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

We know that precision machining according to the processing object can be divided into standard parts processing and non-standard parts processing, relatively speaking, standard parts processing is relatively easy, while the processing of non-standard parts is relatively difficult, many people do not distinguish what is standard parts what is non-standard parts, then the next I will introduce what is called non-standard parts it. First of all, we know that non-standard parts are proposed relative to standard parts, so before understanding non-standard parts we need to know what is meant by standard parts. Standard parts refer to the structure, size, drawing, marking and other aspects have been completely standardized, and the common parts produced by professional factories, like threaded parts, rolling bearings, etc.. In a broad sense, it includes standardized fasteners, links, transmission parts, seals, hydraulic components, pneumatic components, bearings, springs and other mechanical parts. Narrow sense only includes standardized fasteners. Domestic commonly known as standard parts is the abbreviation of standard fasteners, is a narrow concept, but can not exclude the existence of the broad concept. In addition, there are industry standard parts, such as automotive standard parts, mold standard parts, etc., also belong to the broad sense of standard parts.   Non-standard parts processing professionals to elaborate is mainly the state did not set out strict standard specifications, no relevant parameters outside the provisions of the enterprise free control of other accessories. There are many varieties of non-standard parts, there is no very standard classification. Roughly classified as follows. Metal non-standard parts:   By the customer to provide drawings, manufacturers according to the drawings using equipment to produce the corresponding products, usually the majority of molds, tolerance requirements, finish are prescribed by the customer, there is no certain paradigm. Products from casting to finishing completely need the corresponding quality control, the process is complex and variable, and the general cost is higher than standard parts.   Non-metallic non-standard parts.   It is the processing of some non-metallic materials. Such as plastic, wood, stone, etc. In recent years, the injection molding industry, the development of plastic molds increasingly sophisticated, surface design, programming CNC references, so that the cost of non-standard processing and tolerance levels have been greatly improved.  

What measures can be taken to ensure the processing quality of drilling holes that occupy a large proportion in CNC precision processing plants Drilling is a basic method of hole processing, which occupies a large proportion in Shenzhen CNC precision processing plant. The tools used for drilling are shoulder drills and fried dough twist drills, which can process holes on solid materials. Due to the large cutting load, poor tool stiffness and the shortcomings of the drill structure during drilling. When drilling, the following problems often occur: the drill is easy to deflect, causing the offset of the hole axis and straightness error; The aperture is easy to expand; Rough hole wall; Large axial force during drilling. So drill bit Generally, it can only be used for machining holes with low precision requirements, or for rough machining of holes with high precision requirements. The general dimensional accuracy of drilling is T11~T14, and the surface roughness is Ra60~12.5m. In order to ensure the processing quality, the following measures are adopted in the process: (1) Before drilling, the end face shall be machined to ensure that the end face is perpendicular to the drill to prevent deviation. (2) During tool grinding, the two main cutting edges of the drill shall be symmetrical as far as possible, so that the radial cutting force generated by the two cutting edges is consistent. (3) Shenzhen CNC precision processing plant uses drilling jigs as guiding devices, which can reduce the deviation at the beginning of drilling, especially on the inclined plane or curved surface. (4) Small feed rate shall be adopted when drilling small or deep holes.

Repair of CNC Machine Tools in Precision Parts Processing Repair in precision parts processing refers to the operation of replacing old parts with the same new parts or processing and repairing old parts to ensure the normal and safe operation of the CNC machine tool in use. These operations shall not change the characteristics of the CNC machine tool. Precision parts processing In the process of precision parts processing, various parts in CNC machine tools have different experiences in reaching the wear limit. Whether from a technical or economic perspective, it is not allowed to replace all worn parts with only one repair. However, it is not allowed to specify too much, which affects the effective use time of CNC machine tools. Generally, repair is divided into three types, namely, major repair, medium repair and minor repair.

Definition of Just in Time Production System in Precision Parts Processing The traditional production management system in precision parts processing is generally to supply parts from the previous process to the next process, and increase WIP reserves to deal with problems such as imbalance and accidents in production and changes in demand. The disadvantage of this method is that no matter whether the parts required by the next process are used up in the previous process, the parts will be delivered to the next process when they are produced, which will easily lead to the backlog of WIP in the next process. In order to overcome the above shortcomings, just in time production came into being. Precision parts processing The key point of just in time production system in precision parts processing is just in time, that is, only necessary products (parts, components, finished products) are produced in necessary quantities when necessary. Its goal is to reduce the WIP reserve to the minimum, so as to save funds to the maximum extent, make the best use of manpower and equipment, improve efficiency and reduce costs. At the same time, the system is flexible. In terms of human factors, production workers are required to have high enthusiasm and play a greater role.

Significance of Kanban Management in Precision Parts Processing In precision parts processing, the JIT system uses Kanban as a tool to link the previous and next processes to form a flow process for JIT production. Kanban, also known as the voucher card, is a piece of card, which is filled with the name, number, material, production quantity, production time, weight, processing place, delivery place, delivery time, working position appliances and capacity of parts in advance. Each kanban is fixed to represent a certain number of parts, such as one piece, or ten pieces. Kanban must be circulated along with the physical objects. Precision parts processing Kanban management in precision parts processing is to transfer operation instructions within the enterprise and between the enterprise and cooperative enterprises according to the requirements specified on the Kanban, that is, use Kanban to order and receive goods from the general assembly to the previous process, so that each production process can obtain the necessary quantity of necessary products (or parts) at the necessary time, so as to achieve punctual production and eliminate unnecessary WIP, To achieve the fundamental goal of completely eliminating waste.

High speed cutting technology in CNC precision machining plant The high-speed cutting technology of Shenzhen CNC Precision Machining Factory is also one of the key technologies for successful high-speed machining. The improper selection of cutting method will aggravate the tool wear and completely fail to achieve the purpose of high-speed machining. High speed cutting technology includes the selection and optimization of cutting methods and cutting parameters, the selection of cutting methods, tool materials and tool geometric parameters for various materials. 1. Selection and Optimization of Cutting Methods and Parameters In high speed cutting, cutting methods and cutting parameters must be optimized. It includes optimizing the control of cutting tools, such as the direction of tool approaching the workpiece, the angle of approach, the direction of movement and the cutting process (down milling or up milling). CNC machining 2. Cutting methods for various materials Cutting aluminum, copper and other light alloys is different from cutting steel, cast iron and alloy steel that is difficult to machine. Because of the different cutting mechanism, in addition to the selection of tool materials and tool geometric parameters, different cutting strategies must be adopted in the cutting process to obtain better cutting results. It is also one of the important contents of high-speed cutting technology research to study high-speed cutting technology according to different machining materials. 3. Selection of tool materials and geometric parameters In the research of high-speed cutting technology in Dongguan CNC Precision Machining Factory, cutting methods and technologies must be closely combined with the selection of tool materials and tool geometric parameters. High speed cutting technology research is a very meaningful work. It has been proved that if only high-speed machine tools and cutters are available without good process technology as guidance, expensive high-speed machining equipment can not fully play its role. The technology of high-speed cutting is very different from the traditional technology, and it is far less mature and popular than the traditional technology. This is a problem that should be paid special attention to in the application of high-speed machine tools.

Crankshaft is one of the key components of automobile engine, and its performance directly affects the life of automobile. When the crankshaft is working, it bears heavy load and constantly changing bending moment and torque. The common failure forms are bending fatigue fracture and journal wear. Therefore, the crankshaft material is required to have high rigidity, fatigue strength and good wear resistance. 1. Foundry Technology (1) Smelting For the melting of high-grade cast iron, large capacity intermediate frequency furnace or variable frequency intermediate frequency furnace will be used for melting, and direct reading spectrometer will be used to detect the composition of molten iron. Spheroidal graphite cast iron is treated by subcontracting, new varieties of nodulizing agent are developed, and advanced inoculation methods such as stream inoculation, in mold inoculation and compound inoculation are adopted. The parameters of melting process are controlled by microcomputer and displayed on screen. Development Trend of Crankshaft Manufacturing Technology in the Future (2) Modeling EPC will be developed and popularized. In sand casting, boxless injection molding and extrusion molding will be attached importance to and continue to be popularized in new or rebuilt plants. The original high-pressure molding line will continue to be used, and some key components will be improved to realize automatic core assembly and core lowering. 2. Forging technology Automatic lines with hot die forging presses and electrohydraulic hammers as the main machines are the development direction of forging crankshaft production. These production lines will generally adopt precision shearing blanking, roll forging (cross wedge rolling) billet making, medium frequency induction heating, etc. 3. Machining technology In rough machining of crankshaft, CNC lathes, CNC internal milling machines, CNC broaching machines and other advanced equipment will be widely used for CNC turning, internal milling, and turning broaching of the main journal and connecting rod journal to effectively reduce the deformation of crankshaft processing. CNC controlled crankshaft grinder will be widely used to finish the crankshaft journal. This grinder will be equipped with automatic dynamic balancing device of grinding wheel, automatic tracking device of center frame, automatic measurement, automatic compensation device, automatic dressing of grinding wheel, constant linear speed and other functional requirements to ensure the stability of grinding quality. It is estimated that the current situation of high precision equipment relying on imports will not change in the short term. 4. Heat treatment technology and surface strengthening technology (1) Medium frequency induction hardening of crankshaft Medium frequency induction hardening of crankshaft will adopt microcomputer monitoring closed-loop medium frequency induction heating device, which has the characteristics of high efficiency, stable quality and controllable operation. (2) Crankshaft soft nitriding For crankshafts produced in large quantities, in order to improve product quality, a nitrogen based atmosphere gas soft nitriding production line controlled by a microcomputer will be adopted in the future. The nitrogen based atmosphere gas soft nitriding production line consists of a front cleaner (cleaning and drying), a preheating furnace, a soft nitriding furnace, a cooling oil tank, a rear cleaner (cleaning and drying), a control system, a gas preparation and distribution system, etc. (3) Surface strengthening technology of crankshaft The fillet rolling strengthening of nodular cast iron crankshaft will be widely used in crankshaft processing. In addition, the composite strengthening processes such as fillet rolling strengthening and journal surface quenching will also be widely used in crankshaft processing. The strengthening method of forged steel crankshaft will adopt more journal and fillet quenching. Main causes of crankshaft fracture: (1) Engine oil deteriorates after long-term use; Serious overloading and over coupling lead to long-term overload operation of the engine and tile burning accident. The crankshaft was severely worn due to the burning of the engine bush. (2) After the engine is repaired, the loading does not pass the running in period, that is, the engine is overloaded, and the engine is overloaded for a long time, which makes the crankshaft load exceed the allowable limit. (3) During the repair of the crankshaft, overlaying welding was used, which destroyed the dynamic balance of the crankshaft and did not check the balance. The unbalance exceeded the standard, causing greater vibration of the engine and fracture of the crankshaft. (4) Due to poor road conditions and serious overloading and over coupling of vehicles, the engine often runs within the critical speed of torsional vibration, and the shock absorber fails, which will also cause crankshaft torsional vibration fatigue damage and fracture.

At present, there are several precision parts processing machinery and equipment manufacturing companies on the market in China, each from two different system software. First, many former state-owned companies separated many original business processes according to the reform to create separate machinery and equipment manufacturing enterprises; The second is that many professional and technical independent components have some private enterprises, which together produce the current domestic machine tool manufacturing industry. The level of automation technology determines the development trend of the processing field. Nowadays, most metal material parts can be processed automatically or semi automatically. The quality of the parts produced automatically is stable and reliable. For high-precision parts with more quality regulations, it is more necessary to complete their automatic production. How to complete the automation technology for precision parts processing? How to Complete Automation Technology in Precision Parts Processing Precision parts are processed with CNC machine tools, also known as CNC machining. The biggest difference between CNC machining and general machine tool processing is that the posture achieved by CNC machining is adjusted according to the predetermined process. Driven by the demand of all Chinese precision parts processing markets, the requirements of China's machine tool manufacturing industry are bound to increase again rapidly, with an annual growth rate of 37.4%, becoming the fastest among all machine tools. China has also invested a large amount of capital in this industry to help the development of the field. Not only has the rapid progress of CNC machine tools, but also the manufacturers of CNC machine tools in China have also obtained good opportunities and obtained greater development.

In precision part machining, the path of tool position relative to part motion is called machining path. The processing routes are as follows. Hole processing route: The hole processing route refers to the distance between the tool tip position and the upper surface of the hole when the tool changes from fast forward to tool forward during hole processing. The processing route of the hole system with high mutual position accuracy. For the processing of the hole system with high position accuracy requirements, special attention should be paid to the arrangement of the hole processing sequence to avoid bringing the directional clearance of the coordinate axis into the hole system and affecting the position accuracy. Cleaning and processing route of the contour: When the side edge of the end mill is used to clean the contour parts, in order to reduce the tool receiving trace and ensure the surface quality of the parts, the cutting in and cutting out points of the milling cutter shall cut into the part surface along the tangential direction of the extension line of the contour curve of the parts, instead of directly cutting into the parts along the normal direction of the contour curve of the parts, so as to avoid tool marks on the processing surface and ensure the smooth contour of the parts. Principles of processing routes for precision parts Principles of processing routes for precision parts Machining route of groove workpieces: There are three methods for machining grooves, namely, line cutting, circular cutting and first cutting and last circular cutting. The above three are the three workpiece processing routes used in precision parts processing.

Metal stampings refer to steel/nonferrous metal and other sheet metal dies, which are formed to the specified shape with the pressure required for processing provided by the press at room temperature. Compared with other methods of mechanical processing and plastic processing, stamping has many unique advantages in both technical and economic aspects. The main performances are as follows. (1) The production efficiency of metal stamping is high, and the operation is convenient, and it is easy to realize mechanization and automation. This is because metal stamping depends on stamping dies and stamping equipment to complete the processing. The number of strokes of ordinary presses can reach dozens of times per minute, and the high-speed pressure can reach hundreds or even thousands of times per minute. In addition, each stamping stroke may result in a stamping part. (2) During metal stamping, because the die ensures the size and shape accuracy of the metal stamping parts, and generally does not damage the surface quality of the stamping parts, and the life of the die is generally long, the quality of metal stamping is stable, the interchangeability is good, and it has the characteristics of "identical". (3) Hardware stamping can process parts with large size range and complex shape, such as stopwatch of clocks and watches, longitudinal beam of automobiles, covering parts, etc. In addition to the cold deformation hardening effect of materials during metal stamping, the strength and stiffness of metal stamping are high. (4) Hardware stamping generally does not generate chips and scraps, with less material consumption and no need for other heating equipment, so it is a material saving and energy-saving processing method, and the cost of hardware stamping parts is low.