A company’s accomplishment to expand and innovate competitively lies beyond the proper planning and knowledge of the business. We need to make sure that everything fits into achieving the goal of giving high-quality services and products- just like in the metal stamping process.
We may wonder how they manage to create a piece of stamped metal to work in a product?” Of course, there are different ways to do stamped parts, but properly knowing the process by heart is fundamental. It should be based on the product and materials involved and the quantity of production, among others.
Gold precision will present you with nine (9) commonly used steps in fabricating stamped metals.
During the blanking process, a large coil or metal is cut into smaller, easily manageable pieces. It uses a die to cut metal into a specific shape; the pierced-out part into the primary metal is then called “blank.” Manufacturers mainly use blanking to improve the efficiency of stamped metals for other processes and finishing operations.
The blanking process involves many advantages such as:
- It can minimize the risk of producing stamped parts with rough edges or ridges.
- It takes little time to make parts.
- It has small to no changes in the quality of parts for long production runs.
- It can minimize waste because the primary metal stock is reusable.
- And last but not least, the blanking process is a choice for stamping metal parts that need strict tolerance.
This step is highly applicable for stamping materials like carbon steel, stainless steel, and aluminum. If you opt for mass production of components, blanking is the right one for your product. Most pieces for industries of aerospace, automobile, and home appliances go through blanking.
Piercing and blanking work simultaneously but are two different steps. Unlike blanking, piercing’s primary metal is from the scrap metal where blanking gets its workpiece. It is a shearing process needed for stamped metals with holes, slots, and other cutouts. Usually, it is a cold-forming process using a punch and a die, but it can also be used at hot stamping.
There are several types of piercing which is very useful for other processes, namely:
- Lancing- it only does shearing and modification (e.g., making tabs, vents, and louvers) and not cutting out or diminishing the amount of metal.
- Nibbling- it is used for a series of overlapping cut sheet metals with complex shapes.
- Shaving- this type of piercing is by the finishing operations to smoothen edges and parts and make components more accurate in shape and size.
- And other types are perforating, notching, and cut-off.
For less cost and fast production, the piercing process is an impeccable choice in helping you save up funds and staffing costs.
One of the most commonly utilized steps is the drawing process. This process produces hollow cylindrical or box-shaped stamped metals- just like products including oil sinks and metal sinks. Here, a sheet metal needs to undergo a die and mechanical pulling or stretching to achieve the desired length and shape.
There are two types of drawing- deep drawn and shallow drawing. This metalworking process is suitable for alloys, aluminum, copper, nickel, brass, and steel. Aside from its versatile application, many manufacturers use drawing because it has a long list of pros.
The drawing process may include:
- producing high-strength, low-weight, and seamless stamped parts
- better fast production
- creating detailed and accurate complex shapes
Bending is a general technique of forming; it uses a specially designed die or a general die in bending or folding a metal sheet in a single and straight axis. This process typically assumes after the drawing process. A machine pushes into or against the metal forming three-dimensional components from a sheet or two-dimensional pieces.
This metal stamping step may involve cold bending or hot bending, depending on the tensile strength of the metal. Angles from a bend-processed stamped part make L, U, V, and other shapes. Meanwhile, bending metals using a machine can also be called mechanical bending.
Aside from all the information above, there are some considerations when bending:
- Choose a pliable metal (e.g., alloy, brass, steel, etc.).
- Always follow the grain lines of the metal when bending to avoid cracking.
The bending process offers a great deal in stamping metals as it produces higher precision and consistency in product development. However, in ensuring its quality and accuracy, the bending angle and radius of the metal must be controlled or reduced by the spring back of the bent part.
This step is somehow a division of the bending process and is also called free bending. The only difference is that the metal sheet is partially bent only, indicating low pressure and power. Here, the metal is bent by a punch into a die but not reaching the lower bottom of the cavity. Thus, air bending can have a slight downside in terms of bent accuracy but has a potential for flexibility.
Bottoming and coining
Both bottoming and coining are bending techniques that can give more accurate stamped parts than air bending- pressing the metal against a die. Bottoming or bottoming punch is a forming process that is exclusive for V-shaped components only. It can eliminate spring back by applying additional force to the tip of the point.
On the other hand, coining, from the word itself, is traditionally known to make coins but is also capable of different shapes. It applies deep penetration or extreme pressure to push a metal sheet against a die, making it a good choice for thick and hard sheet metals.
Some advantages you can get from these two processes are:
- You can save money and time by minimizing work from deburring and grinding processes. Through their high degree of force, stamped metals are likely to have smooth edges.
- You can have precise, accurate shapes and repeatable and permanent forms by bottoming and coining with no spring-back effects.
Forming is a metal bending technique applying a condensed and malleable force in releasing the internal stress of metal deformation. Also, it is simply a re-shaping of a metal part producing multiple bends. Although, this step is not primarily applicable for some complex shapes and for bending very sharp angles. That’s why most of the time, forming is likely to be used in U-shaped vessels.
In this process, you must be mindful of controlling force to avoid cracking stamped metals. Industries such as aerospace are fans of the forming process.
Pinch trimming is a particular method of cutting vertical walls or stretched vessels by punching sheet metal between two dies- separating the scrap from the workpiece. Trimming is beneficial for nearly finished or finished stamped parts to remove excess edges.
In addition, this process serves as an edge treatment as well. It improves edge quality through refining and smoothening of surfaces.
Lancing is a cutting process; commonly applied for minor cuts to make metals more flexible. Here, sheet metal is cut in three sides, leaving one side connected or raised to the sheet- creating an opening or hook-like feature. This step may decrease metal heat by making tabs and vents. Others may find lancing as functional in the progressive stamping process.
There are nine excellent and typical steps in metal stamping that are functional in their ways. Whatever action you use and apply, always remember two things- quality and application. It is better to talk with professionals first, precisely create a plan, and choose the right step according to your project.