Parts entering the assembly are assembly must have a certificate issued by the inspection department.   3, the parts must be cleaned before assembly, there should be no burrs, flying edges, oxide, rust, debris, oil, colorant and dust; before assembly should be the main fit size of the parts, especially the interference fit size and the related accuracy of the audit; parts in the assembly process does not allow knocking, touching, scratching and rusting.   4, mechanical processing in tightening screws, bolts, nuts, knocking or use of inappropriate screwdriver, wrench is strictly prohibited. Screw slot, nut, screw, bolt head shall not be damaged after tightening; fasteners with the specified tightening torque must be tightened with a torque wrench and tightened according to the specified tightening torque, and the excess adhesive flowing out shall be removed after bonding. 5, bearing outer ring and open bearing housing, bearing cover semi-circular hole should not be stuck; bearing outer ring should be in good contact with the open bearing housing semi-circular hole and bearing cover. It should be in contact with the bearing cover in the center line symmetry 120 ° and center line symmetry 90 ° range of uniform contact. In the above range with the plug ruler check, outer ring width of 1/3 shall not insert 0.03mm plug ruler.   6, bearing outer ring after assembly, should be positioned with the end of the bearing cover end contact evenly. After the rolling bearing is installed, it should be rotated flexibly and smoothly by hand. When fixing the shaft tile with a pin, the hole should be drilled in the hinge and the pin should be arranged when the mouth and end face of the shaft tile are flush with the opening and closing face and end face of the bearing concerned. Hole. The pin shall not be loosened after punched in.   7, alloy bearing lining surface yellowing, is not allowed to use, in the specified contact angle does not allow the phenomenon of denuclearization. The denuclearized area outside the contact angle shall not be greater than 10% of the total area of the non-contact area. Gear (worm wheel) reference end face and shaft shoulder (or locating sleeve end face) should be matched and checked with 0.05mm plug gauge. And should ensure that the gear benchmark end face and axis perpendicularity requirements.   8、Castings on the sand, core sand and core bone should be clean, castings have inclined parts, its size tolerance zone should be along the inclined side of the proportional configuration, castings do not allow the existence of detrimental to the use of cold partition, cracks, holes and other casting defects. Before painting, rust, oxide, grease, dust, mud, salt and dirt must be removed from the surface of all steel parts that need to be painted.

What are the material quality requirements for precision parts processing? In the manufacturing process of precision parts processing, the manufacturing process solutions are different due to the different production requirements and conditions of various parts. When the same parts are produced by different process solutions, their production efficiency and economic benefits are also different. Under the premise of ensuring the quality of the part, the process of developing a reasonable and feasible process solution with good overall technical and economic efficiency is called the process design of the part. In addition, there are certain requirements for the selection and quality of materials.   Not all materials can be precision machined, some materials are too hard, more than the hardness of the processed parts, it is possible to make the parts collapse, so these materials are not suitable for precision machining, unless the parts are made of special materials, or laser cutting.   With the material is divided into two categories of metal materials and non-metallic materials, for metal materials, the highest hardness is stainless steel, followed by cast iron; then copper, and finally aluminum; and the processing of ceramics, plastics and other non-metallic materials belong to the processing.   Regarding the hardness requirements of the material, in some occasions, the higher the hardness of the material, the better, but only the hardness requirements of the processed parts; the material to be processed should not be too hard. The material is moderately soft and hard, at least one notch lower than the hardness of the part. Also, it depends on the function of the processing equipment and the reasonable choice of the part material.   Precision machining still has some requirements for materials, not all materials are suitable for processing, such as too soft or too hard materials, the former does not need to be processed, the latter can not be processed. Therefore, the parts must pay attention to the density of the material before processing;, if the density is too large, which is equivalent to the hardness is also large, if the hardness exceeds the hardness of the machine (lathe turning tool), it can not be processed, not only will damage the parts, but also cause danger, such as knife flying out to injure people. Therefore, in general, for machining, the quality of the material should be lower than the hardness of the machine tool so that it can be processed.

For the production and processing of metal materials, a specific process is maintained. In the whole process of processing different types of metal materials mechanical parts processing will also ensure the development trend and practical operation of different processes. Then in the trend of developing suitable process operations, large precision parts will gain a lot of expertise and maintain versatility. There is a tendency to maintain a great deal of versatility in processing methods for achieving high precision in metallic materials. They will all get a lot of professional innovations and trends based on the application of specific metal material resources. Then the whole process of operation in the production process of different metal material resources will be based on the specific working ability to ensure the whole process of rational use of resources.   Ensure that the whole process of operation of a large number of production and processing technologies to obtain a better process execution. The development of precision parts processing is to transform the trend of intelligent production and processing and the application of the process. Different features are obtained to operate the whole process of machining. And the maintenance of new work capabilities is carried out throughout the process of operating specific work capabilities. In the whole process of different production metal materials in the processing of large precision parts, a large number of metal materials will be used, and a large number of metal products and machinery and equipment will be operated in the process at one time. Therefore, in the development of different characteristics of the whole process, to ensure the use of metal materials in the whole process. Then, the whole process of maintaining a suitable process will ensure that the whole process of processing will not be affected in any way.

What are the requirements of the raw material inspection standards for automotive precision parts processing? When outsourcing parts processing, the quality of automotive precision parts processing must be given high priority. Therefore, before the production and processing, sign a good outsourcing production and processing quality assurance agreement, which is conducive to binding each other's rights and obligations and presenting a favorable treatment plan for future dispute cases. Automotive precision parts raw materials guarantee.   1, the tenderer is obliged to show the processing enterprise product approval letter and other technical documents, the processing enterprise must refer to the implementation of the test.   2, the processor's incoming inspection must be carried out with reference to the relevant industry standards.   3、The processing party is responsible for the test results. Processing party found that the quality of raw materials failed or exceeded all normal range, must immediately notify the tender party quality inspection personnel.   4, automotive precision parts processing party's storage and logistics area must be strictly distinguished between high-quality goods area, inferior goods area, stalled goods area, etc., and clearly marked to ensure that the storage of natural environment to consider the quality of raw materials regulations and properly stored and applied.   5, the bidder shall ensure that the raw material processing plant lot number attainment rate ≥ 90%, electronic device material attainment rate ≥ 95%. When lower than the overall target, the processing party must closely cooperate with the tenderer to carry out inspection and guidance, and continue to fail for three months, the tenderer should make punishment or even replace the dealer.   6, the tenderer of the finished product inspection of raw materials, such as special selection due to certain types of defects, automotive precision parts processing party should be based on the results of the tenderer's judgment, can not be returned due to the same defects.   7, for the processing party test failed raw materials, the tenderer should be resolved within 2 working days to complete the raw materials subject to return and replacement, the tenderer should order the dealer to take away failed goods in 3 working days, after the tenderer determined that the automotive precision parts processing of poor raw materials should order the dealer to return in 5 working days.

The deviation of high precision mechanical parts processing mainly comes from CNC lathes, special tools, raw materials and their human errors; in order to facilitate the application of statistical standard tolerances, the part deviation normal distribution monitor is used to predict the deviation trend and pattern when batch processing mechanical parts production parts. It is well known that with the increase in precision of machining of high-precision mechanical parts, the production costs and difficulty factors increase; after statistical analysis of batch mechanical parts machining, the purpose of dimensional tolerances is to ensure the application of the entire equipment and product pipeline. Under the specified preconditions, if the deviation of the part obeys normal distribution, the tolerance level can be moderately liberalized after full consideration of the process performance of production and processing, so that the production of batch mechanical parts has good rationality.   All adjustable measurement point values in the whole process of precision parts machining vary from person to person, and the specification, appearance and surface of the part can rarely exceed the ideal value, so it is necessary to limit the error to a certain range to dimensional tolerances. If eigenvalues independently and identically distributed under any criterion were used for probability statistics, it would be very easy to machine high precision parts in batch machining of mechanical parts. The deviation of the part is mainly influenced by the random factors of the production and processing system software, so that the result will cause the specific specifications of the machined high precision mechanical parts will be relatively idealized with an error that is close to the normal distribution; the numerical idealized value of the specific specification, so that the statistical analysis of the standard tolerance will be applied to determine the dimensional tolerance of the part. So how to define the dimensional tolerance boundaries for batch machining of mechanical parts? On the one hand, it is necessary to ensure its functionality, and on the other hand to decenter the marks that appear in the production process, which in turn will lead to a more refined economic development.

Hardware non-standard parts processing processing precision machining is defined in accordance with the process and process of each steel part size or characteristics of the production process, including the flatness of the steel part, the surface finish layer, the flatness of the surface layer, the strength of the surface layer, so that the production and processing precision of the parts and production and processing process performance over the engineering drawings specified in the whole process. To put it bluntly, the flatness of non-standard parts processing regulations refers to the dimensional tolerances around non-standard high-precision machined steel parts such as rectangular frame steel parts, specifying the thickness of the four corners. Steel parts over a certain size. Tolerance category. If the precision measurement of the thickness of the four sides does not meet the dimensional tolerance requirements, it does not meet the flatness requirements. The steel part needs to be readjusted. The problem can occur with the glass suction cups of CNC grinders. The glass suction cup is damaged by overcoating, resulting in deviations in flatness. It will be that the grinding wheel is not repaired, or the grinding wheel is broken. At this point the grinding wheel must be replaced for non-standard parts machining and the glass suction cup must be removed again. Careful cleaning and finishing to prevent burrs. Non-standard parts machining flatness requirements are the sides and pavement of the steel parts exceed the dimensional tolerances specified, my understanding is that the cube, from the point of view of the number axis, is divided into three sides of XYZ. Generally, XZ and YZ are specified to exceed the dimensional tolerances specified. The deviation is also basically the same as the deviation specified for flatness. In non-standard high-precision machining, flatness requirements are generally addressed in accordance with the flatness regulations.

Precision parts processing equipment refers to the complete set of control, which can realize the electrification automation cabinet of motor switching control; it can be said that this kind of equipment has the functions of overload, short circuit, defect protection, etc., and the structure is very compact, more stable when working and more complete in function; if they form a distributed control system, they can also realize multiple devices through industrial Ethernet or industrial bus network. The reason why many electrification production are now using this kind of equipment is because this kind of equipment can be adapted to various sizes of industrialized control occasions. Industry insiders said that some domestic manufacturers of precision parts processing equipment can basically ensure the same function as the equipment produced by foreign groups, and can complete the automation of equipment and process automation, control to achieve a perfect network function. In addition, the performance of domestic imitation equipment is also quite stable, can be expanded, anti-interference ability is also particularly strong. It can be said that it is the heart and soul of modern industrial production in China; and it is important to know that some domestic manufacturers produce imitation equipment is designed according to the needs of domestic production and hitched to the human-machine interface touch screen, so that it can be operated more easily. Some people may not know the specific components of precision parts processing equipment, they often know that this equipment products are more common in the current domestic electrification production industry. In fact, for this equipment product manufactured in China, the main component is the air switch. The air switch is the power control part of the whole equipment and is an important key component that every equipment product must be equipped with. In addition, for the equipment, most of them have their own 24 volt power supply, but whether this power supply is needed depends on the actual situation. In addition, under normal circumstances, the device can send commands directly back to the control loop. It is also possible to pass the essential oil first and then transfer it. Be aware that when the command is sent, the relay action causes the relay on the control loop to be normally open or normally closed. Need to be developed according to the actual situation, so for many equipment production, the customer should confirm with the manufacturer, according to the actual situation before producing equipment products.

The machining of mechanical parts consists of several surfaces, and in order to study the relative relationship between the machined surfaces of the parts, a datum must be determined; the datum is the point, line and surface on the part that determines the position of other points, lines and surfaces. According to the different functions of the benchmark, the benchmark can be divided into two categories: design benchmark and process benchmark. Types of parts machining. Design benchmark: the benchmark used to determine the location of other points, lines and surfaces on the part drawing is called the design benchmark.   Process benchmark: the benchmark used in the process of parts processing and assembly is called the process benchmark. Process benchmark according to the different uses are divided into assembly benchmark, measurement benchmark and positioning benchmark.   (1) assembly benchmark: assembly used to determine the position of the part in the component or product benchmark is called the assembly benchmark.   (2) measurement benchmark: used to check the size and position of the processing surface benchmark called the measurement benchmark.   (3) positioning datum: the datum used to position the workpiece during processing, called the positioning datum. As a positioning reference surface (or line, point), in the first process can only choose the unprocessed rough surface, this positioning surface is called the rough benchmark. In each subsequent process can be used in the machined surface as a positioning reference, the positioning surface is called the fine reference. The development of process procedures. 1, the reference first: that is, the first processing reference surface. In the process of parts processing, should be processed first appearance as a positioning reference, in order to provide accurate benchmarks for the subsequent processes as soon as possible.   2, divided into processing stages: the processing quality requirements of the surface 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; easy to arrange the heat treatment process; and easy to find defects in the blank.   3, first face after the hole: for the box, bracket, connecting rod and other parts, should be processed first plane after processing holes. This can position the machined hole in the plane, to ensure the accuracy of the plane and hole position, 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 processing process route.