chengcg – Page 164 – CNC Machining & Turning, Milling, Metal parts

Electroplating process of belt buckle

The hardware BUCKLE needs strong and durable features, so special folding and stamping equipment is needed when molding. How can all kinds of belt buckles be shaped so that each detail can be evenly plated? The understanding of Dongguan bright belt is the plating process of belt buckle.
First of all, we divide the types of electroplating into: rolling and hanging.
1, rolling electricity in the hardware BUCKLE product appearance requirement is not high, its electroplated hardware products will not be very bright, there will be flower marks, of course the electroplating cost is also low. Three pieces of corn, bump, nail, button and bottom button are usually rolling. Hanging up electricity is used on the products which require high appearance of hardware buttons, such as alloy button, Hardware needle button and hardware chain.
If the belt buckle is safe and environmental friendly, it can be divided into nickel plating and nickel free plating.
2, electroplating is to turn color into film by chemical treatment and attach to the surface of the product. If the element of nickel is infiltrated during the electroplating process, it will not conform to the national environmental protection standard, for nickel plating; for electroplating, no nickel is permeated in the electroplating process, that is, nickel free electroplating. Of course, nickel-free plating of hardware products also requires raw materials, such as raw materials itself contains “nickel” that can not be nickel-free plating.
Tips: Hardware accessories commonly used electroplating colors are: bronze, black bronze, red bronze, nickel, dumb nickel, black nickel, light black nickel, dark black nickel, etc. Two. Spray paint (injection). In addition to the deployment of any color, the brightness of the fuel can be distinguished from gloss, semi gloss and dummy oil. Spray transparent oil, commonly known as jet oil, is mainly used for acid protection or surface protection. Wipe the oil and then wipe the surface bulge after spraying.

Five elements of selection of metal hose

1. The nominal diameter of the size hose, the choice of joint type (mainly flange connection, threaded connection, quick connection) and metal hose size, hose length.
2, the pressure according to the actual working pressure of the hose, then query the nominal diameter of the corrugated metal hose and the pressure gauge, decide whether to use a stainless steel tube type of metal hose.
3. The chemical properties of the medium conveyed in the medium hose are determined according to the corrosion resistance parameter table of the material of the hose.
4. The working temperature and range of the medium in the temperature hose; the ambient temperature when the hose works. At high temperature, according to the working pressure temperature correction coefficient of metal hose at high temperature, the pressure after temperature correction should be determined to determine the correct pressure level.
5. According to the state when the hose is used, the optimum length of the correct use and installation of the metal hose and the hose in the settlement compensation, the length calculation of various motion states of the hose, the minimum bending times and the minimum bending radius of the hose, and the correct selection of the length of the soft tube, and the correct installation of the tube.

Surface treatment technology for stainless steel parts

There are many kinds of surface treatment processes for stainless steel, such as electroplating, anodizing, sandblasting, painting, passivation, pickling, degreasing, rust removal and so on. This paper mainly introduces three common surface treatment processes of stainless steel, i.e. passivation, pickling and degreasing.

1. Passivation of stainless steel
The recommended surface of this process must be iron free. The presence of stainless steel particles on the surface of any iron, cast iron, low carbon steel, medium carbon steel or low alloy steel will promote pitting corrosion of “free” iron and stainless steel on its surface. This is a very serious problem, so passivation is used only for stainless steel and stainless steel. The main purpose of stainless steel passivation is to prevent oxidation and corrosion of stainless steel surface.

2. Stainless steel pickling.
The purpose of pickling of stainless steel is to remove the oxide coating on the surface of stainless steel after high temperature welding, heat treatment or hot working. At the same time, steel or iron or steel particulate pollutants corroded by red rust can also be eliminated. Please note that if there is no acid solution to clean the surface after pickling, the surface will soon begin to rust and corrode. The corrosion resistance of the steel surface layer is reduced.
Stainless steel pickling process can be applied to all 200, 300, 400 series of stainless steel surface treatment. All pickling operations result in the removal of impurities from the metal surface with a slight change in size, so the result is a degree of extinction of visual brightness that may also be a significant reduction in size.
Heat treatment in vacuum or a good controlled atmosphere, such as bright annealing, eliminates the need for pickling, which usually results in a better finish for stainless steel.

3. Degreasing and degreasing of stainless steel detergent.
Before any surface treatment of stainless steel, grease, cutting fluid, drawing compounds and other lubricants must be removed before surface heat treatment of stainless steel parts or final passivation treatment. Stainless steel parts must also be further welded before degreasing to prevent carbon from pickup at high temperatures.
Usually, stainless steel cleaning agent is selected. It only needs room temperature soaking for 1-8 minutes to remove any oil stains. It is easy to operate and has low labor intensity. It can be reused repeatedly and the cost of production can be reduced effectively. In cleaning operations with other metals, cleanliness can be increased through the use of brushing, spraying or stirring operations.

Working principle of pulse dust collector in gas box

The dust gas is from the inlet of the dust collector into the air inlet of the bellows (32 series from the ash bucket) into the clapboard to turn to the ash bucket. At the same time, the velocity of the air flow is slow. Because of the inertia effect, the coarse particle dust in the gas falls into the ash bucket, and the fine dust particles enter the filter chamber with the air flow, and the dust is attached to the exterior of the filter bag and the gas after purification. Through the filter bag, we enter the upper cleaning room, which is collected by the cleaning rooms and drained out by the main fan of the dust collecting system and discharged into the atmosphere.
With the continuous filtration process, dust on the surface of the filter bag is increasing and the resistance of airflow is increasing. When a certain resistance value is passed (example 1770Pa), it can be manually operated according to the need, and can also be controlled by an electronic control instrument of the fixed or timing cleaning program, automatically controlling the lifting valve of the first division of the starting dust collector, cutting off the air flow through the filter chamber, and opening the high pressure compressed air released by the electromagnetic pulse valve, and in the first chamber gas box. All filter bags are pulsing and blowing ash (stopping air cleaning) to make every filter bag swollen suddenly, so that the dust accumulated in the bag table will be recovered to the beginning of use, and the dust sink is not applied to the ash bucket. Then the program control instrument opens the lifting valve at the prescribed interval to restore the filter in the first room, and then starts the second room. The lifting valve, closing the filtration air in the second room, opening the electromagnetic pulse valve of the second division room to release the high pressure compressed air, and blowing the dust on all the filter bags in the second compartment box, and clearing the dust on the second chamber filter bag, then the program control instrument opens the second compartment lift valve to restore the filtering of the second division chamber. Since then, according to the pre specified electronic control procedures, the third compartment and the third compartment… The filter bag was stopped by air blowing and ash cleaning until the last compartment cleaned up, and the electric control device was closed, and the dust collector was resumed for official filtration and dust collection. The time interval between the filter and the air blows and the blowing time, the interval between the compartments and the cleaning period are controlled by the program-controlled instrument, and the time is adjustable.

Sintering of powder metallurgy machine parts manufacturing

The sintering process in the production and processing of powder metallurgical machinery parts is one of the most basic processes of powder metallurgy, which plays a decisive role in the physical and mechanical properties of powder metallurgy parts.
Sintering is a kind of high temperature heat treatment, which involves the knowledge of sintering furnace, sintering atmosphere, selection and control of sintering conditions. Therefore, sintering is a very complicated process. At the same time, sintering is a special process of high energy consumption, high equipment investment, and the quality characteristics of the product can not be fully measured. So it is one of the most important links to influence the quality and cost of powder metallurgy parts. The sintering process is very critical and must be strictly controlled to ensure the quality of sintered parts. Therefore, the operators need special skills training to fully understand and master the basic principles of sintering, the process of sintering (such as materials, temperature and time, sintering atmosphere, environment, etc.), the effect of sintering atmosphere, and the factors affecting the quality of the sintered products, so as to master the sintering skills and the skills of sintering skillfully. Improve the ability to analyze problems.
How do the press billets of powder metallurgy be sintered? Sintering is heat treatment of powders or compacts at temperatures below the melting point of major components. The purpose is to make metallurgical bonding between powder particles, even though the powder particles are transformed from mechanical agglutination to grain boundary bonding between atoms.
The purpose of sintering of powder metallurgy parts is that the blank of pressing has the shape and size of the mechanical parts, but its strength is very low, so it can not meet the requirements of use. Before sintering, the blank is only a mixture of powder particle interface, rather than a true atomic binding material. Therefore, sintering must be made to make the billet become metallurgical material and endow the powder metallurgy parts with mechanical and physical properties. The strength and elongation of the iron powder press after sintering are greatly improved. For example, the tensile strength can be increased from zero to 200MPa, and the elongation increase from zero to 8%, if the temperature is 1200 C.
The requirements for pressing and sintering of powder metallurgy machinery parts.
1. precision requirements for size and shape. The size and shape accuracy of sintered parts, including surface roughness, should meet the design requirements. Sintering will cause the sinter to shrink or expand, and the sinter will be deformed because of the uneven distribution of the density of the press and the uneven temperature of the furnace, so the size and shape of the sintered product will change. This requires strict control of sintering conditions to ensure the size and shape accuracy of sintered products.
2. density requirements. In sintering, the density, porosity, porosity and shape of the sintered products change with the sintering of powder particles and the shrinkage or expansion of the sintered products. Relative density and porosity characterize the density of powder metallurgy parts. As a self-lubricating powder metallurgy oil bearing, there is also a requirement for connecting voids.
3. the requirements of the organization. Powder metallurgy parts, like other materials, depend on the structure of the structure, which represent the structure factors of the powder parts: grain size, phase structure, distribution of phase, distribution of alloy components, porosity, pore size and pore shape. The formation and change of the microstructure of powder metallurgy parts mainly occurs in the sintering process.
4. the requirements of mechanical and physical properties. The final sintered parts need to achieve the required mechanical and physical properties. Mechanical properties include strength, hardness, elongation and impact toughness. Physical properties include density, conductivity, thermal conductivity and magnetism.
Sintering of powder metallurgy parts is divided into solid phase sintering and liquid phase sintering. Solid phase sintering is simply a metallurgical bonding between powder metallurgy particles. Liquid phase sintering is the sintering of certain molecular particles in powder metallurgy which produces liquid at higher melting point temperatures. The sintering process of powder metallurgy parts can be divided into pre sintering, grease removal, high temperature sintering and cooling.

Sheet metal processing technology

sheet metal
A kind of processing technology, sheet metal has not yet had a complete definition up to now. According to a definition in a foreign professional journal, it can be defined as: sheet metal is a comprehensive cold processing technology for sheet metal (usually below 6mm), including shearing, punching / cutting / compounding, folding, riveting, splicing, forming (such as car body). The notable feature is the same thickness of the same parts.

Process characteristics
Sheet metal has the characteristics of light weight, high strength, electrical conductivity (able to be used for electromagnetic shielding), low cost, and good mass production performance. It has been widely used in electronic and electrical, communications, automobile industry, medical equipment and other fields. For example, in computer chassis, mobile phone, MP3, sheet metal is an essential part. With the application of sheet metal more and more widely, the design of sheet metal parts becomes a very important part of the process of product development. The mechanical engineers must master the design skills of sheet metal parts skillfully, so that the design of sheet metal not only meets the requirements of the product’s function and appearance, but also makes the stamping die manufacturing simple and low cost.

Main uses
Sheet metal materials suitable for stamping are very numerous. Sheet metal materials widely used in electronic and electrical industry include:

The ordinary cold rolled sheet SPCC SPCC refers to the continuous rolling of steel ingots through the cold rolling mill to make steel sheet or sheet material with required thickness. There is no protection on the surface of the SPCC. The exposure to the air is very easy to be oxidized, especially in the wet environment, the speed of oxidation is accelerated, the dark red rust appears, and the surface should be painted, electroplated, or other protective surfaces.

The bottom material of SECC SECC galvanized steel sheet is a general cold rolled steel coil, which becomes galvanized after the continuous galvanizing line is degreased, pickled, electroplating and various post-processing processes. SECC not only has the mechanical properties and approximate machinability of cold-rolled steel sheets, but also has superior corrosion resistance and decorative appearance. It has great competitiveness and substitution in the market of electronic products, household appliances and furniture. For example, the common use of computer boxes is SECC.

Hot dipped galvanized steel SGCC hot dip galvanized steel coil refers to the semi-finished products of hot rolled or cold rolled, after cleaning and annealing, immersed in the melting zinc groove of about 460 C, and coating the steel sheet with zinc layer, and then made by quenching and tempering and chemical treatment. The SGCC material is harder than the SECC material and has poor ductility (avoiding deep drawing design). The zinc layer is thick and the electric welder is poor.

The SUS301 Cr (chromium) content of stainless steel is lower than that of SUS304, and the corrosion resistance is poor, but after cold processing, it can get good tensile and hardness, good elasticity, more used for spring spring and anti EMI.

Stainless steel SUS304 is one of the most widely used stainless steel, because the steel containing Ni (nickel) is more corrosion resistant and heat-resistant than the steel containing Cr (chromium). It has very good mechanical properties, no heat treatment hardening and no elasticity.

Sheet metal process
In general, the basic equipment includes the Shear Machine, the CNC Punching Machine / laser, the plasma, the water jet cutting machine (Cutting Machine), the bending machine (Bending Machine), the drilling machine and all kinds of auxiliary equipment, such as the uncoiler, the leveler, the deburring machine, the spot welder and so on.

In general, the four most important steps in sheet metal process are scissors, blanking / cutting / folding / rolling, welding, surface treatment, etc.

The sheet metal is sometimes made of gold, which is derived from the English platemetal. In general, some metal sheets are made by hand or die stamping to produce plastic deformation, forming the desired shape and size, and further forming more complex parts by welding or a small amount of mechanical processing, such as the chimneys commonly used in the family, iron. The skin furnace and the shell of the car are all sheet metal parts.

Sheet metal processing is called sheet metal processing. For example, making use of plate to make chimneys, iron buckets, oil tank oil pot, ventilation pipe, big head of elbow, round place, funnel shape and so on. The main working procedure is cutting, bending and buckle edge, bending forming, welding, riveting and so on. It needs certain geometric knowledge.

Sheet metal parts are sheet metal parts, that is, parts that can be processed by stamping, bending, drawing and so on. A general definition is that of parts with constant thickness in the process of processing. The relative is casting, forging, mechanical parts, etc., for example, the iron shell outside the car is a sheet metal piece, no rust. Some of the cabinet made of steel are also sheet metal.

The modern sheet metal process 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 and so on.

The surface treatment of sheet metal parts is also a very important part of sheet metal processing, because it has the function of preventing parts from rusting and beautifying the appearance of products. The surface pretreatment of sheet metal parts is mainly to remove oil pollution, oxide skin, rust and so on. It is prepared for the surface treatment, and then the treatment is mainly spray (roast) paint, spray and rust proof layer and so on.

Advantages and disadvantages of injection molding

The injection is also a machine made shoe, and the help face is ligation on the last of the last. Generally, it is directly injected into the PVC, TPR and other materials by the turntable machine to form the sole, and now there is a PU (chemical name polyurethane) injection molding (machine and mold are not the same as the usual injection).
Advantages: because the machine is made, the output is large, so the price is low.
Disadvantages: if there are many styles, it is more troublesome to change moulds, and the shoe is difficult to set, and it is not cold and sticky.

Material used for forging

Forged materials, in addition to the usual materials, such as carbon and alloy steels of various components, and the next of aluminum, magnesium, copper, titanium and their alloys, are also made by forging or rolling, which are also made by forging or rolling, only because of their relatively narrow plastic zones. So forging difficulty is relatively large, heating temperature of different materials, forging temperature and final forging temperature are strictly required

What is the difference between sheet metal processing and stamping

For the first contact sheet metal processing people, the vast majority of people confuse the concept of sheet metal processing and stamping, although there are many similarities, but there are still certain differences.

First of all, sheet metal processing refers to the processing of sheet metal, which is made of plate made into common items in our daily life, such as chimneys, iron barrels, oil tanks, ventilation pipes, big heads, corners, funnels, etc. it is mainly through cutting, bending, bending, bending, welding and welding. The production technology of the product parts with certain shape, size and performance is obtained by using the power of conventional or special stamping equipment to make the sheet metal directly subjected to deformation force and deformation in the die. Sheet material, mould and equipment are the three elements of stamping process. From the above, it can be seen that stamping is only one of the many processes of sheet metal processing. The relationship between them is included and included, and the relationship between the two can help the employees to make fewer mistakes in the process of later operation and can be mentioned at the same time. The technical level of the high staff in the operation, for the partners who have just joined the sheet metal processing industry, should distinguish the difference between the sheet metal processing and the punching machine, so that it can be more helpful to the future work.
cut off
Cutting is a stamping process to separate materials from the open profile, and the separated material becomes a workpiece or process part.
Expansion
Flaring is a stamping process for expanding hollow parts or tubular parts outwards.
punching
Punching is a stamping process that separates waste from the material or process parts along the closed contour, and obtains the required holes in material or process parts.
Flushing
Blanking is a stamping process that separates waste from material or process parts along an open profile. The gap is formed by an open contour, and its depth is not greater than the width.
Flushing
Punching is a stamping process that separates waste along the open profile from material or process parts. The open profile is grooved and its depth exceeds the width.
Punching center hole
Punching center hole is a stamping process for forming shallow concave center holes on the surface of working parts, and there is no corresponding material on the back material.
Fine flushing
Fine blanking is one kind of bright and clean blanking. It makes use of the fine blanking die with the toothed pressure material plate to make the whole section of the punching piece all or basically clean.
Continuous mode
The progressive die is a die with two or more workstations, and the material is sent to a work station one by one with the stroke of the press.
Single process Die
The single process mold is a stamping die that only completes one process in a stroke of the press.
Combined punch die
The combined punching die is a set of universal and adjustable punching dies which are formed by various geometric elements (straight lines, angles, arcs, holes). The outline of a flat stamping part usually needs several combinations of punching dies.
Protruding
Pressing is a punching process that forces the material into the concave surface to form a protrusion by pressing the punch into the working part.
Embossing
Embossing is a punching process that forces partial crowding materials to form concave patterns, patterns, characters or symbols on the surface of process parts. The surface of the embossed surface does not correspond to a concave convex.
forming
Forming is a general term for stamping processes that rely on material flow instead of material separation to change the shape and size of working parts.
Bright and clean blanking
Smooth blanking is the direct and complete process of blanking the whole section without finishing. Twisting and twisting is a stamping process to twist a part of a straight or partial straight part to a certain angle.
Curling
Crimping is a stamping process that rolls the edges of the process parts into a closed circle. The axis of the rounded circle is in a straight line.
Coiling edge
The roll edge is a stamping process that rolls the upper edge of the hollow part close to the closed circle.
Drawing
Drawing is a stamping process that transforms straight wool or workpiece into curved surface. The surface is mainly formed by extending the material at the bottom of the punch.
Stretch bending
Tension bending is a stamping process under which the bending deformation of the whole bending cross section is subjected to tensile stress under the combined action of tension and bending moment.
Bulging
Bulging is a stamping process that expands hollow parts or tubular parts along the path.
Dissection
Cutting is a stamping process that divides the forming process into several parts.
Leveling
Leveling is a stamping process to improve the flatness of local or integral plane parts.
Undulating forming
Undulate forming is a stamping process that relies on the extension of materials to form part depression or bulge. The change of material thickness in undulate forming is unintentional, that is, a small amount of thickness change is formed naturally during the deformation process, not the design specified requirement.
Bend
Bending is a stamping process using pressure to cause plastic deformation of material and thus be bent to form a certain curvature and a certain angle.
Chisel
Chisel cutting is a process of blanking or punching with a sharp cutting edge. The chisel has no lower die, and the pad underneath the material is only a flat plate, and the most of the impact material is non-metallic.
Deep hole blanking
Deep hole blanking is a punching process with the aperture equal to or smaller than the thickness of the blanking material.
Blanking
Blanking is a stamping process to separate materials from the closed contour. The separated material becomes a workpiece or process part, and most of them are planar.
Necking
Necking is a punching process to reduce the opening of hollow parts or tubular parts.
plastic
Plastic is dependent on material

Working principle of shearing machine

The shearing machine should be able to ensure the straightness and smoothness of the shear surface of the sheared sheet, and minimize the distortion of the sheet to obtain high-quality workpieces. The upper blade of the shearing machine is fixed on the tool carrier, and the lower blade is fixed on the worktable. A supporting ball is installed on the worktable to avoid scratching when the sheet material is slipping on it. The rear stopper is used for the location of the plate, and the position is adjusted by the motor. The press cylinder is used to compress the sheet material to prevent the sheet from moving during shearing. Guardrail is a safety device to prevent accidents. The return generally depends on nitrogen, fast speed, and small impact.
Operating procedures
The first is to conscientiously implement the relevant provisions of the general rules for the operation of forging equipment.
Second: conscientiously implement the following supplementary provisions:
1, carefully before the work:
1) before starting the trial run by air, it is necessary to use the manual turning of a working stroke to confirm the normal operation before starting the equipment.
2) equipment with hydraulic equipment and adequate oil content should be checked. After starting the oil pump, check whether there is leakage in the valves and pipelines, and the pressure should meet the requirements. Open the vent valve to release the air in the system.
2, conscientiously in the work:
1), no shearing and laminates are allowed, trimming the edges of the edges of the rough edges, and cutting the narrow and short materials that are not tightly cut.
2) the gap between the knife plates should be adjusted according to the thickness of the sheet, but not more than the maximum 1/30 of the plate. The knife plate should be fastened and firmly, and the upper and lower cutter surfaces should be kept parallel. After adjusting, the manual barge should be used to avoid accidents.
3) knife edge should be kept sharp. If the edge is blunt or cracked, it should be replaced in time.
4) when shearing, the material pressing device should be firmly pressed against the sheet material, and it is not allowed to cut under the condition that the pressure is not tight.
5), with hydraulic equipment, except for throttling, other hydraulic valves are not allowed to be adjusted.
6) for the thickness of the shear plate of the hydraulic pendulum shear, it should be determined according to the diagram of the relationship between the ultimate strength of the sheet and the thickness of the plate.
3, after work, the upper knife plate should be placed in the lowest position.
Before operation should wear tight protective clothing, cuff fastened, the upper garment can not be open, must not be worn around the machine tool, change clothes, or peri cloth on the body, prevent the machine from wound. Safety helmet must be worn, and plait should be put in the hat, and no skirt or slippers should be worn.
The operator of the shearing machine must be familiar with the main structure, performance and usage of the shearing machine.
The shearing machine is suitable for all kinds of steel plate, copper plate, aluminum plate and nonmetallic material sheet with the thickness of the shear material, and it must be material without hard mark, slag, slag and weld, and it is not allowed to be super thickness.
The using method of the shearing machine: adjust the clearance of the blade according to the thickness of the cut material; adjust the die or fixture according to the width of the cut material; before the operation of the shearing machine, the 1 to 3 air travel is first made, and the shearing work can be carried out before it is normal.
If the operation of the machine is abnormal, the power supply should be cut off immediately.
When the machine is adjusted, the power must be cut off, and the safety of the hand should be paid attention when moving the workpiece.
Every part of the shearing machine should be kept lubricated. The lubricant should be added to the operator every shift. The lubricating oil must be added to the rolling bearing part every half a year by the mechanic.