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

Precautions for turning copper screws When turning copper screws, it is necessary to know that the copper content of pure copper under normal conditions is 99.5%, and the hardness of pure copper under annealing is generally 35-45HB. In order to ensure the processing quality of copper screws, the following items should be noted when processing copper screws. When turning copper screws, it is necessary to know that the copper content of pure copper under normal conditions is 99.5%, and the hardness of pure copper under annealing is generally 35-45HB. In order to ensure the processing quality of copper screws, the following items should be noted when processing copper screws. 1. In the process of machining, chips may stick to the cutting edge, affecting the quality of copper screw machining and the service life of the tool. 2. The copper screw surface is easy to produce water like waveform and noise. 3. The expansion coefficient of pure copper is large. When cutting, deformation will occur due to high temperature, so it is difficult to master the size and accuracy of copper screw processing. 4. If the copper parts contain free cutting elements such as sulfur, the machinability of the copper parts will be affected. The toughness and plasticity of copper parts are relatively large, and the deformation generated during cutting is also large. Therefore, the cutter should be sharp, so that the cutting will be smoother, the temperature generated during cutting will be smaller, and the deformation of the copper sheet will be smaller. If lead is added to copper parts, machinability and cutting speed will be greatly improved. There are many kinds of bronze with poor anisotropy, but the machinability of lead bronze is greatly improved. In the processing of copper parts, the faster the cutting speed is, the smaller the cutting force is, so the deformation of copper parts in the processing process will be relatively small. The surface quality of copper alloy is very good, so there is no need for further finishing in the later stage. The faster the cutting speed is, the better the surface quality of the copper screw is.

What causes the deformation of aluminum alloy shell The machining deformation of aluminum alloy shells, especially thin-walled shells, is a common technical problem. Therefore, our machining plant must analyze the causes of deformation and take corresponding measures to prevent it. 1. The material grade and structural complexity of the aluminum shell will affect the deformation of the shell The deformation of aluminum shell machined by CNC is related to the complexity of the shape, aspect ratio and wall thickness, and is directly related to the rigidity and stability of the material. Therefore, when designing the aluminum shell of the product, the influence of these factors on the deformation of the workpiece should be minimized. In particular, the structure should be reasonable in the processing and customization of large part shells. Before processing, the hardness and porosity of aluminum alloy blanks shall be strictly controlled to ensure the quality of blanks and reduce the deformation of workpieces caused thereby. 2. Deformation of aluminum shell caused by machining and clamping of machining center When aluminum shell processing and material blank clamping, the correct clamping surface shall be selected first, and then the appropriate clamping force shall be selected according to the position of the clamping surface. Therefore, the clamping surface and the force bearing surface should be as consistent as possible so that the clamping force acts on the workpiece. When clamping forces in multiple directions act on the workpiece, the sequence of clamping forces shall be considered. The clamping force shall be applied first to make the workpiece contact with the support, which is not easy to be too large. The clamping force, which is mainly used to balance the cutting force, should be used in subsequent processes. 3. Deformation caused by processing parameters of aluminum shell During the cutting process of the machining center machine tool, the shell is affected by the cutting force, resulting in elastic deformation corresponding to the direction of the force, which is often referred to as the machining industry. In terms of processing parameters and tool selection, corresponding measures should be taken to deal with this deformation. Sharp tools are required for finishing. On the one hand, it can reduce the resistance formed by the friction between the tool and the workpiece, and on the other hand, it can improve the heat dissipation effect when the tool is cutting the workpiece. So as to reduce the residual internal stress on the workpiece. When milling the large surface of thin-walled casing parts, the single edge milling method is usually used. The cutter parameters adopt larger principal deflection angle and larger rake angle to reduce cutting resistance. The tool is widely used in production because of its light cutting, fast running and reduced deformation of thin-walled parts. In the custom machining process of thin-walled aluminum shell, a reasonable tool angle is crucial to the size of cutting force, the thermal deformation generated in the machining process and the micro quality of the workpiece surface. The size of the rake angle of the tool determines the cutting deformation of the tool and the sharpness of the rake angle. Large rake angle reduces cutting deformation and friction. However, if the rake angle is too large, the tool wedge angle will be reduced, the tool strength will be weakened, the tool heat dissipation will be poor, and the wear will be accelerated. Therefore, when machining aluminum alloy thin-walled cavities, high-speed tools and cemented carbide tools are generally used. The correct selection of cutting tools is the key to deal with the deformation of aluminum shell workpiece. In machining, the heat generated by the friction between the CNC machine tool and the workpiece will also deform the workpiece, so high-speed cutting is often used. In high speed machining, because the chip removal time is relatively short, most of the cutting heat is taken away by the chip, reducing the thermal deformation of the workpiece; Secondly, when working in the high-speed machining center, the reduction of the softening part of the cutting layer material can also reduce the deformation of aluminum shell processing, which is conducive to ensuring that the shell has accurate size, shape and size. In addition, the cutting fluid of CNC machine tool machining center is mainly used to reduce friction and cutting temperature during the cutting process. Reasonable selection of cutting fluid plays an indispensable role in improving tool durability, surface quality and machining accuracy. Therefore, in order to prevent the deformation of parts in the process of machining, it is necessary to reasonably use special cutting fluid with appropriate concentration. In CNC machining, the use of reasonable cutting process is an important link to ensure the accuracy of parts. When machining thin-walled aluminum shells with high precision requirements, generally symmetrical machining is used to balance the stress generated on the opposite side to achieve a relatively stable state, and the machined workpiece will be as flat as possible. However, when a lot of cutting is used in a certain process, the workpiece will be deformed due to the imbalance of tensile stress and compressive stress. The deformation of thin-walled aluminum shell in machining center is various. Some factors such as the clamping force when clamping the workpiece, the cutting force when cutting the workpiece 4. Deformation of aluminum shell in natural state after off machine of machining center After the aluminum shell is processed, the processing part itself has internal stress and deformation. To solve this problem, some workpieces need to be divided into rough machining and finish machining, that is, after the rough machining is completed, aging treatment or heat treatment is carried out to remove the stress, and then finish machining is carried out.

How to Prevent the Deformation of Precision CNC Machining Sleeve Parts The structural feature of sleeve parts is that the hole wall is thin, and thin-walled parts are often clamped during machining. Deformation caused by cutting force and thermal deformation. In this regard, Weimeite summarized some process measures to prevent part deformation: (1) Rough machining and finish machining are carried out separately to reduce the influence of cutting force and cutting heat, so the deformation of sleeve parts produced by rough machining CNC lathe can be corrected in the process of finish machining. CNC lathe processing sleeve (2) In the process of reducing the impact of clamping force, the following measures shall be taken to reduce the impact of clamping force: 1 When radial clamping is used for precision CNC machining, the clamping force should not be concentrated on a certain radial section of the workpiece, but should be distributed in a large area to reduce clamping on the unit area of the workpiece. The power of tightening. If the workpiece can be installed in a split ring of appropriate thickness, clamp it with the ring. Special jaws that increase the contact area can also be used. Open spindle clamps shall be used for locating holes. 2 The clamping force shall be located at the part with strong rigidity to improve the deformation of thin-walled parts under the clamping force. 3 Change the direction of clamping force, and change the radial clamping to axial clamping. 4 Precision CNC machining produces rigid process boss or process thread on the workpiece to reduce clamping deformation. Clamping with jaws with special structure during processing, and cutting off the flange at the end of processing. (3) Reduce the influence of cutting force on deformation: 1. Increase the rake angle and main rake angle of the tool to make the cutting edge sharper and reduce the radial cutting force. 2. The rough machining and finish machining shall be separated, so that the deformation of sleeve parts caused by rough machining can be corrected in the process of finish machining, and smaller cutting amount shall be adopted. 3 The inner and outer circular surfaces are processed at the same time to offset the cutting force. The heat treatment arrangement between roughing and finishing can reduce the influence of heat treatment deformation. Generally, sleeve parts will have large deformation after heat treatment, which can be corrected during finishing, but attention should be paid to properly increase finishing allowance.

Why does aluminum alloy precision parts deform? The machining deformation of aluminum alloy precision parts is mainly caused by such factors as blank cutting force, deformation caused by cutting heat, deformation caused by internal stress, and deformation caused by clamping force. We cannot allow deformed products to complete final assembly. Therefore, in order to reduce machining deformation, manufacturers of aluminum alloy precision parts can take various measures to improve the process to reduce deformation. The first technique is to reduce the internal stress of the blank. Aluminum alloy precision parts First: reduce the internal stress of the blank. Reduce the internal stress of the blank. Natural or artificial aging and vibration treatment can partially eliminate the internal stress of the blank; Or improve the cutting ability of the tool. The geometric parameters of the tool are selected reasonably, and the tool structure is improved. The second skill is to improve the clamping method of the workpiece. Secondly, improve the clamping method of the workpiece. For aluminum alloy thin-walled bushing parts, if a three jaw self centering chuck or spring chuck is used for radial clamping, the workpiece will inevitably deform once loosened after processing. At this time, the axial end face pressing method with good rigidity shall be adopted. According to the positioning of the inner hole of the part, the thread spindle is self-made and the inner hole of the part is sleeved. Press the end face with a cover plate, and then support it with a nut. When machining the excircle, the clamping deformation can be avoided, thus obtaining satisfactory machining accuracy. When machining aluminum alloy thin-wall and thin sheet workpieces, it is better to select vacuum suction cups to obtain uniformly distributed clamping force, and then use small cutting amount for processing, which can well prevent workpiece deformation. Third: Reasonably arrange the process In the high-speed cutting process, because of the large machining allowance and intermittent cutting, vibration often occurs in the milling process, which affects the machining accuracy and surface roughness. Therefore, NC high-speed cutting can generally be divided into rough machining - semi finishing - cleaning - finishing. For parts with high accuracy requirements, it is sometimes necessary to conduct secondary semi finishing and then finish machining. After rough machining, the parts can be naturally cooled to eliminate the internal stress generated by rough machining and reduce deformation. In addition to the above reasons, aluminum alloy parts will also deform during processing. In practice, the operation method is also very important. For parts with large machining allowance, symmetrical machining shall be adopted during machining in order to provide better heat dissipation conditions and avoid heat concentration.

Common problems and causes of lathe parts processing are detailed as follows: 1. Burr: During stamping or trimming, there is no residual material, and burr will occur under the section of steel plate. Cross sections are used for reference. When When the height of burr is more than 0.2mm, burr will occur. Iron powder will damage the mold and produce bumps. 2. Concave and concave: The surface of the material is abnormally convex or concave, which is caused by the incorporation of foreign matters (iron filings, dust). 3. Drum printing: the cleaning roller or the paper feeding roller is caused by the attachment of foreign matters (at a fixed interval). Normally, you can clear the print in the Foreign matter on the paper. 4. Sliding printing: occurs when the roller slides, stops suddenly or accelerates. 5. Crushing of coiled material may wrinkle at the edge: the guide roller of uncoiling line may be the gap between the guide rollers on the mold due to unwinding of the mold feed port It is caused by wrinkling. 6. Scratches: the main cause of scratches on parts. There are sharp scratches or metal dust falling into the mold. The preventive measure is to repair the Scratch and remove metal dust. 7. Bottom crack: The main reason for the bottom crack of this part is that the material is poor plasticizing or pressed too tightly on the mold compression ring. The preventive measures are more Replace the plastic or loosen the presser foot ring. 8. The sidewall has wrinkles: the main reason for the sidewall of the part to have wrinkles is that the thickness of the material is not enough (less than the minimum allowable thickness), or when the upper part The lower die is installed when the material at the lower part is eccentric, so that a large gap is generated at one side. The clearance is very small. The preventive measure is to replace the material And readjust the die.

The key technology of precision machining of lathe parts. Conventional machine tool design and manufacturing, all links are technically Very tolerant. Each link of the ultra precision machine tool is basically in a technical limit or critical application state, which link is considered or not treated slightly. Week, it will lead to overall failure. Therefore, it is necessary to have a very comprehensive and profound understanding of the whole machine tool system and each part of the technology in design. need According to the feasibility, proceed from the overall optimization, and carry out the comprehensive design in a very detailed way. Design and manufacture of machine tool body structure with high rigidity and stability Technology. Especially for LODTM machine tools, due to the large body, its own weight, and the large change in the weight of the bearing workpiece, any small deformation will affect the processing Precision. In addition to meeting the requirements in terms of materials, structural forms and processes, the structural design must also take into account the operability of the machine tool during operation. Ultra precision spindle technology for lathe parts. The scheme of aerostatic spindle is often adopted for medium and small machine tools. The aerostatic spindle has small damping and is suitable for high speed Rotary machining application, but the bearing capacity is small. The rotary accuracy of aerostatic spindle can reach 0.05 μ m。 LODTM machine tool spindle bearing workpiece ruler With large size and weight, hydrostatic spindle is generally preferred. Hydrostatic spindle has large damping, good vibration resistance and large bearing capacity, but High speed heating, liquid cooling and constant temperature measures shall be taken. Hydrostatic spindle rotation accuracy can reach 0.1 μ m。 To ensure the accuracy and stability of the spindle No matter the air pressure source or the hydraulic pressure source, it needs constant temperature, filtering and precision control of pressure. High precision air, liquid, temperature, vibration and other working environment control technologies for lathe parts. Vibration isolation and horizontal attitude control of machine tool. Vibration for ultra precision machining The influence of is very obvious, and far driving cars have influence. Special foundation treatment and air floating vibration isolation composite measures shall be taken for machine tool vibration isolation Implementation. The air floating vibration isolation system of the machine tool body shall also have the automatic leveling function to prevent the influence of the horizontal state change on the processing during the processing of the machine tool. about For machine tools with high LODTM vibration isolation requirements, the natural frequency of the vibration isolation system is required to be below 1HZ  

The CNC lathe feed processing route refers to the turning tool moving from the tool setting point (or the fixed zero point of the machine tool) until returning to the point and ending the processing program The path through, iCNCluding the path of cutting and the non cutting empty travel path such as tool entry and exit. The feeding route of finish machining is basically carried out along the contour of the part. Therefore, the key to determine the feeding route is to determine the rough machining And the feed route of the empty stroke. In CNC lathe processing, the determination of the processing route should generally follow the following priCNCiples. ① The precision and surface roughness of the workpiece to be machined shall be guaranteed. ② Shortest processing route, reduce idle travel time and improve processing efficieCNCy. ③ The workload of numerical calculation shall be simplified as much as possible, and the processing program shall be simplified. ④ For some reused programs, subprograms shall be used.

The hardware processing process is to open materials according to production needs. After opening, for example, small parts can be produced by punching machine and then gongs can be cut Or CNC processing, which is a lot in the production of eyewear accessories and auto accessories. For container, it is to burn after the blanking and punching machine Welding, sanding, oil spraying, and then assembling the parts can be shipped. And there are many polished hardware accessories Surface treatment, electroplating or oil spraying. Then welding or screwing, assembling, packaging and shipping. 1. Spray painting processing: the hardware factory adopts spray painting processing when producing large hardware finished products, so as to prevent the hardware from producing Rust, such as daily necessities, electrical enclosures, handicrafts, etc 2. Electroplating: electroplating is also the most common processing technology for hardware processing. The surface of hardware is electroplated through modern technology to ensure production The products will not mildew or embroider after long time use. The common electroplating processes are: screws, stampings, battery chips, car parts, small accessories, etc, 3. Surface polishing: surface polishing is generally used in daily necessities for a long time, and the surface burrs of hardware products are treated, such as: We produce a comb. The comb is a metal part made by pressing. The corners of the punched comb are very sharp After polishing, the sharp edges and corners will be polished into a smooth face, so that no harm will be caused to the human body during use. Turning cylindrical surface is the basic method for metal processing, and the equipment used is a lathe. In general machinery plants, lathes account for the total number of machine tools About 40% of the number of units. Turning is the main method for roughing and semi finishing the cylindrical surface of various materials, and it is also the most important method for various materials that are not suitable for grinding Final finishing method. In case of small batch production of single piece, the turning of cylindrical surface is generally carried out on an ordinary lathe. Multi tool semi-automatic lathes or automatic lathes are widely used in mass production Lathe. Large disc parts shall be processed on vertical lathe. Large long shaft parts need to be processed on heavy horizontal lathe. The characteristics of turning the cylindrical surface are: 1. The tool is simple, easy to manufacture, sharpen and install; 2. The cutting process is stable, and the cutting force fluctuation is small It is beneficial to adopt high cutting speed and improve productivity; 3. The machine tool has good versatility, and can process the excircle, end face, inner hole Threads and chamfers, etc. The mutual position accuracy between surfaces can be easily guaranteed; 4. It is suitable for finishing of nonferrous metal parts.

1. Spray painting processing: the hardware factory adopts spray painting processing when producing large hardware finished products, which can prevent hardware from rusting Such as: daily necessities, electrical enclosures, handicrafts, etc 2. Electroplating: electroplating is also the most common processing technology for hardware processing. The surface of hardware is electroplated through modern technology to ensure long product length There is no mildew or embrittlement under the use of time. Common electroplating processes include: screws, stampings, battery chips, car parts, small accessories, etc, 3. Surface polishing: surface polishing is generally used in daily necessities for a long time. Through surface burr treatment on hardware products, for example, we Produce a comb. The comb is a metal part made by pressing. The corners of the punched comb are very sharp The sharp parts of the edges and corners will be polished into smooth faces, so that no harm will be caused to the human body during use. Turning cylindrical surface is the basic method for metal processing, and the equipment used is a lathe. In general machinery plants, lathes account for the total number of machine tools About 40% of the number. Turning is the main method for roughing and semi finishing the cylindrical surface of various materials, and it is also the final method for various materials that are not suitable for grinding Finishing method. In case of small batch production of single piece, the turning of cylindrical surface is generally carried out on an ordinary lathe. Multi tool semi-automatic lathes or automatic lathes are widely used in mass production Lathe. Large disc parts shall be processed on vertical lathe. Large long shaft parts need to be processed on heavy horizontal lathe. The characteristics of turning the cylindrical surface are: 1. The tool is simple, easy to manufacture, sharpen and install; 2. The cutting process is stable and the cutting force fluctuation is small, which is conducive to mining Use high cutting speed to improve productivity; 3. The machine tool has good versatility, and can process the excircle, end face, inner hole, thread and chamfer in one clamping Angle, etc. The mutual position accuracy between surfaces can be easily guaranteed; 4. It is suitable for finishing of nonferrous metal parts.

  ① Press on the material. The traditional die design structure is overcome, and the material holding gap is opened on the discharge plate. In this way, the movement of the unloading plate in the stamping is stable, while the material ② Reasonable mold design. The arrangement of blanking sequence may affect the forming accuracy of stamping parts. For blanking of small parts of stamping parts, generally The blanking of small area is arranged to reduce the impact of blanking force on the forming of stamping parts. ③ Add strong pressure function. Namely, the pressing part of the unloading insert is thickened to increase the pressure on the material at the die side, thus inhibiting the production of stamping parts during blanking ④ The end of the punch edge shall be chamfered or curved. This is an effective way to reduce the blanking force. Reduce the buffer cutting force, which can reduce the stretching of the material on the die side The effect of material and distortion. ⑤ In daily die production, attention should be paid to maintaining the sharpness of the cutting edges of the punch and die. When the cutting edge is worn, the tensile stress of the material will increase The trend increases.