Manufacturers use blanking to punch pieces in specific shapes from sheets or strips of raw material. The punched-out piece is called the “blank,” hence the term “blanking.” Blanking is most often performed with tools made from hardened steel or carbide, which work on metals like aluminum, carbon steel, stainless steel, and even plastic.
Blanking has many benefits, but manufacturers must take some considerations into account before embarking on a full course of metal blanking. Although this process is a quick and cost-effective way to produce a large number of identical pieces, these punched-out pieces may have burrs or cracks on the edges. However, these drawbacks can be avoided by using high-quality tools, and they can be corrected by post-processing the blanks.
Although blanking sounds simple, this basic option can accommodate many variations. A full overview continues below.
Benefits of Blanking
Machinery used for blanking ranges from simple punches and dies to sophisticated CNC machinery. Blanking equipment can quickly be configured to end product specifications, and the process itself takes little time per part as it involves simply feeding the primary metal stock continuously into the blanking machine.
Because of this, blanking can perform long production runs that require little or no changes to the machinery or base material. The straightforward process also allows you to construct materials to strict tolerances with little part-to-part variation, and technology has become so sophisticated that it can build multiple geometries using a single process.
Furthermore, because the primary metal stock can be reused, blanking can help manufacturing firms reduce their material waste. Due to these benefits, blanking is commonly used to mass produce components for industries such as aerospace and automobile manufacturing. It’s also used for high-volume fabrication of parts for common household appliances.
Differences Between Punching and Blanking
Punching and blanking are often confused with each other since both processes remove pieces from a base sheet of material. Adding to the confusion is the fact that the same terms, punch and die, are used in both operations.
A simple way to remember the difference between the two processes is to note that an alternate term for punching is piercing. Manufacturers sometimes refer to this process as piercing because the desired end product is the pierced sheet of metal, not the metal that’s been punched out of it.
As discussed above, the punched-out slugs created by are the end products of the process, and unused sheet metal is discarded or reused after the slugs have been obtained.
There are many other operations that follow, but differ from, the basic process. Some of these include:
No matter the type of hole-punching process used, it will result in quality parts at tight tolerances.
Different Types of Blanking Methods
While the fundamentals of the blanking process are simple, they have many variations, which we describe below:
Compound Die Stamping
This type of blanking is used to precisely manufacture complex steel parts. In this process, workers or automated equipment feed a steel strip through the stamping machine, which punches out a blank every three seconds. This simple, precise, and fast technique enables firms to produce steel components in bulk.
Continuous Strip Blanking
As implied by the name, continuous strip blanking continuously feeds metal substrates through a machine. This allows punching machines to produce uniform end products around the clock, with each product having the same characteristics of those before and after it. This process is a great way to develop coins, bottle caps, and medallions.
Progressive Die Stamping
Progressive die stamping uses coiled strips of thin flat metal as its base material. In this process, progressive die machines sequentially stamp, trim, and bend workpieces to make the finished parts, which exit the machine in conjoined strips. After performing this task, the machine separates individual parts from the strip, which results in the creation of several identical parts.
Square Sheared Blanking
Square sheared blanking is a fine process that uses specialized clamping tools to produce square-edged and contoured blanks. This process is a great way to create panels, casings, and any other component that requires a uniform square shape.
This process combines metal cutting and metal blanking procedures to create highly specialized blanks. When cutoff blanking, manufacturers blank metal sheets and then cut the metal at the sheets, allowing the production of long, flat pieces.
Best Materials to Use When Blanking
Ohio Valley Manufacturing performs blanking on carbon steel, stainless steel, and aluminum. Each material brings unique properties to the process, which we explore below.
Metalworkers use carbon steel to make industrial equipment and household tools like knives because of this material’s exceptional strength and hardness. Carbon steel’s hardness varies depending on the amount of carbon present within it, and the higher the carbon content, the harder the alloy is.
Carbon content in carbon steel ranges from 0.8% to 2.11%, and the typical value is about 1.5%. Carbon steel is more cost effective than other materials of comparable hardness, thus making it a popular raw material to use as a substrate.
Stainless steel has low carbon content but a large amount of chromium, which ranges from 10% to 30% of the final material. This chromium content makes stainless steel highly resistant to corrosion and heat.
Stainless steel may also incorporate other metals like aluminum, copper, and titanium to enhance various attributes, and even nonmetals like phosphorous and sulfur can be used to improve resistance to certain types of corrosive substances. Stainless steel is thus a versatile alloy that can take on a variety of uses depending on its composition.
Aluminum’s softness and flexibility make it very suitable. In fact, aluminum is the most common metal used to create industrial and household products because of this material’s low cost, ease of extraction, and properties like lightness, durability, and recycling potential.
For these reasons, many applications in the automotive, aerospace, energy, and packaging industries use aluminum in large quantities. Aluminum is a very cost-effective way to produce high volumes of components.
Quality Metal Blanking from Ohio Valley Manufacturing
Ohio Valley Manufacturing offers precision blanking services for clients from all industries. We accommodate all types of orders, from prototyping to low- and high-volume production runs. We’ve been in business for over 20 years and are adept at meeting the unique needs of our customers.
Contact us today for all your custom blanking requirements.