As an important plastic processing method, metal stamping is widely used in automobiles, aerospace, electronics, home appliances and other fields. It uses the up and down impact motion of the punch and the pressing action of the mold to deform the metal sheet under force, thereby obtaining the workpiece of the required shape and size. However, the successful implementation of metal stamping relies on a number of critical design and engineering considerations. This article will explore in detail What are thekey design and engineering considerations for metal stamping? In order to provide reference for engineers and designers in related fields.
1.Material Selection
Inmetal stamping design, the choice of material is considered to be the most important consideration. Therefore, it is important to make a reasonable choice of materials. Various metal materials have their own unique physical and chemical properties, such as ductility, strength, hardness, and corrosion resistance, which have a direct impact on the performance and service life of stamped components. Therefore, how to rationally select materials has become an important issue in the metal processing industry. Commonstamping materials are aluminum, copper, steel,etc., among which steel is the most commonly used material. In some applications, metals have advantages over non-metals, so there is a growing interest in the properties of metals and their impact on the quality and performance of stamping parts. In the process of selecting materials, it is necessary to fully weigh the environment in which the product is used, the performance criteria, the cost factors, and the stamping characteristics of the material. For example, stainless steel is an ideal choice for components that need to withstand high loads and corrosive environments; For those parts that require lightness and high strength, aluminum alloys are particularly suitable.
2.Metal Thickness and Tolerances
The thickness of the metal is considered to be one of the core factors that determine the stamping process and the performance of the part. With the development of the modern automobile industry, higher requirements have been put forward for the strength and stiffness of automobile body materials, and at the same time, people have paid more and more attention to the problem of plate thickness control in the process of metal forming. In stamping operations, thinner sheet metal is prone to wrinkles or breakage, while relatively thick sheet metal has the potential to exacerbate die wear. In addition, due to the anisotropy of the sheet metal and the stress concentration after forming, the local thinning of thesheet metalwill be caused, so that its bearing capacity will be reduced. Therefore, when choosing the right metal thickness, it is necessary to comprehensively consider the shape, scale and usage specifications of the part. In order to ensure the consistency of the part, the setting of tolerances is particularly important. Therefore, it is necessary to design the product with reasonable tolerances during the design phase. The thickness tolerance of a stamped part directly determines the performance of the part and the quality of the final product. If it is too small, it cannot meet the needs of product performance. If tolerances are set too wide, synergies between parts may fail, adversely affecting the assembly and use of the product; For different types of stamping parts, their dimensional accuracy also varies greatly. If the tolerances are too small, then the difficulty and cost of manufacturing will increase. Therefore, in the design and production stage of stamping parts, it is necessary to set appropriate thickness tolerance ranges according to the specific needs of the product and the actual situation of the production process, and implement appropriate measures to ensure the high precision and excellent quality of the parts.
3.Stamping the design
Stamping the designis a core part of the metal stamping process. The design quality of the die directly affects the quality and productioncost of the stamping part. In mold design, there are several key factors to consider:
4.Feature Placement
Inmetal stamping design, the placement of features is also crucial. Features include holes, slots, edges, etc., and their placement will directly affect the stamping process and part strength. When placing features, you need to avoid excessive stress concentrations or deformations during the stamping process. For example, holes should be positioned as far as possible in areas of bending or stretching of the material to reduce the risk of deformation and cracking of the material. The strength requirements of the part also need to be considered. For example, having stiffeners at the edges can improve the strength and stiffness of the part, but too many stiffeners can increase the difficulty and cost of stamping. Therefore, it is necessary to reasonably control the number and position of stiffeners on the premise of meeting the strength requirements.
1.Minimizing Deformation
Advanced mold design technology is used to ensure the accuracy and stiffness of the mold and reduce the deformation of the mold during the stamping process. Reasonable design of the gap of the mold to avoid the material being deformed by excessive extrusion force during the stamping process;Choose metal materials with good ductility and strength to reduce deformation during stamping; Set reasonable stamping speed, edge pressing force and other process parameters to avoid part deformation caused by excessive strain rate; The error compensation method is used to artificially create a new error to offset the original error in the original process system, so as to improve the accuracy of the stamping part.
2.Edge and Corner Treatments
Avoid sharp corner designs and use shapes such as rounded or beveled corners to reduce stress concentration and the risk of rupture in the metal during the stamping process; improve the strength and deformation resistance of the metal by increasing the material thickness at the corners; use appropriate stamping processes, such as stretching andbending, avoid excessive tensile stress or compressive stress at the corners.
3.Stiffening Features
According to the usage requirements of the parts and the actual conditions of the manufacturing process, set appropriate tolerance ranges to ensure the stability and accuracy of the parts; use high-precision measuring tools to measure and inspect stamping parts to ensure that the size and shape accuracy of the parts meet the design Requirements; During the stamping process, the errors of each process are strictly controlled to ensure that the accuracy of each process meets the design requirements, thereby accumulating the final part accuracy.
4.Stiffening Features
Design elements such as stiffeners are added to stamped parts to improve the rigidity and durability of the product. The design of the stiffener needs to consider the fluidity and deformation characteristics of the material to avoid excessive stress concentration and deformation during the stamping process. By optimizing the structural design of the product, the overall strength and stability are improved. For example, reasonable wall thickness distribution, increasing support structure, etc., can be used to improve the rigidity and durability of the product; Heat treatment is carried out on stamping parts, such as quenching, tempering, etc., to improve the hardness and strength of the material, and further ensure the rigidity and durability of the product.
Tool and Die Wear
1. Causes of wear
2. Countermeasures
Springback and Metal Stress
1.Reasons for springback
2.Countermeasures
Complex Shapes and Multi-Step Stamping
1.Challenge
2.Solution
Cost and Efficiency Factors
1.Cost Influencing Factors The cost of mold design and manufacturing accounts for a large proportion, which requires a lot of manpower, material and financial resources.
The choice of material also affects the cost, and the price and processing difficulty of different materials are different.
2.Efficiency influencing factors
3.Optimization measures
1.Metal stamping services
Ourcustom metal stampingand forming services are suitable for multiple industries, including automotive, aerospace, manufacturing and more, to meet the different needs of our customers. Our team has extensive experience and expertise to provide customers with high-quality metal stamping forming services and technical support. Our metal stamping services can provide prototyping solutions for custom metal parts,contact us today to get started on your project.
2.Metal stamping parts production base
Longsheng has a professional teamwith strong skills and rich experience, which can provide customers with professional technical support and after-sales service. We adhere to the principle of “quality first, customer first” and serve our customers wholeheartedly. If you have any processing needs or questions, please feel free to contact us. We look forward to cooperating with you!
1.What is the difference between hot and cold stamping?
The maindifference between hot stamping and cold stampingis the state in which the material is heated before stamping. Hot stamping: Before entering the mold, the steel plate is heated to a high temperature (usually at 880~950°C). Cold stamping: The steel plate is stamped at room temperature without heat treatment. Hot stamping involves heating a billet to the point where it can be formed. Special molds are used to give these blanks the desired shape. The material is then rapidly cooled to lock in the design of the part. This process is best suited for the manufacture of lightweight parts. This process is more expensive than the cold stamping process and does not allow the part to be reformed. Cold stamping does not use heat to form parts, but instead uses strong pressure. Cold stamping is a faster and less costly manufacturing process as compared to hot stamping. It is suitable for a wide range of materials. However, it can cause warping of parts. Hot stamping does not have this problem because it has high tensile strength and stress resistance.
2.How does material thickness impact the stamping process?
Material thickness has a significant impact on the stamping processand finished product quality: ① The thinner the material, the smaller the required mold gap; conversely, the thicker the material, the larger the required gap. Reasonable die clearance is the key factor to ensure the smooth progress of the blanking process. ②The stamping deformation force, discharge force, etc. are directly proportional to the material thickness. The thicker the material, the greater the strength and tonnage of the stamping equipment required. ③ When punching thick sheets, the accuracy is low and the quality is rough. It needs to go through a trimming process to meet the accuracy requirements. Thin sheets may produce surface defects such as wrinkles or strains due to uneven material flow during the stamping process. ④In the bending, drawing and punching processes, the rebound amount of thin materials is usually larger than that of thick materials, so the accuracy of thin material stamping parts may be reduced due to rebound.
3.What are some common challenges in metal stamping and how can they be overcome?
Challenges that may be encountered during the metal stamping process include scrap jam, die wear, unstable stamping part quality, etc. To solve the problem of waste stuck, we can optimize the waste falling path by designing a reasonable waste removal mechanism; perform regular mold maintenance and upkeep to ensure sufficient blanking space on the mold. For the problem of mold wear, we can choose mold materials with good wear resistance to increase the service life of the mold; optimize the stamping process to reduce the friction and impact between the mold and the material. In response to the unstable quality of stamping parts, we need to strictly control the quality of raw materials to ensure the consistency and stability of the materials.Optimize stamping process parameters, such as stamping speed, amount and type of lubricant, etc.
4.How do I choose the right type of metal for my stamping project?
Clarify the requirements for the shape, size, accuracy, surface roughness and strength of the parts; understand the deformation resistance, ductility, conductivity, corrosion resistance and other properties of different metal materials; comprehensively consider the cost of raw materials, mold manufacturing costs, processing costs and production Factors such as efficiency; select appropriate stamping processes and equipment based on the processability of metal materials.
The basicdesign considerations for metal stampinginclude material selection, metal thickness and tolerance, stamping die design, and feature placement; Key engineering challenges include tool wear, springback and metal stress, complex shapes and multi-step stamping, and cost and efficiency factors, all of which are interrelated and affect product quality and productivity. Therefore, when carrying out metal stamping design and engineering, these factors need to be considered comprehensively to ensure the smooth progress of the stamping process and the high-quality output of the product. By continuously optimizing the design and process parameters,metal stamping technologywill continue to contribute to the development of the industrial manufacturing sector in the future.
The content on this page is for reference only.Longshengdoes not make any express or implied representation or warranty as to the accuracy, completeness or validity of the information. No performance parameters, geometric tolerances, specific design features, material quality and type or workmanship should be inferred as to what a third party supplier or manufacturer will deliver through the Longsheng Network. It is the responsibility of the buyerseeking a quote for partsto determine the specific requirements for those parts.Pleasecontact usfor moreinformation.
Metal stamping is a cold-forming process that makes use of dies and stamping presses to transform sheet metal into different shapes. Pieces of flat sheet metal, typically referred to as blanks, is fed into a stamping press that uses a tool and die surface to form the metal into a new shape. Production facilities and metal fabricators offering stamping services will place the material to be stamped between die sections, where the use of pressure will shape and shear the material into the desired final shape for the product or component.
This article describes the metal stamping process and steps, presents the types of stamping presses typically employed, looks at the advantages of stamping compared to other fabrication processes, and explains the different types of stamping operations and their applications.
If you are looking for more details, kindly visit Furui.
Metal stamping, also referred to as pressing, is a low-cost high-speed manufacturing process that can produce a high volume of identical metal components. Stamping operations are suitable for both short or long production runs, and be conducted with other metal forming operations, and may consist of one or more of a series of more specific processes or techniques, such as:
Punching and blanking refer to the use of a die to cut the material into specific forms. In punching operations, a scrap piece of material is removed as the punch enters the die, effectively leaving a hole in the workpiece. Blanking, on the other hand, removes a workpiece from the primary material, making that removed component the desired workpiece or blank.
Embossing is a process for creating either a raised or recessed design in sheet metal, by pressing the raw blank against a die that contains the desired shape, or by passing the material blank through a roller die.
Coining is a bending technique wherein the workpiece is stamped while placed between a die and the punch or press. This action causes the punch tip to penetrate the metal and results in accurate, repeatable bends. The deep penetration also relieves internal stresses in the metal workpiece, resulting in no spring back effects.
Bending refers to the general technique of forming metal into desired shapes such as L, U, or V-shaped profiles. The bending process for metal results in a plastic deformation which stresses above the yield point but below the tensile strength. Bending typically occurs around a single axis.
Flanging is a process of introducing a flare or flange onto a metal workpiece through the use of dies, presses, or specialized flanging machinery.
Metal stamping machines may do more than just stamping; they can cast, punch, cut and shape metal sheets. Machines can be programmed or computer numerically controlled (CNC) to offer high precision and repeatability for each stamped piece. Electrical discharge machining (EDM) and computer-aided design (CAD) programs ensure accuracy. Various tooling machines for the dies used in the stampings are available. Progressive, forming, compound, and carbide tooling perform specific stamping needs. Progressive dies can be used to create multiple pieces on a single piece simultaneously.
Progressive die stamping uses a sequence of stamping stations. A metal coil is fed into a reciprocating stamping press with progressive stamping dies. The die moves with the press, and when the press moves down the die closes to stamp the metal and form the part. When the press moves up, the metal moves horizontally along to the next station. These movements must be precisely aligned as the part is still connected to the metal strip. The final station separates the newly-fabricated part from the rest of the metal. Progressive die stamping is ideal for long runs, because the dies last a long time without becoming damaged, and the process is highly repeatable. Each step in the process performs a different cut, bend, or punching operation on the metal, thus gradually achieving the desired end-product shape and design. It is also a faster process with a limited amount of wasted scrap.
Transfer die stamping is similar to progressive die stamping, but the part is separated from the metal trip early on in the process and is transferred from one stamping station to the next by another mechanical transport system, such as a conveyor belt. This process is usually used on larger parts that may need to be transferred to different presses.
Four-slide stamping is also called multi-slide or four-way stamping. This technique is best-suited for crafting complex components that have numerous bends or twists. It uses four sliding tools, instead of one vertical slide, to shape the workpiece through multiple deformations. Two slides, or rams, strike the workpiece horizontally to shape it, and no dies are used. Multi-slide stamping can also have more than four moving slides.
Four-slide stamping is a very versatile type of stamping, as different tools can be attached to each slide. It also has a relatively low cost, and production is fast.
Fine blanking, also known as fine-edge blanking, is valuable for providing high accuracy and smooth edges. Usually done on a hydraulic or mechanical press, or by a combination of the two, fine blanking operations consist of three distinct movements:
Fine blanking presses operate at higher pressures than those used in conventional stamping operations, hence tools and machinery need to be designed with these higher operating pressures in mind.
The edges that are produced from fine blanking avoid fractures as produced with conventional tooling and surface flatness can exceed that available from other stamping methods. Since it is a cold extrusion technique, fine blanking is a single-step process, reducing the overall costs of fabrication.
The three common types of stamping presses include mechanical, hydraulic, and mechanical servo technologies. Usually, presses are linked to an automatic feeder that sends sheet metal through the press either in coil or blank form.
Mechanical presses use a motor connected to a mechanical flywheel to transfer and store energy. Their punches can range in size from 5mm to 500mm, depending on the particular press. Mechanical pressing speed also varies, usually falling between the range of twenty and 1,500 strokes per minute, but they tend to be faster than hydraulic presses. These presses can be found in an array of sizes that stretch from twenty to 6,000 tons. They are well-suited for creating shallower and simpler parts from coils of sheet metal. They’re usually used for progressive and transfer stamping with large production runs.
Hydraulic presses use pressurized hydraulic fluid to apply force to the material. Hydraulic pistons displace fluid with a force level proportional to the diameter of the piston head, allowing for an advanced degree of control over the amount of pressure, and a more consistent pressure than a mechanical press. Additionally, they feature adjustable stroke and speed capabilities, and can typically deliver full power during any point in the stroke. These presses usually vary in size from twenty to 10,000 tons and offer stroke sizes from about 10mm to 800mm.
Hydraulic presses are usually used for smaller production runs to create more complicated and deeper stampings than mechanical presses. They allow for more flexibility because of the adjustable stroke length and controlled pressure.
Mechanical servo presses use high capacity motors instead of flywheels. They are used to create more complicated stampings at a faster speed than hydraulic presses. The stroke, slide position and motion, and the speed are controlled and programmable. They are powered by either a link-assisted drive system or a direct drive system. These presses are the most expensive of the three types discussed.
Dies that are used in metal stamping operations can be characterized as either single-station or multiple-station dies.
Single-station dies include both compound dies and combination dies. Compound dies perform more than one cutting operation in a single press, such as the case of the multiple cuts needed to create a simple washer from steel.
Combination dies are ones which incorporate both cutting and non-cutting operations into a single press stroke. An example might be a die that produces a cut as well as a flange for a given metal blank.
Multi-station dies include both progressive dies and transfer dies, where notching, punching, and cutting operations occur in sequence from the same die-set.
Steel rule dies, also referred to as knife dies, are were initially used with softer materials such leather, paper, or cardboard, but have also found application in cutting and shaping of metals including aluminum, copper, and brass. The steel strip material used for the cutting surface is designed to match the desired shape, and a slot is cut into the die shoe to hold the steel rule material. The characteristics of the material to be cut, such as its thickness and hardness, help establish the steel rule thickness to be used in the cutting blade.
The choice of metal stamping materials used depends on the desired attributes of the finished piece. Stamping is not limited as a fabrication process to just metals – there are numerous materials that can be processed through stamping techniques, such as paper, leather, or rubber, but metals are by far the most commonly used.
In general, metals tend to maintain their malleability and ductility after stamping. Those used in precision stamping usually range from soft to medium hardness and carry a low coefficient of flow. Some of the customary metals and metal types fabricated through stamping include:
Ferrous metals are commonly used in stamping operations, as their low carbon content means they are among the least expensive options available resulting in low unit production costs.
Several important factors and design considerations need to be addressed when performing metal stamping operations.
Post-stamping production operations can include having the stamped product going through deburring, tapping, reaming, and counterboring processes. These allow for the addition of other parts to be added to a stamped piece or for the correction of imperfections in finish or removal of sharp edges that may impact safety.
Deburring involves the removal of shards of cut material that remain on the workpiece after the stamping operation has been completed. Sharp edges may require grinding to remove burrs or may need to be flanged over to produce a smoothed edge and to direct the burred edge to the inside fold where it will not cause injuries or be noticed cosmetically.
Overly narrow projections should generally be avoided in stamped products, as these may be more easily distorted and impact the perception of quality in the finished product.
Where possible, designs should be based on the use of existing dies for standard shapes and bends. The need to create a custom die for stamping will increase initial tooling costs.
Avoidance of sharp internal and external corners in stamped product designs can help reduce the potential for the development of larger burrs in these areas and sharp edges that require secondary treatment to remove. Also, a great potential for stress concentrations exists in sharp corners, which may cause cracking or subsequent failure of the part through extended use.
Overall dimensions for the finished product are going to be limited by the available dimensions of the sheet metal sheets or blanks, and these limits need to be factored for the material consumed in folds on edges or flanges and any additional material removal or use. Very large products may need to be created in multiple steps and mechanically joined together as a second step in the production process.
For punching operations, consider both the direction of punching as well as the size of the punched feature. Generally, it is best to do punching in one direction, so that any sharp edges produced by the punch will all be on the same side of the workpiece. These edges can then be hidden for appearance purposes and kept away from general access by workers or product end-users where they might represent a hazard. Punched features should reflect the thickness of the raw material. A general rule is that punched features should be at least twice the material thickness in size.
For bends, the minimum bend radius in sheet metal is roughly the same as the material thickness. Smaller bends are more difficult to achieve and may result in points of stress concentration in the finished part that may subsequently cause issues with product quality.
When drilling or punching holes, performing these operations in the same step will help to assure their positioning, tolerance, and repeatability. As general guidelines, hole diameters should be no smaller than the material thickness, and the minimum spacing of holes should be at least twice the material thickness apart from each other.
Bending operations should be performed with awareness of the risk or distorting the material, as the material on the interior and exterior surfaces of the bend point are compressed and stretched respectively. The minimum bend radius should be approximately equal to the thickness of the workpiece, again to avoid stress concentration build up. Flange lengths should be more like three times the workpiece thickness as a good practice.
Some of the benefits of stamping include lower die costs, lower secondary costs, and a high level of automation compared to other processes. Metal stamping dies tend to be relatively less expensive to produce and maintain than those used in other common processes. The secondary costs, such as cleaning and plating, are also cheaper than similar treatments for other metal fabrication processes. Stamping machines are relatively easy to automate and can employ high-end computer-control programs that provide greater precision, faster production, and quicker turnaround times. The high level of automation also lowers the cost of labor.
One of the disadvantages of stamping is the higher cost of presses. The dies must also be acquired or created, and producing custom metal stamping dies is a longer pre-production process. Dies can also be difficult to change if the design must be altered during production.
Stamping is used in a variety of applications, especially those involving three-dimensional designs, lettering, or other surface engraving features. Such stamping products are commonly produced for home appliance manufacturers, automotive companies, telecommunications services, aerospace industries, medical equipment manufacturers, and electronics companies. Odds are you have a product in your home that has parts created through metal stamping because it is a process used in everything from your household appliances to your cars.
The specific products and components can range from simple stamping items, such as metal clips, springs, weights, washers, and brackets, to more complex designs, such as those found in engine bases or friction plates. This process is used for producing both parts for large machinery and also incredibly detailed small parts. Micro-precision stamping can create parts with diameters of up to 0.002 inches.
Electronic stampings are electronic components manufactured through the metal stamping process. They are used in a variety of industries, from home electronics and appliances to telecommunications and aerospace. Electronic stampings are available in a number of metals, including copper, copper alloys, aluminum, and steel, as well as more expensive metals, such as platinum and gold. Electronic components produced by the metal stamping method include terminals, contacts, lead frames, springs, and pins. They can be created from ferrous or nonferrous materials. Metal stampings find wide use in computers, electronic equipment, and medical devices. Because of the specialized shapes that can be made by the various stamping processes, many electronics are made by this cold forming process.
For more information, please visit Metal Stamping Services.