Metal Stampings

View A Video on Metal Stampings - A Quick Introduction

Metal stamping processes produce large volumes of products and parts with uniform precision at high speeds and low cost. Metal stamping presses and fourslide presses are capable of producing two-dimensional and three-dimensional parts, with simultaneous or continuous stamping, pressing, cutting and forming. Copper and brass stampings are commonly fabricated into household fixtures, plumbing accessories or jewelry. Sheet metal stampings and steel stampings are fabricated into a number of larger, three-dimensional parts such as automotive stampings and deep drawn metal stampings, which are deeply three dimensional parts such as pots and pans. Progressive stampings and fourslide stampings are continuous processes which fabricate small, precision parts, such as electronic stampings,  medical stampings, metal clips, spring clips and metal brackets; because these are made as part of one continuous process, these are typically shortrun stampings, produced at a high volume over a short time span.

During press operation, the slide, or ram, maintains movement to and from a motionless table called a press bed. The die, a press tool consisting of a specially designed cavity, shapes metal parts from the inserted sheet metal. The upper component of the die connects to the press slide, and the lower component connects to the press bed. A die component called the punch performs the necessary shaping operation by pushing the sheet metal through the die. Some metal stamping process utilize multiple dies and/or punches. After the metal stampings are formed, they are typically subjected to one or more secondary processes. Plating increases the corrosion resistance, solderability and wearability of the part. The most common plating materials include gold, palladium, nickel and tin; metal can be pre-plated to avoid this secondary process. Cleaning removes oils and films from the metal stampings. Heat treating processes increase the strength of the product. The part is stamped in the soft state before it is hardened by heat treating in order to circumvent its tendency to crack when formed or coined. Sharp corners are removed by the deburring process, which can be done by either abrasives or chemicals.

Stamping presses activate metal forming with force, speed and precision. Metal stampers use mechanical and hydraulic presses, both of which are available in a wide variety of sizes, tonnage capacities, stroke lengths and operating speeds. Mechanical presses produce energy in the flywheel, which is then transferred to the crankshaft, electric shaft or eccentric gear. Gap frames are a type of mechanical press often utilized in applications where the stock is fed by hand; straight frames are ideal for progressive die and transfer die applications. In hydraulic presses, a controlled force is actuated by hydraulic pressure, which is used to move one or more rams in a preset sequence. Hydraulic presses-which have a variety of types of frames, including C-frames, straight sides, H-frames and four-column, have the ability to deliver full power at any point in the stroke. These presses are ideal for deep drawing, short runs, precision metal stampings, lower-speed high-tonnage blanking with long feed lengths and work requiring repeatable pressure rather than repeatable depth of stroke. Progressive presses have multiple stations which stamp different attributes into parts as a metal coil moves through the press; parts are cut and separated on the final step. Similarly, transfer presses have multiple stations for the completion of a part, but parts are separate sheet metal pieces rather than parts along a continuous coil. Fourslide presses have four moving slides which allow the automated press to manipulate parts along both axis, completing multiple aspects of stamping, cutting and shaping on parts at one processing stage.

Metal stamping services are cost-effective because the process is able to produce material-intensive parts at production rates that are much greater than what is possible using other traditional methods. Metal stamped parts are precise, highly repeatable and capable of precision tolerances. Many parts made through other metal forming processes, such as casting, die casting, forging, machining or fabricating, could just as easily be designed for stamping. Metal stamping dies cost less than other tooling, like molds, forging and casting dies and expendable cutting tools, among others. The quality, accuracy, function, wear life and appearance of parts can be greatly improved by designing them to be stamped. Metal stamping allows parts to be made of tougher and harder material than other processes allow, including such materials as stainless steel, nickel, cold rolled steel, aluminum, brass, bronze and galvanized steel. Often the secondary processes can be reduced in number or eliminated altogether to reduce cost even further.

Image Provided By Micro Forms, Inc.	Image Provided by Talan Products, Inc.

---

Metal Stamping Types

• Automotive stamping is a metal forming process in which flat stock sheet metal or metal coils are precisely shaped into three dimensional automotive parts in a stamping press. 
• Brass stampings are formed during metal forming processes in which flat stock brass sheets or brass coils are precisely shaped in a stamping press.
• Deep drawn stampings convert flat sheet metal into three-dimensional shapes-including cylindrical, shell-like, cup-like, rectangular and square shapes-whose lengths (depths) exceed the radius of the part. As the flat metal moves over the die, the metal blank is restrained on either side of the die opening by a blankholder; the metal stampings punch then pushes the secured blank into the die stampings cavity, creating the desired shape.
  
• Electronic stampings are metal stampings of electronic components.
  
• Fourslide stampings is a specialized metal stampings process that allows fourslide stampings to produce complex stamped parts from strips and wires with multiple bends and twists, as well as metal parts requiring bends greater than 90°. Fourslide stampings work with forming, sliding tools, regulated by cams, that glide into the metal stampings blank from four directions at right angles to one another, bending the metal around a vertical mandrel.
  
• Medical stampings are metal stampings and metal stamped parts manufactured specifically for use in the medical industry.
• Metal brackets are simple supportive structures that are used for both fixed and flexible joints and project from a wall or a similar surface to hold or bear the weight of the projecting surface.
• Precision metal stampings are formed during metal forming processes in which flat stock metals are precisely shaped in a stamping press.
• Progressive die stampings utilizes several die stampings workstations, unlike the usual single metal stampers workstations, through which the sheet metal sequentially moves to complete multiple operations of the die stampings process.
• Sheet metal stamping is a metal forming process in which flat stock sheet metal or metal coils are precisely shaped into metal parts in a stamping press.
• Short run stampings produces between five and ten thousand pieces, and the cost of the dies themselves is greater than the cost of the parts produced. Labor costs are higher per piece, materials are more costly, setup time is greater and other cost factors are higher in short run stamping than conventional metal stampings, because of the greater number of metal stampers and operations involved.
• Spring clips are one-piece fasteners that slip into holes or onto edges.

---

Metal Stamping Terms

Alloy - A compound consisting of more than one metal or the combination of a metal and a nonmetal. The resulting compound consists of properties different from those of the metal stampings components.

Annealing - The metal stampings procedure whereby a metal is softened through heating and cooling treatments.

Base Metals - Common metal stampings consisting of inexpensive metals, such as aluminum, zinc, lead, nickel and tin, that are easily oxidized.

Blankholder - A metal stampings mechanism that ensures that the blank does not move during the drawing process.

Blanking - The process of punching, cutting or shearing predetermined shapes out of metal stampings stock.

Bottoming Stamp - A metal stamp or weld mark that signifies that the form die stampings are on the bottom.

Brazing - Metal stampings that join two metals by filling the space between the metals with a nonferrous metal, the melting point of which remains lower than the two metals joined together.

Burrs - Jagged edges or protuberances on the surface of metal stampings created by metal stampers during metal stamping, die stampings or other industrial applications.

Cam - A mechanism that moves or works at an angle to the metal stampings press stroke.

Column Press - A four-post, single slide press.

Compound Die - A stamping die that performs multiple stamping operations, such as blanking, piercing and forming, in one press stroke.

Crank Press - A mechanical press whose slides are activated by a crankshaft.

Cup - A cylindrical sheet metal part or shell that is closed on one end. Cups are the product of the first step in deep drawing.

Deburr - The removal of jagged edges and protuberances on metal surfaces, known as burrs, through abrasive or chemical means.

Dope - A compound used to lubricate the stock during the forming portion of the drawing process.

Draw Bead - A rib-shaped projection on the draw ring or hold-down surfaces that is useful in controlling the rate of metal flow during deep draw processes, especially in the manufacturing of irregularly shaped stampings.

Ductility - The ability of an object to accept bending or reforming without fracture.

Ferrous Metal - A metal such as steel that contains a significant portion of iron.

Hard Tooling - Also called "dedicated tooling," it is a procedure involving the multiple production of one specific part.

Heat Treating - A secondary operation in the metal stamping process in which the strength and hardness of a metal part is increased through controlled cycles of heating and cooling.

Insert Molding - The injection of molten plastic into the surrounding area of metal stamping parts in order to combine the stamping parts into a single piece.

Lead Time - The amount of time from product order to product availability that it takes to complete product manufacture.

Mechanical Press - A press that uses mechanical means to complete stamping operations. In mechanical presses, a shaft conveys motion to the punch.

Non-Ferrous Metal - A metal, such as aluminum or zinc, in which iron is not a main component.

Notching - The removal of the edges and corners of a metal blank.

Plating - Also called "electroplating," it is a secondary operation in the stamping process that involves coating a metal part with another metal substance by electrical means to increase the corrosion resistance of the part.

Precious Metals - Also called "noble metals," they are expensive metals, such as gold, silver and platinum, which remain resistant to oxidation and corrosion.

Punch Press - A standard stamping press that reshapes material through the application of compression.

Secondary Operations - Treatments, including cleaning, heat treating, plating and deburring, performed after the initial metal stamping process to refine the stamped part.

Soft Tooling - Tooling procedure involving the production of multiple part configurations.

Stroke - The completion of one full movement of the stamping press.

---