We can find many items in our day-to-day lives are made from metal stamping machines. From the car you drive and the kitchen utensils you use, metal stamping plays an important role in creating many products. In this article, we will introduce the types of stamping processes, applications, and key advantages. Before we introduce more about metal stamping, we need to understand what is metal stamping.
What is metal stamping?
Metal stamping is a cold-forming process that a machine with dies and stamping presses to create a metal shape out of the sheet metal with extreme force and speed. The sheet of metal used in the process is either in the form of a coil or in the form of a blank. The sheet metal is then placed in the stamping press where the tool and die surface forms it into the desired shape. This process can be applied to a wide range of materials, the most common types of material are steel, brass, and aluminum. The process of stamping can be varied according to the product that is being made. It can be a one-step process that each stroke of the press produces the final shape, or it can be done by a series of steps to form the final shape. Metal stamping already has a history of over one hundred years, the stamping machines have been improved and the introduction of computer numerical control (CNC) has made the stamping process more accurate as it allows the designs to be created and tested on a computer before being fed into the stamping machine. The design must be as precise as possible to make sure that each punch can maintain a proper clearance at optimal part quality.
Metal stamping can be applied to many products across a wide range of industries. Popular industries that employ metal stamping include aerospace, automotive, electronics, telecommunication, etc.
Advantages of Metal Stamping
There are several benefits of using metal stamping. Since metal stamping is a cold-forming process, it does not require the heating of the material to form the desired shape. You don’t need to wait for the workpiece to cool off and there is little need for secondary operations, these have made the overall process less expensive when compared to other hot forming processes. In addition, if you would like to produce the product in mass quantity, metal stamping can provide you a high consistency in mass production and ensure the uniformity in products by controlling the entire stamping process via CAD (Computer-aided design) and professionally operated machines with tools.
Types of Metal Stamping Processes
Metal stamping is a complicated process that involves a wide array of forming techniques such as blanking, piercing, punching, coining, embossing, flanging, and bending.
Blanking
Blanking is commonly being set as the first step of the stamping process that cuts large sheets or coils into smaller and more manageable pieces for further processing. This is the step where to define the hole diameter, geometry, and the spacing between edge-to-hole when inserting the first piercing. The purpose of this step is to minimize and avoid burrs that may drive up the cost or extend lead time.
Piercing
Piercing is one of the basic forms of metal stamping. It uses a machine tool to punch holes through the sheet metal. The punched material is then discarded from the workpiece and won’t be used in the entire process later on. It is very important to maintain instantaneous throughout the punching motion to ensure that there are no deformations surrounding the hole formation.
Drawing
Drawing is the actual metal stamping process when referring to metal stamping. During the drawing process, the machine will hold two end sides of sheet metal and a die with a certain shape is placed below the sheet metal. A punch will then create a high impact force to push the sheet metal onto the die to deform the sheet metal and make it match the die’s shape. There are two types of drawing - shallow drawing and deep drawing. Shallow drawing is when the primary blank is drawn shorten than its diameter. Whereas, a deep drawing is when the primary blank is drawn longer than its diameter.
Embossing
Embossing is used to create a raised or recessed effect on the opposite side of the blank by forcing a blank against a die in the desired pattern. It can also be done by passing the material blank through a roller die. Embossing is mainly used for creating decorative patterns on the workpiece. Aluminum is the most popular material for embossing due to its high machinability and lightweight.
Coining
Coining is traditionally used for making coins. It is a technique that a small piece of metal is stamped to create the shape and features of a coin. Coining is a close die forging technique in which the metal is stamped wholly or partly by closing two dies toward each other on both sides of the metal. Coining can create smoother edges and finer details to the workpiece. This process is normally required when the edges of a stamped part need to be flattened or when you want to add strength to the workpiece. Coining also helps to avoid secondary finishing such as grinding and deburring.
Lancing
Lancing is a unique process that is used for making vents, openings, or tabs. Unlike blanking and piercing, this process does not remove unwanted metal during the process but creates a slit on the sheet metal. Lancing can create specialty designs and shapes for different types of material.
There are many different processes covered under metal stamping. No single process is the best but you should choose the most suitable processes depending on the product requirement. With a full understanding of these stamping processes, you can have a better design on the overall process to reduce scrap and improve the production speed without sacrificing the quality. It also helps to save more cost on your production.
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