This article covers all the information you need to know about Metal Stamping.
Read further to learn more about topics such as:
Metal stamping is a coldworking technique that reshapes sheets or coils of metal into predetermined forms. This process utilizes specialized tooling where a punch applies force to alter the metal sheet. With adequate force, metal stamping can cut or mold a sheet into a specific, pre-engineered shape.
The stamping process begins with the design of the tooling using computer-aided design (CAD) and computer-aided manufacturing (CAM). The tooling is meticulously engineered to ensure each punch, bend, or cut achieves the desired results with the necessary precision. CAD models can be highly detailed, involving complex tooling with numerous parts and components. After the tooling is completed, various methods can be employed to produce the final part.
Metal stamping methods generally fall into three categories: progressive, fourslide, and deep draw. Progressive die stamping uses multiple stations, each performing a distinct step in the stamping process. Fourslide stamping employs four tools simultaneously to reshape and form the workpiece. Deep draw stamping involves pulling the workpiece into a punch to shape it. Each method offers distinct advantages for producing components suited to specific industries and applications.
A metal stamper is a versatile machine capable of performing a wide array of cutting and forming operations. It can consolidate multiple cutting and forming steps into a single tooling process, often completing these tasks in one stroke. Additionally, metal stampers can process multiple parts simultaneously within the same stroke. Their ease of automation and control significantly benefits metal fabricators by boosting production rates, lowering labor costs, and enhancing the quality, repeatability, and precision of the parts. With accurate tooling, metal stampers can efficiently produce parts with intricate designs.
Metal stampers are used to create a diverse range of products, from simple items like washers, springs, hinges, and brackets to complex components used in structural elements, engines, industrial machinery, and automotive parts. Stamped metal products are valuable across various industries and serve numerous end customers.
Various types of metal stamping machines are available, each tailored for specific applications. Some of the most common types include:
Mechanical presses are commonly employed for metal stamping. They utilize a mechanical system, often comprising a crankshaft and flywheel, to generate the necessary force for stamping operations. These presses are renowned for their precision and reliability.
Hydraulic presses utilize hydraulic cylinders to generate the force needed for metal stamping. They are capable of applying high levels of pressure, making them particularly suitable for deep drawing and complex forming operations.
Servo presses are an advanced type of mechanical press that employ servo motors to provide precise control over the speed and force of the stamping process. This modern technology offers greater flexibility and customization, enhancing the accuracy and efficiency of stamping operations.
Progressive die stamping machines are ideal for high-volume production of metal parts. They feature multiple stations, each performing a distinct operation as the metal strip advances through the machine, making them highly efficient for continuous production.
Transfer presses are used for complex stamping operations that involve multiple steps. They utilize a transfer system to move the metal from one station to another within the machine, enabling intricate and multi-stage processes.
Fine blanking presses are specialized for producing precision parts with extremely tight tolerances. These presses are commonly used in industries where part accuracy is critical, such as the automotive and aerospace sectors.
Stamping punch presses are versatile machines used for a variety of metalworking operations, including blanking, piercing, and coining. They are available in both mechanical and hydraulic versions to suit different needs.
Turret punch presses are designed for sheet metal fabrication, allowing for operations such as punching holes, cutting shapes, and bending metal sheets. They are equipped with a turret that holds multiple tools for various tasks.
Hot stamping machines apply heat and pressure to transfer foil or pigment onto the metal surface using a heated die. This method is commonly used for decorative effects and labeling purposes.
Coining presses are specialized for producing coins and other high-precision, flat components with intricate designs. They are engineered to achieve highly detailed and accurate results.
Metal stamping operations encompass the complete series of activities required to shape, cut, or form metal workpieces using stamping machines. This process typically includes several steps: designing and tooling, feeding the material, stamping, quality control, and, in some cases, post-processing. The specific types of metal stamping operations used in a fabrication plant include:
Progressive die stamping involves feeding a sheet of metal into a press, where it passes through various tooling stations, each performing specific metalworking processes such as cutting, bending, and punching. The sheet remains connected to its base strip throughout the process and moves through a conveyor system in the stamper.
At each station, the workpiece is shaped by a die before progressing to the next station. Once all the operations are complete, the press lifts, and the sheet moves horizontally, gradually forming the part. At the final station, the finished part is ejected from the sheet.
Advantages of progressive die stamping include the rapid production of parts with complex geometries and tight tolerances, high repeatability, and reduced labor costs. The process combines multiple metalworking steps into a single tooling. However, due to its limitations in making deep punches, progressive die stamping is not suitable for parts requiring deeper punches.
In transfer die stamping, the workpiece is initially detached from the metal sheet and then moved from one stamping station to another. This allows the separated materials to be transferred to different presses, enabling the manufacturer to produce a variety of parts simultaneously.
Transfer die stamping is ideal for forming large parts. Since the part is detached from the base metal sheet, the punch can penetrate deeply without disrupting other operations, making it well-suited for deep drawing applications. Additionally, it is beneficial in processes with multiple intermediate steps, where early separation of the part enhances overall efficiency.
In fourslide or multi-slide stamping, the rams are positioned horizontally and move towards the workpiece. This process differs from traditional stamping, which uses a downward stroke of a press. Each slide in a multi-slide stamping machine is equipped with a tool that can simultaneously perform bending, twisting, cutting, or forming actions in a horizontal direction. Multi-slide stamping machines can feature more than four moving slides.
Fourslide stamping is particularly well-suited for creating complex and multiple bends, bends greater than 90 degrees, and forming cylindrical parts. It excels in producing twists and offers several advantages, including rapid production, cost-effective tooling, and lower initial expenses. Additionally, it generates less scrap and reduces material costs by allowing the raw metal to be purchased closer to the finished part's width.
In compound stamping, a single downward stroke of the die can perform multiple operations, including cutting, bending, and punching. The metal sheet is continuously fed into the stamping machine, and the finished part is ejected from the strip of metal. This process allows a single stroke to create multiple cuts and holes, eliminating the need for multiple dies and strokes, which reduces production time and enhances cost efficiency.
Compound stamping offers high repeatability and precision. However, it is generally limited to forming flat metal pieces with simpler geometries, such as washers.
Hot stamping, also known as press hardening or hot press forming in Europe and Asia, is a thermoforming process that incorporates heat treatment during stamping. Developed in the 1970s initially for hardening steel used in agricultural tools, it has since evolved to produce high-strength, lightweight components for the automotive industry.
In hot stamping, the blank is first heated in an oven or furnace to the required temperature, typically around 1700°F. It is then transferred to a hot stamping press, which rapidly closes over the blank, holding it in place for several seconds until it cools. The hardened and formed part is then ejected for final finishing.
Hot metal stamping comes in two forms: direct and indirect. In direct hot stamping, the blank is placed directly into the oven or furnace for heating. In indirect hot stamping, the blank is cold formed before undergoing the heating process.
Hot stamping is favored over cold working for several reasons, including improved material properties and formability. The process enhances the strength of the workpiece while reducing its weight, making it particularly suitable for automotive parts. Additionally, the quenching and forming stages ensure that the workpiece achieves the desired microstructure.
However, hot metal stamping is slower compared to cold stamping. While a cold stamping machine can produce 20 to 1500 strokes per minute, a hot metal stamping press typically takes 10 to 30 seconds per stroke, with longer times required for thicker metals. Delays may also arise during post-stamping finishing processes.
In the United States and Canada, a wide variety of metal stamping machines are available, playing a crucial role in modern manufacturing. These machines facilitate the efficient and cost-effective mass production of metal components across diverse industries, including automotive, aerospace, electronics, and appliances. By supporting technological advancements and contributing to economic growth, these machines are integral to many sectors. Below, we explore some of these machines and the features that have made them popular.
The E2W series presses from Komatsu are renowned for their precision, reliability, and energy efficiency. Featuring advanced servo-driven technology, these presses offer precise control over the ram's motion, ensuring consistent and accurate stamping results. Designed to minimize energy consumption and reduce operating costs, the E2W series is a popular choice for a wide range of metal stamping applications.
AIDA's NC1 series presses are celebrated for their robust construction, high-speed performance, and versatility. Equipped with advanced controls and automation features, these presses enable fast and efficient production. Known for their precision and capability to handle a wide range of stamping applications, the NC1 series is a popular choice among metal stamping companies.
The Bliss C1 Straight Side Press is renowned for its durability and rigidity, ensuring stable and accurate stamping operations. Its straight side design offers easy access to the working area, facilitating straightforward die changes and maintenance. This press is well-suited for handling heavy-duty stamping applications with efficiency and reliability.
The DSF Series Servo Presses from SEYI are known for their precision and high-speed performance. Utilizing servo motor technology, these presses accurately control the ram's movement, leading to reduced energy consumption and increased productivity. They are particularly well-suited for applications involving complex forming and intricate shapes.
The Heim Maxi Stamper Press is recognized for its heavy-duty construction and dependable performance. Designed to handle large and demanding stamping jobs with consistent accuracy, these presses feature advanced safety mechanisms and user-friendly controls, making them a preferred choice for various metal stamping operations.
Since specific models and their features may evolve, it is advisable to consult manufacturers or industry experts for the most up-to-date and comprehensive information on metal stamping machines available in the United States and Canada.
Metal stamping involves a range of metalworking processes, such as blanking, bending, and drawing. Metal stamping machines are versatile tools designed to convert sheet metal into functional components. These machines typically handle tasks categorized under cutting and forming processes.
Cutting involves applying a shearing force strong enough to divide material into sections. For the material to separate at the cut location, the shearing force must exceed its ultimate yield strength.
Blanking is a metal fabrication process where a workpiece is cut from a base metal sheet. During this process, the punch's downward stroke shears the outline of the workpiece, which is then called a blank. Blanking is typically the first step in metal fabrication, making the workpiece easier to handle for subsequent operations. The excess material is discarded and can often be recycled.
Fine blanking is a specialized form of blanking where the base metal sheet is supported by high-pressure pads. One of these pads features an impingement ring (V-ring) that punctures the perimeter of the piece before it contacts the die, preventing metal flow and directing it towards the punch. A counter-die applies reciprocating pressure at the bottom of the workpiece to maintain flatness. This tight clamping and balanced pressure prevent plastic deformation, resulting in smoother, fully sheared edges. After punching, the tool opens, and an ejector pin pushes the finished part out.
In fine blanking, the clearance is minimized to less than 0.0005 inches, which, combined with high pressures, achieves a fully sheared edge. This clearance is significantly smaller compared to traditional punching, leading to accelerated tool wear due to occasional die-punch contact. Deburring is necessary as the impingement ring leaves a small area attached to the finished part after punching.
Fine blanking is ideal for parts that require precise flatness, geometric accuracy, and smooth edges. It can also produce small holes in parts. However, it is generally more expensive than traditional blanking methods.
Punching, also known as piercing, is similar to blanking but focuses on creating small shapes, such as holes, in the workpiece using a shearing force. During this process, a portion of the material is cut from the blank and discarded after ejection. Punching can be integrated with the blanking step, allowing both operations to be performed in a single downward stroke of the punch.
Trimming is the process of cutting away the outer perimeter of the workpiece to achieve the desired profile. The excess material is typically discarded but can also be recycled.
Lancing is the process of partially cutting a portion of the workpiece without fully separating it from the base sheet.
Forming is the process of reshaping a material by applying compressive and tensile stresses to induce deformation. Using dies and punches, this method creates bends, curves, or complex shapes in the metal.
Bending is a metalworking process used to create angles or curves in a workpiece by inducing plastic deformation. This is achieved by pressing the workpiece, which is held in place by a stationary bottom die, with a forming die. The downward stroke of the punch shapes the workpiece into the desired bend profile. Several bending methods can be employed in a stamping process, including the following:
In bottom pressing, or bottoming, the punch presses the workpiece against the bottom surface of a V or U-shaped die, which defines the final bend angle. This method produces precise bends and reduces the tendency for springback in the workpiece due to the application of greater bending force.
In air bending, or partial bending, the punch presses the workpiece so that it does not contact the bottom surface of the die. A sharper bend can be achieved by applying more bending force. However, this method is generally less accurate compared to bottom pressing and coining.
Coining is a bending process where the workpiece is compressed between the punch and the die, with the compressive force being up to 30 times greater than in other bending methods. The punch and die work together to impart precise angles or curvatures to the workpiece. This method provides high accuracy in bending and effectively eliminates the tendency for springback.
In flanging, or wipe bending, the workpiece is positioned between the bottom die and an upper pressure pad, while a forming punch pushes down the protruding material. Springback is accounted for by adjusting the angles of the die and punch. This method is particularly effective for creating perpendicular bends.
Drawing is a metalworking process used to shape a blank into a hollow or concave form with seamless edges and varying diameters. This process involves clamping the blank into a die with a blank holder and forcing it through the die using a drawing punch. As the punch moves downward toward the cavity, the workpiece undergoes a complex sequence of stresses and deformations to achieve the final shape.
If the blank is drawn to a length greater than its diameter, the process is known as deep drawing. When the drawing does not exceed the diameter of the blank, it is referred to as shallow drawing.
Coining is a metalworking process that modifies the surface roughness of a workpiece through compressive stress, leading to plastic deformation. This operation reduces the surface grain size and hardens the surface while preserving the workpiece's toughness and ductility.
Note that this process differs from coining in bending. Coining is commonly used in the manufacturing of coins, buttons, and badges.
Embossing is a process that raises a design or pattern above the surface of the metal, while debossing creates a depressed design by pressing it into the metal. Both processes are achieved by pressing the workpiece between a male die and a female die. These techniques are used to label or decorate a workpiece with distinctive details such as text, logos, and images.
Dies are the sets of tooling used to cut or shape the material to create specific customized parts. Dies may be classified as a cutting die or forming die, but they have almost the same components:
Die assemblies can be categorized into the following types:
Simple dies are designed to perform a single task per stroke. They are typically used in fabrication processes with few steps and for low-volume production. While they may be less efficient, simple dies excel in precision for operations such as cutting or bending.
Compound dies are capable of performing multiple cutting operations in a single stroke, such as simultaneous blanking and piercing. They are ideal for producing parts with multiple cuts and complex designs more quickly. However, compound dies are less suitable for forming operations, which require greater force. A common application of compound dies is in the production of flat washers.
Combination dies are advanced dies capable of performing multiple cutting and forming operations in a single stroke. By simultaneously executing tasks such as trimming and flanging, combination dies enhance production efficiency and reduce processing time.
Progressive dies are designed to cut or form a workpiece progressively through a series of stations arranged within the die, following the sequence of fabrication steps. The metal sheet is continuously fed into the stamper, moving horizontally along the conveying system while the die is open. It stops at each station in turn, with each station spaced equally apart. The final step typically involves ejecting the stamped part from the base sheet.
Transfer dies consist of a series of multiple dies arranged on the production floor according to the sequence of fabrication steps. The process begins with the workpiece being separated from its base metal sheet at the first station, after which it is transferred through the series of dies using a conveying system. Multiple sets of transfer dies can be employed to run different products in parallel.
Transfer dies are particularly suited for fabricating large and complex parts that require specialized dies for precise operation.
The metals commonly used in stamping processes include:
Copper alloys are frequently used in stamping processes due to their outstanding electrical conductivity, corrosion resistance, and malleability. Common copper alloys employed in stamping include:
Brass, an alloy of copper and zinc, is renowned for its attractive gold-like appearance. It is commonly used in decorative and architectural applications, as well as in electronics, plumbing fittings, and musical instruments.
Bronze, an alloy of copper with elements such as tin, aluminum, or silicon, is valued for its durability. This makes it ideal for applications like bearings, bushings, and sculptures.
Steel is a broad category of alloys primarily composed of iron and carbon. The mechanical properties of steel depend largely on the concentration of alloying elements. Higher carbon content increases hardness but also makes the steel more brittle and less ductile, while higher levels of nickel and chromium enhance corrosion resistance. Steel alloys are generally known for their high strength and toughness, as well as their ability to withstand extreme temperatures, although they can be challenging to stamp.
The most common steel alloys used in metal stamping are stainless steel and carbon steel.
Common steel alloys used in stamping processes are:
This basic alloy of iron and carbon is widely used in automotive parts, machinery, and construction materials due to its strength and cost-effectiveness.
Stainless steel, which contains chromium, offers excellent corrosion resistance. It is ideal for applications that require both strength and resistance to rust and staining, including kitchen appliances, medical equipment, and outdoor architectural elements.
Aluminum is an affordable, lightweight, non-ferrous metal with excellent corrosion resistance and the ability to withstand extreme temperatures. It also offers good thermal and electrical conductivity and is highly valued for its decorative qualities. Due to its ductility, flexibility, malleability, and high strength-to-weight ratio, aluminum can be stamped easily and effectively.
Commonly used aluminum alloys are below:
This commercially pure aluminum alloy is known for its excellent formability. It is commonly used in applications such as food packaging, chemical equipment, and heat exchangers.
This alloy combines good strength with exceptional workability, making it suitable for use in cooking utensils, heat exchangers, and automotive components.
Renowned for its high strength and heat-treatable properties, this alloy is commonly employed in aerospace, automotive, and structural components.
Offering excellent corrosion resistance, this alloy is frequently used in marine applications, signage, and fuel tanks.
Here are some key advantages of metal stamping:
Stamping processes are cost-effective due to their speed and efficiency, which reduce labor costs and minimize material waste. The durability of stamping dies allows them to produce thousands or even millions of parts before needing replacement, further lowering overall costs.
Metal stamping provides high precision and accuracy in part production. Advanced technologies such as computer-aided design (CAD) and computer numerical control (CNC) ensure exact dimensions and tight tolerances.
Automation in stamping processes, including progressive and transfer stamping, enables rapid production and shorter lead times. This efficiency is crucial for meeting tight production schedules and quickly responding to market demands.
Metal stamping is adaptable to a variety of metals, such as steel, aluminum, brass, and copper. This versatility allows manufacturers to produce a wide range of components for diverse applications and industries, from intricate electronic parts to large structural components in construction.
Stamping processes reduce material waste through precise cutting and forming. This not only lowers raw material costs but also supports environmental sustainability by minimizing scrap and energy consumption.
Stamping can create complex and intricate part geometries with high precision, often in a single operation. This capability simplifies production by reducing the need for multiple manufacturing steps and secondary operations.
Stamped metal components are known for their robustness and durability. The cold-working process enhances the metal's strength and resistance to wear, corrosion, and other environmental factors, making it ideal for applications requiring long-lasting and resilient parts.
Die stamping is a cold forming process that takes a sheet of metal, referred to as a blank or tool steel, and cuts and shapes it using a single or series of dies to create a desired shape or profile. The force that is applied to the blank modifies and changes its geometry...
An eyelet is a metal, rubber, or plastic ring with flanges are used to strengthen or reinforce holes punched in thin fabrics. It is a smaller counterpart of a grommet that is bigger in size and used for more heavy duty materials...
A fastener is a non-permanent or permanent mechanical tool that rigidly connects or affixes two surfaces or objects together. Non-permanent fasteners can easily be removed without damaging the joined materials...
A metal bracket is a fastener or connector designed to secure and hold two pieces or objects together. They are used to support shelves, stabilize equipment, fasten uprights, or serve as decorative accents. Metal brackets come with...
Shim Definition: The material used to cover empty spaces is referred to as a shim. For instance, window and door jamb construction frequently involve the usage of construction shims. A shim can be made from materials on hand, especially when...
A metal washer is a small flat piece of metal that has a hole in the center and is used as a spacer, a method for absorbing shock, or distributing the load of a fastener. The hole in the middle of a metal washer allows for a bolt or screw to pass through...
The metal stamping process began during the industrial revolution as a cold forming means for producing frames and handlebars for bicycles. From its beginnings in Germany, it has grown into an essential part of modern industry for the production of parts and components for a wide variety of industries...
A self-drilling screw is a type of tool that has the same design features as a drill bit or cutting tool. As the name implies, self-drilling screws do not require a pilot hole in order to perform as a fastener...
Bolts are mechanical devices used in assembling and fastening objects, typically used with a matching nut. They are designed to be installed in aligned unthreaded holes of multiple parts...
Contract manufacturing is a business model in which a company hires a contract manufacturer to produce its products or components of its products. It is a strategic action widely adopted by companies to save extensive resources and...
Precision sheet metal fabrication is a common manufacturing process where the structure of a metal workpiece is cut, bent, and assembled by machining. There are any number of operations that are performed in the creation of a finished sheet metal product...
Sheet metal fabrication is metal that has been formed into thin and flat sheets which is then cut and bent into various shapes. Different metals, brass, steel, copper, tin, titanium, aluminium, etc., can be made into sheet metal...
Stainless steel can be fabricated using any of the traditional forming and shaping methods. Austenitic stainless steel can be rolled, spun, deep drawn, cold forged, hot forged, or stippled using force and stress...
Secondary manufacturing processes, or fabrication, work on products from primary processes to create a metal part or structure that is suitable for end-use. In these processes, semi-finished metal products are reshaped and joined...