Machinery industry – Page 10 – CNC Machining & Turning, Milling, Metal parts

Computer gong processing – tapping problem

Drilling, milling and tapping center machine is a kind of machining equipment which has different specifications of through-hole or blind hole in the shell, equipment end face, nut and other tools of CNC machine tool, and the thread, screw or thread are machined on the inner side of parts. Let’s first understand the characteristics of drilling and milling center machine.

The drilling, milling and tapping center machine is very simple when adjusting the model. The automatic reverse device can freely adjust the working stroke of the drilling and milling tapping center machine. The processing workpieces with shallow holes and holes can be easily adjusted. In the double installation device, the screw tap can be prevented from damage, and the spindle can be back and forth and up and down. The double safety clutch is specially designed for the advance and retreat of the cutter. The spindle can stop automatically and the tool will not be damaged by the reversing tool withdrawal. The gear of drilling and milling center machine matches with the pitch between the spindle and the spindle to promote complete matching, vertical stability, accuracy, and high precision. When the screw taps, it can move forward and backward without output. At the same time, it can be configured with multi axis synchronous processing, and the production efficiency will be greatly improved

It can also reduce and save labor: drilling, milling and tapping center machine combines tapping and stamping of parts into a process, which can be fully automated, thus saving labor costs. It can also reduce adverse effects. Accurate positioning of drilling and milling center machine can reduce the damage probability of taps. At the same time, it can also reduce the accurate positioning of drilling and milling center machine, and provide the probability of waste products caused by errors. So what are the common problems in the use of drilling milling tapping center machine? How to solve this problem? Well, today’s editor will help you solve these problems.

Breaking of drill tap

Solutions: when the tap of drilling and milling center machine is broken, the diameter of thread bottom hole should be correctly selected; the drilling depth of grinding edge angle or spiral groove tap should reach the specified standard; the cutting speed should be appropriately reduced and selected according to the standard; when tapping, correct the tap and bottom hole to ensure its coaxiality meet the requirements, and select floating tapping chuck; increase the tap The front angle, shorten the length of the cutting cone; ensure that the hardness of the workpiece meets the requirements, select the safety collet; the anti County tap wear should be replaced in time.

Tap tooth breakage

Solution: tap tooth chipping, properly reduce the tap front angle; appropriately increase the length of the cutting tap; reduce the hardness and replace the tap in time. If the tap is worn too fast, the cutting speed should be reduced properly; the front angle of the tap should be reduced to lengthen the length of the cutting cone; the cutting fluid with good lubricity should be selected; the workpiece to be machined should be properly heat treated; and the tap should be properly sharpened.

Excessive pitch diameter of thread

Solutions: if the pitch diameter of the thread is too large, select the tap pitch diameter with reasonable accuracy level; select the appropriate cutting fluid and reduce the cutting speed appropriately; correct the coaxiality of the tap and the bottom hole of the thread when drilling and milling the tapping center machine, and use the floating chuck; appropriately reduce the front angle and the back angle of the cutting tap; remove the burr generated by the grinding tap and appropriately increase the length of the cutting tap.

Too small pitch diameter of thread

In addition, it is necessary to increase the cutting accuracy of the tap and to select the proper cutting angle of the tap.

The surface roughness of thread is too large

Solution: if the surface roughness value of thread is too large, properly increase the front angle of the tap to reduce the cutting angle; conduct heat treatment to properly improve the hardness of the workpiece to ensure that there is a low surface roughness value on the front cutter surface of the tap; select the cutting fluid with good lubrication; appropriately reduce the cutting speed; replace the worn tap for the drilling and milling center machine.

Drilling, milling and tapping center machine is a kind of metal cutting equipment, of course, it can also drill holes, but from this name, we can see that it is also very aggressive. Well, after a simple understanding of the drilling and milling center machine, the next step is to analyze the current situation of the overall market.

The function of drilling, milling and tapping center machine is to drill the hole and tap together. From here, we can see that one of its characteristics is high efficiency, because it combines the two processes and completes it at one time.

In the absence of drilling and milling tapping center machine, we need to work together with drilling machine, lathe or manual wire drilling tools to complete what it has done now

Difference between fast wire and slow wire in NC WEDM

Fast wire in the professional terminology is called: high speed reciprocating wire EDM wire cutting machine

Slow wire is called low speed unidirectional WEDM in professional terms

The wire speed of reciprocating WEDM is 6-12 m / s. The biggest characteristic of the product is that it has 1.5 degree taper cutting function, and the processing thickness can be more than 1000 mm. It is used in all kinds of medium and low-grade mold manufacturing and special parts processing, and has become one of the most widely used machines in China’s CNC machine tools. However, due to the fact that the reciprocating WEDM machine can not implement constant tension control on the electrode wire, and the computer gong processing, the electrode wire jitters greatly and is easy to break in the process of processing. Because the electric grade wire is used repeatedly, it will cause electrode wire loss, machining accuracy and surface quality reduction.

The electrode wire of low-speed WEDM uses copper wire as tool electrode and generally moves unidirectionally at the speed of less than 0.2m/s. A pulse voltage of 60-300v is applied between the copper wire and the processed materials such as copper, steel or superhard alloy, and a gap of 5-50um is maintained. The gap is filled with insulating medium such as deionized water (close to distilled water), which causes spark discharge between the electrode and the workpiece This is consumed and corroded, and numerous small pits are etched on the surface of the workpiece. Through the monitoring and control of NC control and the execution of servo mechanism, the discharge phenomenon is uniform and consistent during the machining of mechanical parts, so that the processed products can be processed into products with the required size and shape accuracy. At present, the accuracy is up to 0.001mm, and the surface quality is close to the grinding level. The electrode wire is no longer used after discharge, and no resistance anti electrolysis power supply is adopted. Generally, it is equipped with automatic threading and constant tension device. It has the advantages of stable, uniform, small jitter, high machining accuracy and good surface quality, but it is not suitable to process large thickness workpieces. Due to the precise structure of the machine tool, high technology content, high price of the machine tool, the use cost is also high.

It can form plastic parts with deep holes and complex shapes.

Under heat and pressure, the plastic can be heated quickly and evenly through the mold pouring system to ensure short hardening time.

The dimensional accuracy of plastic parts is easy to ensure and the flash of parting surface is thin. It is difficult to extrude plastics with fluidity less than 80mm. The forming pressure is higher than that of the glue pressing method. The consumption of plastic must be increased (pouring part).

Injection method: the granular or powdered plastic is heated and melted into the flowing state in the barrel of the injection machine, and then the whole cavity is filled with a narrow nozzle and the pouring system of the mold with a very high pressure and poor speed. After a certain period of setting, the mold is opened, and the plastic parts can be taken out from the mold. The characteristics of injection molding: short forming cycle, easy to realize. The dimensional accuracy of plastic parts is easy to guarantee.

The mold is usually designed to be fixed. When there are many metal inserts in the plastic parts, the installation of the inserts is more difficult. Plastic mould can be divided into thermosetting plastic pressing mould, thermosetting plastic extruding mould, thermosetting plastic injection mould and thermoplastic injection mould.

According to the form of material cavity, thermosetting plastic pressing mold can be divided into:

(a) Open die, that is, the cavity is the feeding cavity;

(b) Semi closed die, that is, the cross section of the feeding chamber;

(c) The feeding cavity is the continuous part of the cavity, and the forming pressure is completely transmitted to the pressed plastic parts through the upper die.

According to the structure, it can be divided into:

(a) Mobile press mold,

(b) Fixed press mold.

Factors affecting the quality of EDM

There are many factors affecting the processing quality, which are related to the selection of electrode materials, electrode manufacturing, electrode clamping and alignment, the selection of machining standards and the appropriateness of operation process. To prevent the production of waste products, the following should be noted.

Correct selection of electrode materials

In cavity machining, graphite is a common electrode material. However, due to the variety of graphite, not all graphite materials can be used as electrode materials for EDM. Special graphite with high strength, high density and high purity should be used. Copper electrode is often used in precision. One is: the discharge end of EDM, which is used to process cavity, lettering, etc., and is usually made into the required shape. The material is graphite, copper or aluminum (rare). The other is: the discharge end of WEDM is made of molybdenum wire. Its principle is to apply high-frequency and high-voltage to the discharge end through the electric control part. When the electrode (molybdenum wire) contacts with the grounding end (workpiece), it will form high-frequency ignition and generate high temperature, which will quickly dissolve the workpiece surface (a very small gap) in contact with molybdenum wire, which is called wire cutting.

The so-called multi electrode machining refers to the parts to be processed with high precision, and the discharge parts should be discharged twice or more. In the early stage, it is rough discharge machining with larger translation, and the later is fine discharge machining with small translation.

Selection of processing materials for computer gongs

CNC precision machining engineers summarize their experience in actual machining, mainly including the following situations:

The tubular material will bend and deform when it is cut open;
When the center of the part is hollowed by WEDM, the stress and deformation will occur;
POM deforms due to excessive cutting amount or high processing temperature;
Customized materials have not been properly and scientifically aged;
Other complex parts in the process of processing due to improper process settings resulting in subsequent processing deformation;

In order to avoid the deformation caused by the above conditions in the processing, thus affecting the precision of the workpiece, the technical personnel put forward the following countermeasures:

Appropriate and scientific aging treatment should be carried out for customized materials and hollow materials;
The stress effect of each process should be considered in the processing of complex structural parts,

Set up scientific and reasonable process flow;

In the processing of POM and PVC materials, it is necessary to consider the particularity of materials, set appropriate machining allowance, and adopt the principle of “a small number of times” for processing and measuring;
The processing of curved surface needs to design and make good fixture,

Balance the clamping force on the workpiece;

CNC machining center structure can be divided into two parts: host part and control part! The host part includes the body, headstock, worktable, base, column, beam, feed mechanism, tool magazine, tool changer, auxiliary system, etc

The structure of CNC machining center is as follows

CNC machining center structure can be divided into two parts: host part and control part!

The host part includes the body, headstock, worktable, base, column, beam, feed mechanism, tool magazine, tool changer, auxiliary system, etc. the control part includes hardware part and software part

The hardware part includes: computer digital control device (CNC), programmable logic controller (PLC) input and output equipment, spindle drive device, display device, etc.

Software part includes: system program and control program two parts!

The purpose of the automatic tool changer is to meet the processing requirements,

The tool installed on the spindle is automatically replaced. The automatic tool changer is a set of independent and complete parts.

The tool changing process of the automatic tool changing device consists of two parts: tool selection and tool change!

Tool selection means that the tool magazine will automatically move the tool to be used to the tool change position according to the tool selection instruction. Tool change is to take down the used tool on the spindle and install the selected tool on the spindle!

Knowledge of using computer gongs

CNC computer gongs usually use vacuum chuck because the workpiece has high requirements for surface smoothness, or when the fixture of CNC computer gong itself cannot clamp the workpiece well, it is a relatively cheap special fixture in CNC machine tools.

Vacuum chuck used on CNC computer gongs: the vacuum chuck plays the role of fixture in CNC machining center. Some workpieces require high surface smoothness, so they can not use the fixture of common CNC computer gongs. At this time, the vacuum sucker can be put into use. However, we seldom use rubber vacuum cups in CNC computer gongs, but we use CNC vacuum cups more. The so-called CNC vacuum sucker is a kind of special vacuum sucker with vacuum generator and switch. The suction principle is the same as rubber vacuum chuck, which creates a vacuum environment to make the suction cup press on the workpiece under atmospheric pressure, but CNC vacuum chuck is the only one The vacuum environment is produced by the vacuum generator. The rubber vacuum chuck is a simple vacuum component, while the CNC vacuum sucker is like a large plate.

The computer gong machining of CNC machine tools is mainly used to process parts with complex shapes, but the structure of the fixtures used is often not complicated. The selection of fixture for CNC milling machine can be firstly determined according to the batch of production parts. For the single piece, small batch and heavy workload mold processing, the positioning and clamping can be realized directly on the machine table by adjusting, and then the position of the parts can be determined by setting the machining coordinate system.

What is CNC computer gong vacuum sucker: vacuum sucker, also known as vacuum spreader, is one of vacuum equipment actuators. Generally speaking, it is the cheapest way to grab the product with vacuum sucker. There are various types of vacuum suction cups. Rubber suction cups can be operated at high temperature. The suction cups made of silicone rubber are very suitable for grasping products with rough surface, while those made of polyurethane are very durable. In addition, in the actual production, if the sucker is required to have oil resistance, polyurethane, nitrile rubber or polymer containing vinyl can be used to make sucker. Generally, in order to avoid scratches on the surface of the products, it is better to choose the suction cup with bellows made of nitrile rubber or silicone rubber. The material of suction cup is made of nitrile rubber, which has large breaking force, so it is widely used in various vacuum holding equipment.

Machining is a process of changing the overall dimension or performance of the workpiece with processing machinery. According to the temperature state of the workpiece to be processed, it can be divided into cold working and hot working. Generally, it is processed at normal temperature and does not cause chemical or physical changes of the workpiece, which is called cold working. Generally, the processing above or below the normal temperature will cause the chemical or physical phase changes of the workpiece, which is called thermal processing. Cold working can be divided into cutting and pressure machining according to the difference of processing methods. Heat treatment, forging, casting and welding are common in hot working.

The machines needed for machining include digital display milling machine, digital display molding grinder, digital display lathe, EDM machine, universal grinder, machining center, laser welding, middle wire feeding, etc., which can be used for turning, milling, planing and grinding of precision parts. Such machines are good at turning, milling, planing and grinding of precision parts, and can process various irregular shape parts with the machining accuracy of 2 μ M

In addition, cold and heat treatment is often used in assembly. For example, during the assembly of bearing, the inner ring is often cooled in liquid nitrogen to shrink its size, the outer ring is heated properly to enlarge its size, and then it is assembled together. The outer ring of the wheel of the train is also sheathed on the substrate by heating, and the bonding firmness can be ensured when it is cooled (this method is still applied to the transfer process of some parts).

Mechanical processing includes: filament power winding, laser cutting, heavy processing, metal bonding, metal drawing, plasma cutting, precision welding, roll forming, sheet metal bending, die forging, water jet cutting, precision welding, etc.

Computer gong processing – machine failure

Fault analysis is the first step of machine tool maintenance. Through fault analysis, on the one hand, it can quickly find out the cause of the fault and eliminate the fault; at the same time, it can also play a role in preventing the occurrence and expansion of the fault. Generally speaking, the main methods of machine tool fault analysis are as follows:

Conventional analysis method conventional analysis method is a method of routine inspection on the mechanical, electrical, hydraulic and other parts of the machine tool, so as to determine the cause of the failure. On machine tools, conventional analytical methods usually include the following contents:

1) Check whether the specifications of power supply (including voltage, frequency, phase sequence, capacity, etc.) meet the requirements

2) Check whether the connection of CNC servo drive, spindle drive, motor and input / output signal is correct and reliable

3) Check whether the printed circuit board in CNC servo drive device is firmly installed and whether the connection part is loose

4) Check whether the setting end and potentiometer of CNC servo drive and spindle drive are correct

5) Check whether the oil pressure and air pressure of the hydraulic, pneumatic and lubricating parts meet the requirements of the machine tool

6) Check the electrical components and mechanical components for obvious damage, etc

The action analysis method is a method to determine the bad action position by observing and monitoring the actual action of the machine tool and trace the root cause of the fault. Generally speaking, the hydraulic and pneumatic control parts of the machine tool, such as: automatic tool change device, exchange table device, fixture and transmission device, can be determined by action diagnosis.

State analysis method state analysis method is a method to determine the cause of failure by monitoring the working state of the actuator. This method is most widely used in the process of machine tool maintenance. In modern CNC system, the main parameters of servo feed system, spindle drive system and power module can be tested dynamically and statically. These parameters include: input / output voltage, input / output current, given / actual speed, position, actual load condition, etc. In addition, the status of all input / output signals of CNC system, including internal relays and timers, can also be checked by the diagnostic parameters of CNC system. Through the state analysis method, the cause of failure can be quickly found out according to the internal state of the system without instruments and equipment. It is widely used in the process of machine tool maintenance, and the maintenance personnel must master it skillfully.

Operation and programming analysis method operation and programming analysis method is a method to confirm the fault cause through some special operation or compiling special test program section. For example, through manual single step to execute automatic tool change, automatic table exchange action, execute single function processing instructions and other methods to detect the action and function. By this method, the cause and components of the fault can be determined and the correctness of the program can be checked.

Self diagnosis of CNC system is a self diagnosis and testing method for the key hardware and control software of the system by using the internal self diagnosis program or special diagnosis software. It mainly includes boot self diagnosis, online monitoring and offline testing. Adjustment of machine tool accuracy and function,

Using precision level instrument and other detection tools, mainly by adjusting the pad iron way to fine adjust the level of the main bed of the computer gong processing machine tool, so that the geometric accuracy of the machine tool can reach the allowable tolerance range;
For the automatic tool change device, adjust the position of the tool magazine, manipulator, travel parameters, etc., and then check the action with the command, which is required to be accurate;
For the machine tool with APC automatic exchange table, after adjusting the relative position, carry out automatic load exchange;
After the adjustment of the machine tool, carefully check whether the parameter setting values in the numerical control system and the programmable controller conform to the data specified in the random index, and then test the main operation functions, safety measures, execution of common instructions, etc.

Computer gong processing – sheet metal

Purpose of sheet metal:

There are a lot of sheet metal materials suitable for stamping. Sheet metal materials widely used in electronic and electrical industry include:

⒈ the common cold-rolled plate SPCC refers to the continuous rolling of steel ingot into the required thickness of steel coil or sheet. SPCC surface without any protection, exposed to the air is very easy to be oxidized, especially in humid environment, oxidation speed is accelerated, dark red rust appears, the surface should be painted, electroplated or other protection.

The base material of SECC SECC galvanized steel sheet is a common cold-rolled steel coil. After degreasing, pickling, electroplating and various post-treatment processes in the continuous electro galvanizing production line, it becomes the electro galvanized product. SECC not only has the mechanical properties and approximate processability of general cold-rolled steel sheet, but also has superior corrosion resistance and decorative appearance. In the market of electronic products, home appliances and furniture, it is very competitive and replaceable. For example, SECC is widely used in computer cases.
Hot dip galvanized steel sheet SGCC hot-dip galvanized steel coil refers to the semi-finished products after hot-rolled pickling or cold-rolled, which are cleaned and annealed, immersed in the solution zinc bath at about 460 ° C, and the steel sheet is coated with zinc layer, and then quenched, tempered, leveled and chemically treated. SGCC material is harder than SECC material, with poor ductility (avoiding deep drawing design), thicker zinc layer and poor weldability.
The content of Cr (CR) in SUS301 is lower than that in SUS304, and its corrosion resistance is poor. However, after cold working, it can obtain good tensile strength and hardness, and has good elasticity. It is mostly used in spring spring and anti EMI.
Stainless steel SUS304 is one of the most widely used stainless steels. Because it contains Ni (nickel), it is more corrosion-resistant and heat-resistant than the steel containing Cr (CR). It has very good mechanical properties, no heat treatment hardening phenomenon and no elasticity.

2、 Features of sheet metal:

Sheet metal, B ǎ N J ī n (metal plate; Sheet metal in English) has not yet had a relatively complete definition. According to a definition in a foreign professional journal, it can be defined as: sheet metal is a comprehensive cold working process for sheet metal (usually less than 6 mm), including shearing, punching / cutting / compounding, folding, welding, riveting, splicing, forming (such as automobile body), etc. Its remarkable feature is that the thickness of the same part is the same.

Sheet metal has the characteristics of light weight, high strength, conductive (can be used for electromagnetic shielding), low cost, good mass production performance and so on. It has been widely used in the fields of electronic appliances, communication, automobile industry, medical equipment, etc., for example, in computer case, mobile phone, MP3, sheet metal is an essential part. With the application of sheet metal more and more widely, the design of sheet metal has become a very important part in the process of product development. Mechanical engineers must master the design skills of sheet metal parts, so that the designed sheet metal can not only meet the requirements of product function and appearance, but also make the stamping die manufacturing simple and low cost.

Sheet metal processing is the key technology that sheet metal technical staff need to grasp, and it is also an important process of sheet metal forming. Sheet metal processing includes the traditional cutting and blanking, blanking processing, bending and pressing forming and other methods and process parameters, as well as various cold stamping die structures and process parameters, various equipment working principles and operation methods, as well as new stamping technology and new technology. Parts sheet metal processing is called sheet metal processing.

What should we pay attention to when we look at the sheet metal processing plant.

The unfolded drawing of sheet metal processing plant is based on the part drawing

If there are mistakes (similar and asymmetric), it should be highlighted
Reasonable selection of clearance and hemming methods: clearance 0.3 below T = 2.0, 0.5 clearance between T = 2-3, and long edge wrapping with short edge (door panel)
The deployment method should be suitable, convenient, material saving and processability
Burr direction
Draw the sectional view according to the position and direction of tooth extraction, riveting, tearing and bumping
Check the material, plate thickness and plate thickness tolerance
The place to be protected by spraying must be indicated
Enlarge the drawing where the size is large
For special angle, the inner radius of bending angle (generally r = 0.6) should be tested and unfolded
Reasonable consideration of tolerance dimensions: negative difference goes to the end

Formulation of machining process flow

The technological process of machining includes, generally speaking, the process of changing the overall dimension and performance of the workpiece through a kind of mechanical equipment.

The working principle of machining process regulation is high quality, high yield and low cost, that is, under the premise of ensuring product quality, labor productivity can be improved and cost can be reduced as much as possible. What problems should be paid attention to in the process planning? Let’s take a look at it

1., the advanced technology.

When working out the machining process specification, we should make full use of the existing production conditions of the enterprise, adopt the advanced technology and experience at home and abroad as far as possible, and ensure good working conditions.

Economic rationality

Under the specified production program and production batch, there may be several process schemes that can meet the technical requirements of parts. At this time, the process cost is generally required to be the lowest through accounting or comparison with each other.

Precision form grinding technology

Precision form grinding technology, and realize the precision coordinate grinding technology of round hole and mold hole with precision hole spacing. EDM and NC WEDM are widely used, which provide the key processing technology for high hard materials. The specialization, serialization and standardization of die materials are realized. During this period, the high development of mold standardization, the full use of standard parts and components in mold production is not only a major achievement and feature of mold industrial production mode, but also an important technical basis for realizing modern mold production mode. With the progress and development of computer and machine tool industry, die CAD / CAM and CAD / CAM / CAE have become widely used production technologies. They are combined with high standardization to form a modern mold production mode, that is to realize the informatization and digital mold production mode of mold design and manufacturing.

Design: during the period of manual workshop mold making and the early stage of industrial mold manufacturing, mold design was not carried out, and mold manufacturing was completely dependent on the experience and skills of mold makers. With the development of industry, the application of die and mould is becoming more and more extensive, the requirement of mould performance and quality is getting higher and higher, and the production technology is constantly improving. Designing and drawing the die structure system diagram and parts drawing, defining the design requirements and manufacturing technical conditions are the first task and core technology in the mold production process, which has been evolving until now.

However, with the progress of computer and CNC machine tool industry, and the wide application of CNC machine tools such as machining center, the mold design method and method have produced substantial and breakthrough progress. Mold design includes the following three aspects: mold part modeling and structure design, mold structure system design, mold structure parameter calculation and setting. Mold design process and content. The die with high precision needs to be processed by high-precision CNC machine tool, and the die material and forming process have strict requirements, and CAD / CAE / CAM die technology is also needed to design and analyze. Due to the special requirements of some parts, the mold also needs to use advanced technology such as hot runner, gas assisted molding, nitrogen cylinder and so on. The manufacturer shall be equipped with CNC, EDM, WEDM and NC profiling milling equipment, high-precision grinder, high-precision CMM, computer design and relevant software. Generally, large stamping dies (such as automobile cover parts mould) should consider whether the machine tool has blank holder mechanism, or even edge lubricant, multi position progressive, etc. In addition to stamping tonnage, punching times, feeding device, machine tool and die protection device should be considered.

Not every mold manufacturer and manufacturer has the means to master the above mold. When choosing a cooperative manufacturer, we must understand its processing ability, not only depending on the hardware equipment, but also combining the management level, processing experience and technical strength. For the same set of mould, there is sometimes a big gap between quotations from different manufacturers. You should not pay more than the value of the mold, at the same time, should not be less than the cost of the mold. Mold manufacturers like you, to make a reasonable profit in the business. Ordering a set of molds with a much lower price would be the beginning of trouble. Users should start from their own requirements and comprehensively measure. Avoid multi cooperation, try to make mold and product processing one-stop, with qualified mold (test piece qualified), not necessarily can produce a batch of qualified products. This is mainly related to the machine tool selection, forming process (forming temperature, forming time, etc.) and the technical quality of the operator.

Key points of processing cam parts with computer gong

Research on key technology of design and manufacture of continuous fine blanking die for complex parts

The continuous fine blanking die for complex parts is the cutting-edge basic technology of fine blanking technology, which is taken as the leader to carry out the research, hoping to promote the whole fine blanking technology in China. Taking the synchronizer gear ring, clutch plate, longitudinal compound continuous fine blanking process and die as the breakthrough point, the key technology of fine blanking die design and manufacturing is studied, so as to realize the rapid improvement of fine blanking die technology in China and shorten the gap with advanced countries as soon as possible.

Research on life improvement of fine blanking die and related key technologies

Die life is the comprehensive reflection of die material and supporting product level. Taking the fine blanking die life as the leader to carry out technical research can not only solve the problem that the service life of fine blanking die is too low, but also promote the technological development of die material, fine blanking process, supporting tooling and other auxiliary products.

Research and development of composite technology of fine blanking and precision forging

Fine blanking and precision forging are two advanced manufacturing technologies developed in parallel. If the precision stamping part is too thick and needs precision forging, and if the precision forging piece is too thin, it must be fine blanking. The basic idea of developing the composite process of precision forging and fine blanking is to find the combination point of the two processes (such as gear parts with wheel hub and cam parts with short shaft). The precision forging in China has a long history and the level is very high. Therefore, it is a good way to improve the overall level of fine blanking technology in China.

Polishing and grinding of hardware electroplated parts

For hardware electroplated parts, grinding and polishing is a very important step. Polishing technology and polishing effect are directly related to the smoothness, roundness, porosity and brightness of electroplated coatings. Especially for the products with high surface finish, it has strict requirements for the proficiency of polishing machine, grinding wheel, polishing wax, polishing workers and inspectors.

There are polishing lines for plastic electroplated parts, copper parts and aluminum alloy parts. The polishing methods and process details of different electroplating products are very different. It needs to adopt different polishing methods for different product data, different polishing wheels, different polishing wax and wheel rotation speed, so as to obtain high plating product rate and plating layer quality.

Even if it is the same kind of material Hardware electroplating parts polishing, is not the same situation, not the same treatment. There are red copper parts, brass parts, bronze parts, stamping parts, copper casting parts and turning parts. Although they are all copper parts, their polishing methods are different.

For example, the material of the copper stamping parts is generally better, so it is better to polish the surface of the copper stamping parts, The earliest use of 320 mm or 400 mm abrasive belt grinding once, if it is a high demand mirror, then use 600 mm abrasive belt to play once, then use 25 mm hemp wheel to hit diamond white wax, and finally polish with polishing powder. Maybe use soft cloth wheel to hit Japanese white wax or green wax or OK, if it is the demand for high mirror surface, use wool wheel to hit Japanese white wax. Here, pay attention to the soft and hard hemp wheel will directly affect the oil skid of the product.

For the surface polishing of hardware electroplated parts, it is often divided into rough polishing, medium polishing, fine polishing, ultra precision polishing and super mirror polishing. In order to achieve the corresponding surface effect, what type of polishing wheel is selected? What are the characteristics of polishing wax? What kind of process parameters and process flow can be used to obtain the most useful electroplating effect with the lowest polishing cost, which is the main content of electroplated parts polishing technology.

There are many types of manual polishing machine and active polishing machine on the market. Active polishing machines such as disc polishing machine, reciprocating plane linear polishing machine, aluminum plate stainless steel plate double axis polishing machine, pipe polishing machine, etc. At present, there are more advanced active polishing equipment operated by manipulator and robot. In active polishing machine, liquid wax and special polishing wax are usually used for polishing.

The main data of the manual polishing machine are polishing wax and polishing wheel.

According to the abrasives contained in polishing wax, they can be divided into four categories

1, diatomite 2, quartz powder 3, alumina 4, chromium oxide

According to the function of polishing wax, it can be divided into five types: coarse polishing wax, medium polishing wax, fine polishing wax, super polishing wax and super mirror polishing wax.

We also used to use color to distinguish polishing wax, also known as yellow wax, purple wax, green wax, small white wax, etc.

Because of the different sizes and colors, there are no uniform sizes and colors on the market.

For example, stainless steel polishing wax is used to: palmitic acid, stearic acid, rosin adhesive, plus abrasive feldspar powder, corundum, chromium oxide, iron red, etc., and then according to different matrix composition and requirements, different fineness and varieties are made.

Therefore, how to select the appropriate polishing wax is an important step in the polishing and polishing of metal electroplating parts.

In addition to the specifications and dimensions, such as internal and external diameter, thickness, number of layers, maximum speed and rotation direction, the polishing wheels can be divided into the following categories according to their data and shapes:

Cloth wheel

It is made of cotton cloth, white cloth, denim, colored miscellaneous cloth, etc.

The structure shape of cloth wheel includes wave type, fold type, finger type, etc. In addition, there are wind cloth wheel, plane denim cloth wheel, plane color cloth wheel, button cloth wheel, bag cloth wheel and so on.

Hemp wheel

The hemp wheel is made of linen.

Its structural shapes are: plain pure hemp wheel, twill hemp wheel, U-wave hemp wheel, wavy hemp wheel, folded hemp wheel, wind hemp wheel, finger hemp wheel, plane cloth folder hemp wheel, fiber hemp wheel, group nail hemp wheel, etc

Hemp rope wheel

It’s made of hemp rope. There are hemp rope wheel, hemp rope wind wheel, steel core hemp rope wheel, etc.

Nonwoven wheel

Not only cloth wheel is made of different abrasives, man-made fibers and adhesives, but also called nylon wheel. It has nylon wheel, nylon wind wheel, various special-shaped nylon wheel.

At present, there are more businesses using alumina, silicon carbide and other abrasives and a variety of special fibers made of non-woven cloth polishing wheel, this kind of polishing wheel is suitable for the polishing and polishing of various surfaces of objects.