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

What are the difficulties in processing medical device parts In the face of the epidemic situation in the last few years, the medical device industry is showing a dynamic growth trend. The processing of medical devices is required to be higher by difficult to process materials, complex workpiece shapes and frequent small batch production. So what problems will exist when processing medical device parts? Dongguan Lifei Xiaobian explains the new problems faced by medical parts processing for everyone? The medical device industry has put forward new requirements for professional precision tools Difficult to machine materials, complex workpiece shapes and frequent small batch production put forward high requirements for cutting tools used to process professional medical devices. For example, transplant products and artificial limbs play a very important role in successful surgical operations and can help surgeons achieve the best medical results. The quality of medical devices is largely determined by the cutting tools for processing medical devices. 1、 Processing materials of medical spare parts are difficult to process: 90% of medical device implant components are made of Ti6Al-4V titanium alloy, which is light, high strength and high biocompatibility. Titanium alloy 6AL-4V has become the most commonly used material for medical implant devices. Titanium alloy 6AL-4V is usually used for the fabrication of hip joints, bone screws, knee joints, bone plates, dental implants, and spine connecting elements. Titanium alloy has the characteristics of work hardening. In the machining process, the shearing angle is large, the chip generated is thin, and a relatively small contact area is formed on the tool. In addition, the high cutting force in the machining process, combined with the friction force during chip flow, will comprehensively lead to excessive local cutting heat of the tool. However, because of the poor thermal conductivity of titanium alloy, the cutting heat cannot be transferred quickly. Therefore, a large amount of cutting heat is concentrated on the cutting edge and tool surface. High cutting force and cutting heat will comprehensively cause crescent depression and rapid tool failure. 1. Reliable and compact machine tool fixture Medical device processing equipment needs to be able to process small and complex parts made of difficult to process materials (such as titanium alloy or stainless steel) with high accuracy requirements, such as processing bone and joint substitutes. Due to the poor cutting performance of the material to be machined, the blank is usually bar stock - which means that a large amount of metal needs to be removed. As a result, some parts are cast to the shape close to the finished product, but this also adds to the trouble of making complex and expensive fixtures. Another factor that increases processing complexity is the narrow tolerance range. Medical device parts require high workpiece materials, processing accuracy, surface finish, etc., which requires high reliability of the processing system. Thus, it puts forward high requirements for machine tools, jigs, tools, CAM software, etc. Workpieces are usually processed on advanced medical equipment such as Swiss automatic lathes, multi spindle machine tools and rotary worktables. These machine tools are mostly characterized by very small size and compact structure

What kinds of precision CNC metal cutting fluids are there? Cutting fluid is an industrial fluid used to cool and lubricate tools and workpieces during metal cutting and grinding. What kinds of metal cutting fluids are there? In the cutting fluid, the main component of the aqueous solution is the water cooling performance liquid, which is also convenient for the operator to observe during machining; Emulsion is mainly made of mineral oil and emulsified ointment diluted by 95% - 98% water. It has good fluidity, cooling property and low lubricating performance. Emulsion combines the advantages of oil and water, and has good lubricating and cooling properties, so it has a better effect on metal cutting at high speed, high temperature and low pressure. In addition to cutting difficult to machine materials, emulsion can also be used for all light and medium load cutting and most heavy load machining, and emulsion can also be used for all grinding except for complex grinding. However, the disadvantages of emulsion are also very prominent. When contacting with air, it is easy for bacteria to multiply, which will corrupt and deteriorate the emulsion. Therefore, organic bactericides with weak toxicity should be added generally. High concentration emulsion is used for rough turning and grinding. Low concentration emulsion is used for fine turning, drilling and milling; Cutting oil is mainly mineral oil, and only a few animal and vegetable oils or composite oils are used. In actual use, additives are added to improve its lubrication and rust prevention performance. Its lubrication performance is excellent, but its cooling performance is poor. It is mainly used for gear processing, milling, reaming, machining, etc.      

What are the characteristics of CNC machining 1. The drive chain is short. Compared with ordinary machine tools, the spindle drive is no longer a motor belt gear pair mechanism, but a transverse and longitudinal feed are driven by two servo motors respectively. Traditional components such as change gears and clutches are no longer used. The drive chain is greatly shortened. 2. High rigidity. In order to match the high precision of the CNC system, the rigidity of the CNC machine tool is high, so as to meet the requirements of high-precision processing. 3. Light drag, ball screw pair is used for tool rest (workbench) movement, with small friction and easy movement. The supporting special bearing at both ends of the lead screw has a larger pressure angle than the ordinary bearing, which is selected and matched when leaving the factory; The lubrication part of the CNC machine tool adopts oil mist automatic lubrication, which makes the CNC machine tool portable. Machining characteristics of CNC machine tools 1. High degree of automation can reduce the physical labor intensity of operators. The NC machining process is automatically completed according to the input program. The operator only needs to start tool setting, load and unload the workpiece, and replace the tool. During the machining process, the main task is to observe and supervise the machine tool operation. However, due to the high technical content of CNC machine tools, the mental labor of operators is improved accordingly. 2. The machining parts have high precision and stable quality. The positioning accuracy and repeated positioning accuracy of CNC machine tools are very high, which makes it easier to ensure the consistency of the size of a batch of parts. As long as the process design and program are correct and reasonable, combined with careful operation, it can ensure that the parts can obtain high processing accuracy, and it is also convenient to implement quality control on the processing process. 3. High production efficiency. NC machine tool processing can process multiple processing surfaces in the clamping process again, and generally only the first piece is detected. Therefore, many intermediate processes such as scribing, size detection, etc. can be saved during the processing of ordinary machine tools, reducing the auxiliary time. Moreover, because the quality of parts processed by NC is stable, it brings convenience to the subsequent processes, and its overall efficiency is significantly improved. 4. It is convenient for new product development and modification. NC machining generally does not require a lot of complex process equipment. Parts with complex shape and high accuracy requirements can be processed by compiling processing programs. When the product is remodeled or the design is changed, only the program needs to be changed, but the tooling does not need to be redesigned. Therefore, NC machining can greatly shorten the product development cycle, providing a shortcut for the development of new products, product improvement and modification. 5. It can be developed to a more advanced manufacturing system. CNC machine tools and their processing technology are the basis of computer aided manufacturing. 6. The initial investment is large. This is due to the high cost of CNC machine tools, long preparation period for the first machining, and high maintenance costs. 7. High maintenance requirements. CNC machine tools are typical products of technology intensive mechatronics, which require maintenance personnel to understand both machinery and microelectronics maintenance, as well as better maintenance equipment.

7075 aluminum alloy is a cold treated forging alloy with high strength, much better than mild steel. 7075 is one of the most powerful commercial alloys. 7075 materials are generally added with a small amount of copper, chromium and other alloys. Among them, 7075-T651 aluminum alloy is particularly superior. It is known as the best product of aluminum alloy, with high strength and superior to any mild steel. The alloy has good mechanical properties and anodic reaction. Its representative uses include aerospace, mold processing, mechanical equipment, tooling and fixtures, especially for manufacturing aircraft structures and other high stress structures with high strength and corrosion resistance. How to know what 7075 aluminum alloy is? Let Noble Smart Manufacturing tell you National standard: 7A09 GB/T3190 -- 1996 Japanese standard: A7075 JIS H4000-1999 JIS H4080-1999 Non standard: 76,528 IS 733-2001 IS737-2001 Russian standard: B95/1950 rocT 4785-1974 EN:EN AW-7075/AlZn5.5MgCu EN573-3-1994 German standard: AlZnMgCu1.5/3.4365 DIN172.1-1986/w-nr French standard: 7075 (A-Z5GU) NFA50-411 NFA50-451 British Standard: 7075 (C77S) BS 1470-1988 American standard: 7075/A97075 AA/UNS physical characteristics Tensile strength: 524Mpa 0.2% yield strength: 455Mpa Elastic modulus E: 71GPa Hardness: 150HB Density: 2.81g/cm ^ 3 Main purpose Aerospace industry, blow molding (bottle) mold, ultrasonic plastic welding mold, golf ball head, shoe mold, paper plastic mold, foam molding mold, wax removal mold, model, fixture, mechanical equipment, mold processing, used to make high-end aluminum alloy bicycle frame. chemical composition Silicon Si: 0.40 Fe: 0.50 Copper: 1.2-2.0 Manganese Mn: 0.30 Mg: 2.1-2.9 Chromium Cr: 0.18-0.28 Zinc: 5.1-6.1 Titanium: 0.20 Aluminum Al: allowance Others: single: 0.05 Total: 0.15 characteristic 1. High strength heat treatable alloy. 2. Good mechanical performance. 3. Good usability. 4. It is easy to process and has good wear resistance. 5. Good corrosion resistance and oxidation resistance. mechanical property 1. Tensile strength σ b (MPa):≥560 2. Elongation stress σ p0.2 (MPa):≥495 3. Elongation δ 5 (%):≥6 Note: Mechanical properties of seamless pipe Sample size: diameter>12.5

CNC batch processing refers to the industrial manufacturing behavior of manufacturing 10-10000 pieces of products or parts at one time using CNC numerical control processing technology. In the current mechanical processing and manufacturing industry, there are countless CNC batch processing enterprises. At the moment of rapid development, there are two types of production: mass processing (production) and small batch processing (production), that is, small batch production of multiple varieties and single pieces and large batch production of fewer varieties and most quantities. The former is the main body of the machinery industry. Many companies in the CNC processing industry have done so, including the Shenzhen Noble Intelligent Manufacturing Company we mentioned. How to define CNC mass processing and CNC small batch processing: CNC mass processing usually involves tens of thousands of products, which often require mold opening, such as plastic mold, die-casting mold, cold stamping mold, etc; At the same time, tooling fixtures are also required, such as milling fixtures, grinding fixtures, turning fixtures, drilling fixtures for bench workers and other special fixtures. Under the premise of mold opening and fixture making, the production efficiency has been greatly improved, which is easy to produce scale effect. The number of parts processed by CNC in small batches ranges from one digit to three digits. They are processed by simple molds, soft molds, or directly by CNC equipment. Generally, they include turning, milling, planing, grinding, pliers and other common machining processes, as well as the cutting, drawing, drilling, tapping, etc. of bench workers. This kind of processing method saves costs and speeds up the market cycle of products,

Technical measures to solve metal wear or surface scratch by traditional process (1) Repair welding+processing: this repair method is one of the most traditional methods to solve metal abrasion and scratch, and there are inevitable repair defects in this repair process. a. The welding process produces thermal stress on the metal, which is easy to damage the equipment twice; b. Due to the problem of welding accuracy, it is more difficult to operate the repaired parts after welding in the process of machining or bench worker restoring size; c. Parts repaired by welding are easy to deform and affect the operation accuracy of equipment. (2) Brush plating repair: This process can be used to repair minor defects such as local scratches or surface wear. At the same time, the biggest disadvantage of the brush plating repair process is a. The surface is brushed and plated as a whole, which makes it difficult to operate the local scratches or defects in the middle part, and the repaired part has the problem of delamination or poor combination with the original metal material; B. This repair process can only be used for metal wear with a wear depth of less than 0.3mm, and the scope of repair is greatly limited. Technical Measures to Solve Wear or Surface Scratches of Various Metals by Carbon Nanocoatings The application process of carbon nano polymer materials is very simple and convenient. After the analysis of operating environment parameters, wear or scratches are repaired according to a certain construction process. Common repair processes are as follows: a. Machining repair process: this process uses carbon nano polymer materials to first recover the worn or scratched parts, and uses machining methods to process the dimensions of repair materials to ensure the shape and position tolerance requirements of shaft parts or other parts; b. Component correspondence repair process: the online repair technology of worn parts is completed by using the mutual cooperation of original components during equipment operation. This repair process can ensure the effective mating surface of the two parts to the greatest extent, far exceeding the contact surface between the original metal and metal; c. Tooling and mold repair process: make corresponding repair tooling according to the original design drawing size of parts or the actual size measured on site, and complete the repair of worn parts in combination with the application characteristics of carbon nano repair materials, which can well ensure the shape and position tolerance requirements of shaft parts. The industrial carbon nano polymer repair technology is similar to a cold welding technology. Its advantages are that it has excellent compression resistance, corrosion resistance and thermal alternation resistance, as well as high chemical stability and good physical and mechanical properties. It can firmly adhere to the metal surface without falling off easily. The online repair process will not produce high temperature, which will protect the equipment body from damage and will not be limited by wear during the repair process.

The main processes of precision machining include soft machining, hard machining and electric machining. How to choose the appropriate processing technology? Now, our engineers from Nuoba will give you a detailed introduction: When the die is large and deep, soft machining is used for rough machining and semi finish machining before quenching, and hard machining is used for finish machining after quenching; Small and shallow moulds can be milled once after quenching. If the mold wall is very thin and the mold cavity is very deep, electric machining is used. If the mold cavity has a large and flat bottom, the integrated milling cutter head is used for rough machining, and then the round nose milling cutter is used for angle cleaning. The cutting force and heat dissipation effect of the integrated milling cutter head are very good. The round nose milling cutter is more efficient than the flat end cutter in processing the parts requiring back chipping, and is not easy to break the edge.  

In the machining of mechanical parts, the workpiece will be affected by cutting force and cutting heat, which will change the physical and mechanical properties of the surface layer metal. In the process of grinding, plastic deformation and cutting heat will be more serious than cutting edge. In order to ensure the mechanical properties of machined surfaces of parts, we need to know what factors affect the mechanical properties of machined surfaces of parts. 1. Cold work hardening and evaluation parameters (1) Cold work hardening of metals In the process of machining, due to the role of cutting force, plastic deformation is very easy to occur, which makes the lattice distorted, distorted, and even broken. These will improve the hardness and strength of the surface metal, which is called cold work hardening. (2) Main factors affecting cold work hardening ·With the increase of the blunt radius of the cutting edge, the extrusion effect on the surface metal will be enhanced, which will aggravate the plastic deformation and lead to the strengthening of the cold hardness. ·The wear of the rear tool face increases, and the friction fixture between the rear tool face and the machined surface increases the plastic deformation, leading to the hardening. ·The influence of blunt radius of cutting edge on work hardening cutting speed increases, the interaction time between tool and workpiece shortens, so that the extension depth of plastic deformation decreases, and the depth of hardened layer decreases. When the cutting speed is increased, the action time of the cutting heat on the workpiece surface is shortened, resulting in the hardening. 2. Change of metallographic structure of surface layer material (1) Grinding burn: when the temperature of the grinding workpiece surface reaches above the phase change temperature, the surface metal will undergo metallographic changes, which will reduce the strength and hardness of the surface metal, resulting in residual stress and slight cracks. Tempering burns, quenching burns and annealing burns may occur during grinding of quenched steel. ·Tempering burn: the temperature in the grinding area does not exceed the transformation temperature of the quenched steel, but has exceeded the transformation temperature of the rough body. The tempering martensite structure of the surface metal of the workpiece will be transformed into the tempering structure with low hardness. ·Quenching burn: If the temperature of the cutting area exceeds the phase change temperature, coupled with the role of the coolant quenching, the surface metal will undergo secondary quenching, and its hardness will be higher than that of the tempered martensite, while the lower layer of it will cool slowly, and a tempering fabric with a hardness lower than that of the original tempered martensite will appear. ·Annealing burn: If the temperature of the cutting area exceeds the phase change temperature, and there is no coolant entering the grinding area, the surface metal will produce a return structure, causing a sharp drop in surface hardness. (2) Residual stress of surface layer: under the action of cutting force, the machined surface will be affected by tensile stress, resulting in elongation plastic deformation. When the surface area tends to increase, the inner layer will be in elastic deformation. When the cutting force is removed, the inner metal tends to recover, but it cannot return to its original shape due to the limitation of the plastic deformation of the surface layer. Therefore, there will be residual compressive stress on the surface layer and tensile stress on the inner layer.

Hardware surface treatment is a process to artificially form a surface layer on the surface of the base material that is different from the mechanical, physical and chemical properties of the base material. The purpose of surface treatment is to meet the requirements of corrosion resistance, wear resistance, decoration or other special functions of products. For metal castings, we usually use mechanical grinding, chemical treatment, surface heat treatment, and spraying surface treatment. Surface treatment is to clean, clean, deburr, remove oil stains, and scale on the workpiece surface. 1. Manual processing Such as scraper, wire brush or grinding wheel. Rust and oxide skin on the surface of workpiece can be removed manually, but manual treatment is characterized by high labor intensity, low production efficiency, poor quality and incomplete cleaning. 2. Chemical treatment It mainly uses acidic or alkaline solutions to react with oxides and oil stains on the surface of the workpiece, so that they can be dissolved in acidic or alkaline solutions, so as to remove rust, oxide skin and oil stains on the surface of the workpiece. It can be achieved by cleaning with nylon brush rolls or 304 # stainless steel wire (steel wire brush rolls made of acid and alkali resistant solutions). Chemical treatment is suitable for cleaning thin plates. 3. Mechanical treatment It mainly includes wire brush roll polishing method, shot blasting method and shot blasting method. Polishing method means that the brush roller, driven by the motor, rotates at high speed on the upper and lower surfaces of the strip in the opposite direction to the movement of the rolled piece to remove the scale. The brushed iron oxide scale shall be flushed out with a closed circulating cooling water flushing system. Shot blasting cleaning is a method that uses centrifugal force to accelerate the shot to the workpiece for rust removal and cleaning. However, due to the poor flexibility of shot blasting and the limitation of the site, there is some blindness in cleaning the workpiece, and it is easy to produce dead corners on the inner surface of the workpiece that cannot be cleaned. The equipment structure is complex, and there are many vulnerable parts, especially the blades and other parts, which wear quickly, have many maintenance hours, high costs, and large one-time investment. The surface is treated by shot peening, which has great impact and obvious cleaning effect. However, the processing of shot peening on thin sheet workpiece is easy to deform the workpiece, and the steel shot strikes the workpiece surface (no matter shot blasting or shot peening), which will deform the metal substrate. Since Fe3O4 and Fe2O3 have no plasticity, they will peel after being broken, and the oil film will deform with its material, so shot blasting and shot peening cannot completely remove the oil stain on the workpiece with oil stain. Among the existing surface treatment methods for workpieces, the best cleaning effect is sand blasting. Sand blasting is applicable to the cleaning of workpiece surface with high requirements. However, the current general sand blasting equipment in our country is mostly composed of original heavy sand conveying machinery such as hinge, scraper, and No. 1 elevator. The user needs to build a deep pit and make a waterproof layer to install machinery. The construction cost is high, the maintenance workload and maintenance cost are huge, and a large amount of silica dust generated in the sand blasting process cannot be removed, which seriously affects the health of operators and pollutes the environment. The sand suction machine is often used as a sand conveying machine in foreign countries. In fact, the sand suction machine is a super large vacuum cleaner, which connects the hopper with the sand suction machine by using a thick conveying pipe to suck the sand into the storage tank. The characteristics of the sand suction machine are that the construction difficulty and technology are simpler than the bucket elevator, and it is easy to control and requires less maintenance. However, the power consumption is large. At present, there are several domestic manufacturers specializing in making sand suction machines, However, the technology is relatively immature, so most surface treatment enterprises mainly use bucket elevators. When selecting sand conveying equipment and dust removal equipment, factories that need shot blasting process must take full account of the actual production situation, and try to select equipment with higher power than that required for production. Since equipment in shot blasting industry generally consumes faster, after long-term use, this or that kind of problems will affect production, and selecting equipment with higher power will greatly reduce the time and cost wasted in future maintenance. Insufficient power of dedusting equipment not only damages workers' health, but also seriously affects the visibility of sand blasting room. If the dust cannot be discharged, it also affects the quality of sand itself and the surface roughness of the workpiece. The manual sand blasting room should be designed according to the actual situation, which is relatively spacious compared with the space for containing the workpiece. It should not be too restrained, or it will affect the manual operation of workers. At the same time, the lighting conditions must be good. For dry areas, sand blasting can be carried out outdoors. 4. Plasma treatment Plasma, also known as plasma, is an aggregate composed of positively charged positive particles and negative particles (including positive ions, negative ions, electrons, free radicals and various active groups), in which positive charges and negative charges have equal electric quantities, so it is called plasma, which is the fourth state of matter except solid, liquid and gas states - plasma state. The plasma surface processor is composed of a plasma generator, a gas transmission pipeline, a plasma nozzle and other parts. The plasma generator generates high pressure and high frequency energy to generate low-temperature plasma in the glow discharge activated and controlled in the nozzle steel pipe. The plasmon is sprayed to the workpiece surface with compressed air. When the plasma meets the surface of the treated object, object changes and chemical reactions occur.

CNC milling machine is a kind of automatic processing equipment developed on the basis of general milling machine. Their processing technology is basically the same, and their structures are somewhat similar. CNC milling machines are divided into two categories: without tool magazine and with tool magazine. CNC milling machine is a kind of automatic processing equipment developed on the basis of general milling machine. Their processing technology is basically the same, and their structures are somewhat similar. CNC milling machines are divided into two categories: without tool magazine and with tool magazine. CNC milling machine with tool library is also called machining center. 1. Classification according to tool change form (1) The tool changing device of the machining center of the machining center with the tool magazine manipulator is composed of the tool magazine and the manipulator level, and the tool changing action is completed by the manipulator. (2) Machining center of manipulator The tool change process of this machining center is completed by the tool magazine and the spindle box. (3) Turret magazine type machining centers are generally used in small machining centers, mainly for machining holes. 2. Classification according to machine tool shape (1) Horizontal machining center refers to the machining center whose spindle axis is horizontal. Horizontal machining centers generally have 3-5 motion coordinates. It is common to have three linear motion coordinates (along the X, Y, Z axis direction) plus a rotation coordinate (workbench), which enables the workpiece to be clamped at one time to complete the processing of the other four surfaces except the mounting surface and top surface. The horizontal machining center has a wider application range than the vertical machining center, and is suitable for machining complicated box parts, pump bodies, valve bodies and other parts. However, the horizontal machining center covers a large area and weighs a lot; The structure is complex and the price is high. (2) Vertical machining center refers to the machining center whose spindle axis is vertical. Vertical machining centers generally have three linear motion coordinates, and the workbench has indexing and rotation functions. A horizontal axis CNC turntable can be installed on the workbench to process spiral parts. Vertical machining centers are mostly used to process single cylinder boxes, case covers, plate parts and plane cams. The vertical machining center has the advantages of simple structure, small floor area and low price. (3) The gantry machining center, similar to the gantry milling machine, is suitable for processing large or complex workpieces. (4) Universal machining center Universal machining center is also called five side machining center Small workpiece clamping can complete the processing of all surfaces except the mounting surface; It has the function of vertical and horizontal machining center. There are two common types of Wanjian lying machine centers: one is that the spindle can rotate 900, which can be like a vertical machining center or a horizontal machining center; The other is that the spindle does not change direction, while the worktable rotates 900 with the workpiece to complete the processing of five faces of the workpiece. The installation of workpieces in the universal machining center avoids the installation error caused by secondary clamping, so the efficiency and precision are high, but the structure is complex and the cost is high. Machining centers are usually divided into vertical machining centers and horizontal machining centers according to the state of the spindle in space. Vertical machining centers are those whose spindle is vertical in space, and horizontal machining centers are those whose spindle is horizontal in space. Spindles that can be converted vertically and horizontally are called vertical and horizontal machining centers or five sided machining centers, also known as composite machining centers. Divided by the number of columns of the machining center; There are single column type and double column type (gantry type). According to the number of motion coordinates of the machining center and the number of simultaneously controlled coordinates, there are three axis two linkage, three axis three linkage, four axis three linkage, five axis four linkage, six axis five linkage, etc. Three axis and four axis refer to the number of motion coordinates of the machining center. Linkage refers to the number of motion coordinates that the control system can simultaneously control, so as to realize the position and speed control of the tool relative to the workpiece. According to the number and function of workbenches, there are single worktable machining centers, double worktable machining centers, and multi worktable machining centers. According to the machining accuracy, there are ordinary machining centers and high-precision machining centers. Common machining center, resolution 1 μ m. Maximum feed speed: 15 ～ 25m/min, positioning accuracy: lO μ M or so. High precision machining center with resolution of 0.1 μ m. The maximum feed speed is 15~100m/min, and the positioning accuracy is 2 μ M or so. Between 2 and lO μ M, with ± 5 μ M, which can be called precision level.