In this article, we shall learn about Die Manufacturing process, types of dies, and die materials. We have also provided a PDF for the same.
What is a Die Manufacturing
- In Die Manufacturing, Die is a kind of solid or hollow metal of customized shape that is mainly used in stamping or cutting any shapes or coin, embossing, drawing wires, extruding, press, etc.
- It is a thing that can be customized according to the requirement or necessity. Along with that, anything from simple to complex shapes can be made through a die.
- The dies can be used in the formation process or Die casting process and can be termed as Mould. Die is mainly used in the manufacturing departments of industries. The sections of the die, which are made for forming or cutting, can be made of special metal and hardenable steel and it is also known as Tool steel.
The Various Parts of a Die Set
A common die set used for Die Manufacturing contains nearly more than 10 different parts, few of which include the following
- Punch Plate
- Die Block
- Blank Punch
- Pierce Pinch
- Dowel pin
- Pierce Punch
- Stripper Plate
Parts of a Stamping Die Manufacturing
Stamping dies used for Die Manufacturing have several components which are as follows
- Die Sets, Die Plates and Shoes
- Bushings and Guide Pins
- Heel Plates and Heel Blocks
- Screws, Keys, and Dowels
- Stripper Pads
- Pressure Pads
- Draw Pads
- Spools, Keepers and Shoulder Bolts
Die Sets, Die Plates and Shoes
Die Plates, Die Sets, and Shoes are made of either aluminum plates or steel plates. In a critical tolerance, these parts are flat or parallel. So they can be grounded or machined-milled. Of these all, the popular one is grinding. So that as a ground surface, the milled surface also should be accurate.
The die set can be created by attaching lower die shoes and upper die shoes with guide pins. The lower shoe of the die contains holes, that are made by flame-cut. These holes help to create scrap and slugs as the die can freely fall on the press. These holes also help as in the clearance of other components as gas springs.
Bushings and Guide Pins
Guide pins are used as guideposts. Guide bushings are used with guide pins to align lower and upper shoes together. Guide pins and guide bushings are the components of precision ground. They are made of 0.0001 in. To install the components in the method of numerous specialty, mounting can be used. Two types of bushings and guide pins are present.
They are Ball bearing-style pins and friction pins. Guide bushings are slightly bigger in inside diameter than the pins as they are precision-ground pins. Bushings are made of a special wear-resistant material known as aluminum-bronze and the guide pins are made of hardenable steel. As aluminum bronze contains graphite, it reduces friction.
Heel Plates and Heel Blocks
A special kind of steel block is a heal block. Heal block is screwed, precision-machined, welded, and dowelled to lower and upper shoes. At the time of forming process and cutting, side thrust generates. This thrust is then absorbed by the wear plates and the functional components. The one-directional force may deflect the pins, which can be the cause of misalignment at forming or cutting. So it is necessary to observe whether any one-directional force occurred or not.
Heel blocks are mostly made of steel heel plates. In the opposite shoe, there is a wear plate that is made of some dissimilar metals like aluminum-bronze. Heat, cold welding, or galling occurs because of the friction made by the same metal in two opposite plates. As in all directions, the die has a heel, and box heel blocks are to be used. In another hand, to heel any or all directions, heel blocks are used.
Screws, Keys, and Dowels
Screws secure and fasten the components which are working in both lower and upper shoes. In stamping dies the fastener is the cap screw socket head. In Milled pockets of die shoes, the key, a rectangular, small block, can be inserted. Keys the heel and locate the components and the sections of the die. Dowels are used to locate the proper location of the die section and die shoes. Dowels are usually precision-ground, hardened pins.
At the time of forming and cutting process the pads, flat, pressure-loaded plates, are used to control and hold the metals. According to the functions, pads are made from either hardenable tool steel or soft low-carbon steel. At the mating section of the die, it must be closely fit with contoured pads. In stamping dies, there are different types of pads. They are as follows:
At the cutting punches, a stripper pad is used to strip or pull the metals. Stripper pads are usually spring-loaded and flat. When it is cut, the metal is used to collapse on the shank or body. The stripper pads are used to mount the die shoes, mainly the upper shoe.
Before the contact of forming punch with the metal, in the lower section of the die, the metal has to be taken down. It is done at the time of the wipe-bending process. The amount of bending force and the force pressure pad should be equivalent.
On the sheets of metals, the amount of downward force and pressure is exerted. This determines how much flow in the metal can be agreed upon and the die cavity by drawing can enter. According to that, flow in metals can be controlled by the draw pads.
Spools, Keepers and Shoulder Bolts
The shoes die used to move from up to down. The Spools, Keepers, and Shoulder Bolts are used as the fasteners of this movement. By screw or dowels, Spools, Keepers, and Shoulder Bolts are secured with lower and upper die shoes.
The retainer can be used to secure the components with lower and upper die shoes at the time of forming and cutting process. The popular retainer among all is a ball-lock retainer. It is a high-precision retainer. It is used to align and secure the forming and cutting punches accurately.
It uses a spring-loaded ball-bearing. In the teardrop shape, the spring-loaded ball bearings are locked not to come out of the punches. This ball-lock retainer gives advantages to the technicians to reinstall the punches by removing them quickly. It is a ball-lock retainer’s advantage.
Spring is a component that can be used to supply force to the strip, form metal, and hold it. Different springs can be used here. The most popular springs are gas springs, coil, and urethane springs.
Gas springs are filled with nitrogen. It helps by giving a good amount of force. A coil spring is used, when there is a need for the force of a reasonable amount. Urethane spring is worked at short-run stamping. These Coil and Urethane springs are also known as Marshmallow springs.
Types of Stamping Die Manufacturing Techniques
In Die Manufacturing, According to the use in the operation of sheet metal, die are of six types which are as follows
- Simple Die
- Combination Die
- Compound Die
- Progressive Die
- Transfer Die
- Multiple Die
The simple die is that die where at one stage, one operation can be done by one stroke.
Advantages of Simple Die
- It is the simplest form of the die.
- It is one stroked die.
The Combination die is a die where at one stage, multiple forming and cutting operations can be done in one stroke. Such examples of combination die are as following
- Combined deep drawing and blanking
- Combined deep drawing and punching
- Combined bending and blanking
Advantages of Combination Die
- Productivity is too high as the operation is done as a combination of forming and cutting.
The compound die is that die where at a stage, multiple operations can be done by one stroke.
Advantages of Compound Die
- Multiple components are produced in one stroke.
- Productivity is high.
Limitations of Compound Die
- The required force is high.
- No usability of punch forces reducing methods.
- Difficult manufacturing and design of the combination of die and punch, for greater than 3 operations.
Multiple operations of cutting can be performed in a stroke in Progressive die. But blanking is the last operation as different punch sheets and stages are progressing to complete the operation of punching from one to another stage.
Advantage Progressive Die
- By one stroke, multiple components can be produced.
- Productivity is the same as the compound die.
- Force is reduced by providing staggering or shear.
- Manufacturing and design of the combination of die and punch are easier.
Limitations of Progressive Die
- Force balancing is difficult.
- Precision alignment and setup procedure is required.
- Much heavier than single die.
Transfer die is that die which is the same as the progressive die. With that here, the first operation is the blanking. So that as a first stage, black procedure travels one to another stage and completes the punching.
Advantages of Transfer Die
- Large parts are transferred in more than one presses.
- More economical production than progressive die.
- More versatile.
Limitations of Transfer Die
- More costly.
- In each stage, has to set the blank.
- More sensor for protection of die is necessary.
More dies attached parallelly to produce more components are known as Multiple Die.
Advantages of Multiple Die
- Productivity is High.
- In the existence of more than one dies, more products can be produced.
- It consumes less time.
Materials of Die Manufacturing
To make a die, so many materials are needed to be present. These contain so many steels of different kinds and the material of non-metallic and the casting of non-ferrous metals and ferrous metals
- Carbon Steel
- Carbon Block Steel
- Tungsten Oil Hardening Steel
- High-Alloy Oil-Hardening Steel
- Manganese Air Hardening Steel
- Chromium Air Hardening Steel
- High Alloy Air-Hardening Steels
Manganese 0.20 to 0.45, Carbon 0.90 to 1.15, Sulphur 0.025, Phosphorus 0.025, and Silicon 0.16 are present in this Carbon steel.
Carbon Block Steel
Carbon Block Steel contains manganese 0.50 to 0.70, carbon 0.55 to 0.65, chromium 0.60 to 1.10, and nickel 1.25 to 1.75.
Tungsten Oil Hardening Steel
This Tungsten Oil Hardening Steel contains manganese 0.25, tungsten 1.75, and carbon 1.20.
High-Alloy Oil-Hardening Steel
This High-Alloy Oil-Hardening Steel is non-deforming in nature. It contains about chromium 12.00, carbons 2.15, and manganese 0.35. Other elements, Tungsten, Nickel, and Vanadium can add to this steel.
Manganese Air Hardening Steel
This Manganese Air Hardening Steel contains manganese 2.5, carbon 0.90, molybdenum 1.00, chromium 1.5, and silicon 0.30.
Chromium Air Hardening Steel
This Chromium Air Hardening Steel contains chromium 5.00, carbon 1.00, manganese 0.50, molybdenum 1.00, silicon 0.25, and sometimes vanadium 0.50 can be added.
High Alloy Air-Hardening Steels
This High Alloy Air-Hardening steel is as same as the High-Alloy Oil-Hardening Steel. It contains chromium 12.00. The carbon varies between 1.00 to 2.15, molybdenum 0.80, silicon 0.35, manganese 0.35 and sometimes vanadium 0.50 can be added too.
Materials for Producing Low-Cost Die
In the aircraft manufacturing process as well as in some other cases o die manufacturing a die needs to be developed by a die maker through different materials that can be a better choice rather than using some cast steels or steels. Although, a die maker needs enormous practice and skill to do the same thing. This type of scenario occurs during the die-making that related to aircraft manufacturing to reduce the material utilization cost.
Apart from that, it is also true that the quality of metal that is produced through magnesium or aluminum may not be up to the mark as compared to the quality of cast steel or steel. Generally, the materials taken into account by a die maker to make a die are Cerrobend, and Kirksite, which are non-ferrous materials in nature. On the other hand, non-metallic materials such as Bakelite, plastics, Masonite and different kind of wood are also can be utilized to make a die. Moreover, these materials are going through the stretch-forming process to make a die.
Die Manufacturing Process
- First of all, the die shop within a mechanical workshop has to ensure that every die maker should be properly trained as well as aware of the fact through which a die can be developed.
- In this era of modernization, in most cases, every die maker creates a design in AutoCAD and tests that through a prototype tool. Apart from that, the processes that should be incorporated with the die-making process are discussed below briefly.
- The die maker imports the design from the database and checks the precision of the drawing. In the next step, the die maker counts the time through a blank design and determines the phases of completion. Such as the width of a strip distance between pitch, angle, and so on.
- Now it becomes a fact that most companies compare the drawing with a standard drawing through the visualization process.
- The next step is developing the shapes according to the requirements.
- In regards to this finite element analysis, should be carried out by the die maker to analyze the draft angles, and safety zones as well as the other calculations. In the other step, errors are encountered by the die maker. Henceforth, the layout is made and developed in a free form shape.
- ECO or Engineering Change Order can be utilized to design the tool. After that, a template should be created according to the standard deviation.
- Then in the next step, the die maker deals with the making process of the prototype tool. In this case, Cimatron’s NC is used regarding the same.
- Through this NC, the set up of a high-quality die can be developed and its precision can be secured appropriately by the die maker.
Difference Between Die and tool
|Definition||A die is a special tool used to shape or cut materials into required dimensions.||A tool is any device used to do a particular job at hand.|
|Function||A die is used to form materials like metals, plastics, and composites into specific dimensions||A tool can be used for various operations like cutting, drilling, shaping, measuring etc.|
|Types||Different types of dies are used to perform tasks, like stamping, extrusion, or forging.||Different types of tools are used for performing tasks, like cutting, drilling, or measuring.|
|Materials||Dies are typically made from hard and robust materials like steel, carbide, or diamond.||Tools can be manufactured from materials like steel, high-speed steel, ceramics.|
|Manufacturing process||Dies are made using special techniques like forging, casting, machining, or electrical discharge machining (EDM).||Tools are made using various techniques like forging, casting, machining, or grinding.|
|Cost||Dies are more expensive in comparison due to specialization operations||Tools vary in price depending on the undertaken task.|
|Lifespan||Dies are designed for longevity without getting replaced in 100 years||Tools Lifespan depends on various factors like usage and maintenance etc|
|Maintenance||Dies need regular maintenance and sharpening for smooth operations||Tools also need regular maintenance, like sharpening or replacing parts, for their proper use|
In conclusion, die manufacturing is a complex process that involves various parts and techniques. The different parts of a die set, including die sets, die plates, shoes, bushings, guide pins, heel plates, screws, and springs, are crucial in ensuring the proper functioning of the die. The choice of materials used for die manufacturing also plays a significant role in the die’s durability and cost.
Different types of die manufacturing techniques, such as simple die, combination die, compound die, progressive die, transfer die, and multiple die, offer various advantages and limitations. Finally, it’s essential to understand the difference between a die and a tool to appreciate their specific roles in the manufacturing industry.