Month: September 2021

Casting bending die aluminum alloy is widely common for the manufacture of shaped castings. For this, pure aluminum or a product obtained as a result of secondary processing of raw materials can be common. The first option is common in the food and chemical industries, suitable for the production of electrical equipment. In general, aluminum accounts for about 20% of all cast alloys.

Features of bending die

When considering the features of this die, it is easy to note that pure aluminum is produced by specialized enterprises and cast into ingots. Secondary metallurgy uses scrap and other non-ferrous metal waste for casting. Thanks to the use of available raw materials, the cost of production also reduces.

If we turn to the statistics data, about half of world enterprises use aluminum bending die scrap. In Western countries, about 90% of all metallurgical plants use recyclable materials. This is due to the fact that recycling not only reduces the cost of production, but also ensures the ecological safety of the environment.

Application area

Due to the high consumer and physicochemical properties of the material, the field of use of aluminum casting is extensive and diverse. The material is inert to almost any environment and has increased corrosion resistance. At the same time, aluminum remains a light, but strong metal, which makes it possible to use it in various industries. Cast aluminum is suitable for the following purposes.

Manufacturing of body parts

For the bending die of such products, aluminum casting alloys are ideal. This is due to the fact that the cost of such products reduces. Considering that many body parts have a complex geometric shape, their production requires the use of milling equipment and appropriate tooling. Casting helps to achieve a similar result.

Parts for shipbuilding and aircraft construction

In this segment of the industry, aluminum is simply irreplaceable. The material is lightweight, so almost all aircraft parts come from it. In shipbuilding, aluminum has found application due to its corrosion resistance and resistance to sea water.

Production of parts with complex geometric shapes

Bending die represented by bodies of revolution and complex linear dimensions are resource-intensive in terms of machining. This requires sophisticated equipment, tooling, and highly qualified personnel. Foundry production is easier and cheaper.

Products for the electrical industry

Among other useful properties, aluminum has a high electrical conductivity. That is why the material is widely common in the manufacture of electrical wiring and other conductive elements. In addition to the above, aluminum has found application in engine building. It has good wear resistance.

 

The use of aluminum casting technologies makes it possible to obtain bending die with the highest possible precision. Moreover, the casting, carried out in compliance with all technological standards and requirements, provides a perfectly flat surface, which reduces the time and financial costs for subsequent processing.

Positive aspects

In conclusion, a number of positive aspects are easy to note. In particular, the cost of producing aluminum is low, especially when compared to other non-ferrous metals common in various industries. It is largely due to this feature that aluminum alloys are widely common for the needs of various enterprises.

In addition, the popularity of aluminum is due to the high performance properties of the material. It is a lightweight and durable bending die that can be common in any environment, including aggressive ones. That is why aluminum alloys are in demand in various industries.

What is pressing?

Pressing is one of the main methods of industrial processing of materials. The essence of the technological process is to increase the density of the feedstock and give the desired shape to the products. In addition, when performing such operations, the individual work pieces combine into a single product. Metal or composite materials can be common as raw materials.

How does metal pressing take place?

Metal pressing takes place by squeezing it out of a closed contour through a hole in the matrix. Composite materials are pressed in confined spaces by external compression. For this, molds are common, structurally consisting of a matrix and two punches

General Provisions

The manufacturing and engineering industries require a large number of high-precision tools as bending die. Moreover, such products should not only be accurate, but also easy to use, durable and as cheap as possible to manufacture. It is these tasks that determine the requirements for the materials common in tool making. The following types of steels are best for these purposes:

• Carbonaceous of ordinary quality
• Structural
• Instrumental

For which purpose tool steel is common?

Tool steel is common in the manufacture of measuring and cutting tools, individual assemblies of industrial molds and dies. It should be clarified that in the manufacture of cutting tools, such steel is not the only material. It also uses metal-ceramic plates and alloys, diamonds, etc.

Are other materials can be common with steel?

In the manufacture of bending die, it also allows to use other materials that are less durable than steel. The most common of these is gypsum. The dry mixture dilutes with water and stirred until a homogeneous mass obtains. The optimal consistency resembles thick sour cream.

The resulting mixture is poured into metal boxes, the lid and bottom of which are usually come in a removable version. For the manufacture of copier models, it allows to use wood, wax and other materials. In any case, the inner surfaces are carefully processed, all defects are eliminated.

Materials for making bending die depending on the pressing method

There are several ways to implement these technological processes. In the West, this technique was originally common to make parts of complex geometric shapes and precision forging metal ingots. The process is energy-consuming, but it provides the maximum production speed.

In fact, here we are talking about diffusion welding of raw materials heated to high temperatures using short-term external compression.

Production methodology

Considering the production methodology, bending die with heat-insulating coatings is common here. The main disadvantage of such molds is the high production cost. In addition, continuous operation at elevated temperatures leads to rapid destruction of working surfaces. The coatings have to change, which negatively affects the speed of the foundry.

Rules for the operation and maintenance of stamp tools

Correct use and customer service of the stamp tool is very important to keep the tool in good working order for a long time, while reducing your tool costs. The increase in tool life depends on the following factors:

• Applying the correct die gap in accordance with the type and thickness of the material
• The alignment of the tool in the turret and the serviceability of the seats in the revolver
• Application of various types of protective coatings for tools
• Regular sharpening of the tool according to the specified recommendations
• When stamping a large number of identical holes, it is necessary to use two tools
• Lubricate the sheet
• Ensure automatic supply of lubricant to the tool

 

Tool alignment in the revolver

Revolver adjustment is a procedure that can help prevent a sharp decline in stamp tool life, product quality and prevent wear of the revolver. It is recommended to periodically inspect the alignment of the stations in the revolver. The alignment check is carried out using a special alignment tool.

The adjustment carries out in accordance with the service instructions for this type of equipment. It is also necessary to check the condition of the tool guide.

Application of a protective coating for punches

Exacta Precision is one of the leading companies in the heat treatment and surface treatment of tools and accessories. The company was one of the first to introduce ion-nitride, cryogenic treatment and now offers a full range of surface coating treatments. All Thick stamp tool guides are vacuum hardened, nitrided to harden the surface layer and resist abrasion, fatigue and corrosion.

Ø The titanium carbonitride

The titanium carbonitride (TiCN) coating is silver to bronze in color. The thickness of the coating layer is 2-5 microns. The achievable hardness of the coating is 66-70 HRc with high abrasion resistance. Whether you need to stamp abrasive or heavy-duty steels, titanium carbonitride coating is your choice.

Ø Chromium nitride (CrN) coating

It is usually silver in color with a hardness of 62-64 HRc. The thickness of the coating layer is 2-5 microns with increased adhesion. This property makes this coating indispensable for drawing or stitching operations.

Lubrication of the processed sheet and stamp tool

Practical experience with the stamp tool confirms that the lubrication of the surface of the sheet increases the life of the tool. For this purpose, a variety of punching, stamping and cutting lubricants have been developed. In turn, the lubrication of the tool itself also increases its resistance to wear.

The oil film creates a protective layer on the working part of the punch and reduces the adhesion of particles of the processed material to the punch. Punches without a lubrication system are recommended for use with graphite or molybdenum based lubricants. The rubbing surfaces between the guide and the tool holder in the revolver are lubricated with liquid oil.

Use of pads in stamp tools

Shims can be common to increase the stamp tool life - dies of all stations and punches. Shims are common after regrinding of punches and dies. Punch shims provide the required length of the punch assembly after sharpening. Die shims provide the necessary penetration of the punch into the die and exclude sheet deformation.

 

Spacers should be made of steels with increased hardness and thickness accuracy. The use of warped shims can result in misalignment of the tool, reduced tool life, or destruction of the die holder.

Use of punch sleeve

The use of a special punch sleeve in the A and B stations of the Original style during its reversal provides an increase in the size. For C and D stations, the use of shims increases the possibility of punch re-sharpening up to 4 mm. But you need to be very careful, because exceeding this size of shims can disengage the punch from the dowel key and cause damage to both the stamp tool and the machine.

Feature of processing thick materials

When processing thick steel plates with a thickness of more than 3.0 mm and stainless steel with a thickness of more than 2.0 mm, the following recommendations must be adhered to:

• Use a punch with a large reverse angle - up to 1 °
• Minimum punch size 6.40 mm
• Moreover, radius at the edges of the punch not less than 0.5 mm
• Obligatory sheet and tool lubrication
• Processing is carried out at a reduced speed

Stamping force

Observe the required stamping force. The stamping force should not exceed 80% of the maximum press force. Important: when stamping with stations C, D and E, the spring compression can be common from 10% to 20% of the press force.

Use stations A and B of Heavy Duty type

We recommend stamping using the bridging method - this contributes to an even load on the punch. One-sided stamping is not recommended if less than 70% of the punch length is involved.

Cluster stamp tool processing

Processing with a cluster stamp tool can significantly reduce the processing time of a perforated sheet, with a higher quality than processing with a single tool. When processing with a cluster tool, the total number of strikes on the sheet is reduced.

Why re-punching the holes are not good?

Do not re-punch the holes with a cluster on existing holes, because doing so will skew the tool and possibly damage it. If the multiplicity of the rows of the cluster does not allow performing the entire perforation without re-punching, then it is necessary to finish the processing with a single tool.

Using die casting often no further machining is important after molding. It has accuracy of 99.8%, but die cast products is also good to use raw. They still have an aesthetically pleasing finish. Of the zinc common in the world, about 28% is good in the automotive industry.

Summary stamp tool

Zinc has become one of the most important metals in stamp tool industry, especially for products such as:

• lock housings
• pawls
• retractors and pulleys in seat belt systems components.

By using this metal and its alloys, it is possible to achieve a strength, ductility and malleability impossible to obtain with other materials.

Injection molding and vacuum forming tools are two very popular processes for making plastic parts. This article explains the capabilities of both processes and provides general guidance on the types of products for which a particular process is most appropriate. First, a quick overview of how the processes work:

What is injection molding?

Injection molding is a method of making plastic parts by melting plastic and injecting it into a molding tool.

What is vacuum forming tools?

Vacuum forming tools is a method of forming plastic parts by stretching a heated sheet of plastic over a vacuum forming tool. Technological capabilities

Technological capabilities

Injection molding produces parts with incredible detail, while micro-sized parts can still have ribs, projections, metal inserts, side rods, threads, holes, and more. Since the plastic is injected into the inside of the mold, the product can have almost any shape.

Results depend on the correct design and manufacture of the tool that forms the part, the correct choice of material, and the correct use of the injection molding machine.

Shaping of the forming tools

Vacuum forming is not as versatile as injection molding. Shaping comes in one direction only, limiting the shape of the part. However, vacuum forming tools allows for much thinner product walls. When a vacuum is generated, parts of the product will always be hollow.

The holes are subsequently cut out with additional machining. With a good tool design, vacuum forming allows complex products and a number of special functions to be obtained.

Accuracy and Tolerances     

Injection molding achieves incredibly tight tolerances, achieving identical products over and over again. Vacuum forming can reach reasonable tolerances, but because the material stretches over or inside the forming tool, it is less controllable than injection molding.

Materials for forming tools

The range of materials for injection molding is huge! There is a huge range of standard materials, as well as things like anti-static plastic, thermoplastic rubber, chemically resistant plastics, infrared, bio-compost and with a color layout or master batch, you also have an endless selection of colors.

For vacuum forming tools, a more limited range of materials is used, but readily available: sheets of ABS, flame retardant ABS, HDPE, HIPS, conductive HDPE, conductive HIPS, PP, PVC, transparent HIPS, and UV stable HIPS & PETG. Various colors and special effects sheets are also available.

Finishing of forming tools

Each injection molding tool has "runners" - channels in the tool through which the molten plastic reaches the core and cavity that forms the product. If the press tool has cold runners, they will bend hard during each forming cycle. They must remove from each molding and easy to reuse.

In shrink fit forming tools, the plastic in the skids remains hot and is common in the next molding, so there is no waste in the production process. In vacuum forming, the actual product always needs to cut from the plastic sheet - this is easy to do by roller cutting, hand cutting, or CNC machining, for example.

RESISTANCE HEATING ELEMENTS

Ø Features of resistance heaters

Electric-type resistance elements are composed of a heat-resistant alloy, be it a nickel-chromium alloy or an iron-chromium-aluminum alloy, usually formed in the form of sinuous zigzags or spirals.

Ø Resistance heaters power

The heating elements are designed to deliver rated power at rated voltage only when hot. If the actual voltage differs from the nominal voltage, the transmitted power will change as the square of the voltage. Remember that a 1% increase in voltage means a 2% increase in power, and conversely, a 1% decrease in voltage means a 2% decrease in power.

Ø Heating coil resistance

The resistance of the forming tools will be lower at room temperature than at hot temperature. The resistance of the heating elements will increase with age due to a decrease in the cross section of the oxidation path and also due to lengthening of the loops. This will result in a reduction in furnace power and permanent failure. This failure is the natural life cycle of the elements.

Ø Environmental exposure

Certain impurities in the atmosphere will destroy the alloy in the elements. These impurities may be present in the incoming gas or release during the operation of the furnace. Cutting fluids are the main sources of impurities, usually carbon and sulfur.

Sulfur, even in small amounts, will cause rapid wear of the heating forming tools. In a carburizing atmosphere, the carbon content of the heating element increases, resulting in it becoming brittle and having a lower melting point. Lead, tin or zinc and halides when heated will attack the heating element. These materials must not come into the oven.

Inspection, maintenance and repair of electric heaters

In this article, we will discuss general questions about the use, storage and maintenance of heaters. However, this article is only a reference material. And the actual technical parameters of heaters and equipment should come only after consultation with specialists.

You can ask us a question in the form on the website or call us by phone and detail advice right now.

Heating element connection types

The types of heater leads come by a large number of options. We can divide into several basic types:

• Heat-resistant wires and cables
• Bolts, rods, petals
• Heat resistant connectors
• Ceramic terminal blocks

Heat-resistant wires are the standard connection type for most heating forming tools. Moreover, this includes extruder ring heaters, mold cartridge heaters, and ceramic infrared heaters. To connect the heaters, use only high-quality heat-resistant wires that correspond to the operating temperature of the heater.

For additional protection, high-temperature ceramic and infrared heaters use ceramic bead nickel wire insulation.

Heater coil embrittlement

Some alloys common for the manufacture of heating elements have poor ductility and brittleness. It happens especially after their operation at high temperatures. This is especially true for heaters, which are often common in high-temperature furnaces.

At high temperatures, the wire becomes brittle almost instantly and attempting to move the heater may break. Forming tools are also sensitive to low temperatures. Therefore it is important to bend the heater at a temperature not lower than 22 C.