This month we continue our exploration of how we finish processed steel. With methods like plasma cutting, polishing, press brake cutting, sawing, and shearing, an experienced fabricator can create the perfect product to suit your needs.
Plasma cutting is an impressively precise and powerful way to finish processed steel. The cuts created are clean and meticulous, and the need for secondary processing is minimal. The method is efficient and relatively inexpensive. Plasma cutting can be used on even heavy metal plate, including stainless steel, alloy steel, carbon steel, brass, aluminum, and copper.
The process works by cutting through the metal in question with an accelerated stream of hot plasma. The plasma cutter expels a high-velocity stream of pressurized gas through a nozzle, and an electric arc created between the metal and an electrode within the nozzle ionizes the gas, forming an electrically-conductive channel of plasma. This cuts away at the molten metal. We perform plasma cutting at our Cd’A Metals and Norfolk Iron & Metal locations.
You cannot really finish processed steel until the finishing touch has been applied: polishing. Polishing is the process of using abrasives attached to a flexible backing to smooth, buff, and improve the overall surface finish of the material being processed. Abrasives serve different functions depending on their grit. Low-grit abrasives, rated 60 or 80 for example, remove gouges or nicks in the metal’s surface. On the other hand, high-grit abrasives at values of 120 or 180 refine the surface of the material.
Usually a series of abrasives of increasing grit are employed to enhance the physical appearance of your finished product. Polishing also improves the sanitary benefits of the material, making it an essential process for products destined for the food industry. We offer No. 3, No. 4, No. 4 Fine, No. 6, No. 8, and specialty finishes, all applied in-house at our Metalwest locations.
One step on the road to finish processed steel is shaping it into specified configurations. This is accomplished using a press brake. Press brakes can be operated hydraulically, mechanically, pneumatically, or electrically, and they are usually long and narrow so that large pieces of sheet metal can fit inside them. The metal is sandwiched between a punch and a die, and then pressure is applied to bend the metal.
Tonnage refers to the amount of force a press brake can apply, and the metric is how press brakes are rated. 100 to 300 tons is common, but tonnages of 3000 tons are not unheard of. Such press brakes have to be massive, as long as 50 feet long. In addition to different amounts of force, different press brakes also work at different speeds. The metal being molded makes a great deal of difference to the settings used.
Hydraulic press brakes provide high amounts of force, while electronic press brakes reduce the risk of leaks and minimize operating costs. They also work more quickly and accurately while taking up less space. Press brakes are used in a number of applications to finish processed steel, including automotive panels, furniture, airframes, and metal containers. We manage our press brake operations at our Norfolk Iron & Metal facilities.
Sawing is a way to finish processed steel, aluminum, titanium, copper, brass, bronze, and nickel alloys by cutting larger pieces into smaller ones. It is used across many industries, including architecture, aerospace, food processing, packaging, and biotechnology. We perform sawing at all our facilities: Cd’A Metals, Metalwest, and Norfolk Iron & Metal.
There are two major forms of sawing commonly used in manufacturing applications: band saw cutting and circular saw cutting. Circular saws spin as they cut but are designed to be rigid to reduce vibrations. This results in quick cuts that are still highly precise.
On the other hand, band saws are long and straight with metal teeth arranged to suit necessary functions. These teeth are bent slightly, and the cuts they make, while remarkably straight and uniform, are slightly wider than the blade itself.
Sawing can handle a high volume of cuts while reducing material waste due to closer tolerance cutting. The method offers rapid turnaround and high quality cut finishes. This generally cuts down on the amount of further finishing necessary to finish processed steel.
Shearing is a metal-cutting process that results in smaller pieces of sheet metal being cut out of larger flat or rolled stock. A shear machine moves the metal through, making straight cuts with large, sharp blades. The cuts made by shearing are clean and quick as they require no additional burning or melting of the metal. Because the blades are affixed and controlled by a squaring arm, the process has been compared to using large scissors.
Though shearing is better for softer metals like aluminum, bronze, and brass, it can be used to finish processed steel with higher-powered machinery. If the process is performed incorrectly, it will deform the metal. Shearing accommodates a high volume of cuts with very little material waste. We offer shearing services at our Metalwest and Norfolk Iron & Metal locations.
Metal provides a wonderfully diverse starting point for many of the products we interact with on a daily basis. There are hundreds of ways to finish processed metal, methods for cutting, boring, etching, and smoothing. Over the next few months, we will be elaborating on some of the methods for processing metal that we employ within the Norfolk Iron & Metal Group.
Preparing to weld requires a lot of treatments. One of those is often beveling. Beveling is the process of cutting a sloping edge into two metal pieces so the joining edges have a greater surface area in contact. The precision of the diagonal cut makes for a strong weld. The fact that the way to finish processed metal also reduces the thickness of the two pieces’ butting endings further improves weld fusion.
A double bevel further strengthens the joining of the pieces by reducing the risk of a gap in the point of the V-shaped gap. Even without the double bevel, the introduction of a bevel makes the risk of the centerline cracking significantly less. The seam is also cleaner.
Beveling creates emissions, which means that it is important to wear the correct safety gear when handling or around beveling equipment. Our Cd’A Metals component of the Norfolk Iron & Metal Group can complete your beveling efficiently and quickly, just what you need for successful welding.
Blanking is a form of stamping out a piece of metal from a larger coil of sheet metal. The material that is punched out of the sheet is the piece (or “blank”) that is then used in further applications. The sheet metal is fed continuously in a coil between a press and die where blanks are cut out in a minimally wasteful way.
Blanking is a highly customizable way to finish processed metal. It is mostly commonly used for punching out pieces of iron, copper, aluminum, carbon steel, and stainless steel. Blanking is beneficial in its ability to level and cut-to-length slit and smaller coils in a way that significantly reduces waste. We complete all blanking projects in-house at our Metalwest facilities.
Similar to blanking, hole punching is a method for puncturing through sheet metal. The metal is fed into a press with dies and other tools on the other side of the sheet. The press, supported by the dies, puts pressure on the metal, causing plastic deformation until the metal is eventually perforated cleanly through. Unlike blanking, the piece that is then further processed is the one with the hole, not the blank created in the process.
Blanking is a way to finish processed metals such as copper, aluminum, iron, brass, and stainless steel. The punches used are usually specific to customer specifications and depend on the application the metal will be subsequently used for, be it engineering, automotive, manufacturing, or textile applications. It should be noted that hole punching is most effective on material that is 25–30 mm thick. Our Cd’A Metals facilities manage all hold punching applications.
Laser cutting is a way to finish processed metal that utilizes a focused high-energy laser beam to cut sheet or plate metal to intended specifications. The directed beam follows the programmed design (called a G-code) in a 2-dimensional profile, burning or melting through the metal, usually stainless steel, carbon steel, aluminum, or brass.
Laser cutting offers the option to make cuts highly precise, with low cut widths as small as 0.1 mm depending on the thickness of the material being cut. Occasionally the process also involves a high-pressure stream of gas to blow the molten material out of the bottom of the material being processed. This removes the waste from the cut area. Alternatively, the laser can simply vaporize the excess.
One of the advantages of laser cutting is that parts do not generally require significant post-processing other than the occasional deburring in the event of leftover slag. The process is also automated, quick, and highly precise. It can be used to finish processed metal of nearly any variety. It is, however, usually limited to making cuts of 25mm deep, so laser cutting is best suited to thin sheet material if fabricators want a high-quality cut.
Laser cutting is not without its drawbacks, however. The process requires a lot of power and can create noxious and dangerous fumes. The initial setup is expensive, and the maintenance costs are also high. We manage laser cutting at both our Cd’A Metals and Norfolk Iron & Metal sites.
Leveling is the process of unrolling metal coil and cutting it into lengths. The parent coil is unwound, leveled, and cut into cross sections. These newly cut pieces are then stacked and packaged. The point of this way to finish processed metal is to convert coil into sheet. Technology is at the point where tolerances during the process can be very tight, ensuring that quality is consistent and meets specifications.
These tight tolerances also accommodate minimal waste along the metal supply chain, saving customers time and money. We manage leveling and the cut-to-length process at both our Metalwest and Norfolk Iron & Metal properties, occasionally even processing non-ferrous material. Our customers can expect cut-to-length and leveling requirements from 28 gauge to 10 gauge carbon steel.
We deliver a wide variety of materials, including various grades of aluminum and stainless steel, as well as cold rolled, hot rolled, and wear resistant steel.
We saw, laser, plasma, or oxy-fuel cut and press brake form material to make the parts you need.