Metal Cutting Methods
As per the Usage and applications of customers requirement metals are cut into desired shape & size; having specific design. So its important to employ PRECISE METAL CUTTING METHODS to make sure that the metal fabrication meets customers’ specifications with versatility and flexibility. In order to achieve the desired design from metals , it is essential to apply a range of competitive devices and measures to cut the metals.
In the starting of days, metals were handled by some hand-driven machines such as hacksaws, chisels and shears. But as time proceeds, apart from these manual tools and smaller cutting devices that can be hand operated, many advanced Accurate and precise cutting tools were invented and innovated, in order to produce better results in lesser time. There are many types of metal and each requires different metal cutting techniques. Because of this, there are a variety of methods available to cut metal materials. The method you choose for your project will depend on the type of metal being used, the level of precision that is required and the intended use of the fabricated part and project.
Definition of Metal Cutting:
Metal cutting is “the process of removing unwanted material in the form of chips, from a block of metal, using cutting tool”. A person who specializes in machining is called a machinist. A room, building or company where machining is done is called a Machine Shop.
The following are the metal cutting methods listed below, in order to deal with more robust and challenging projects.
Hand Tools for Cutting Metal Manually
For smaller cutting jobs, hand tools, including hand shears and hacksaws may be used for cutting metal into the desired shape. This cutting method is best suited for projects using more pliable metals, such as thinner-gauge aluminum. Using hand tools to cut metal is not recommended if the metal must be cut into extremely small pieces because the force needed to cut the metal may simply break it, instead of cutting it as intended.
Chisels can also be used to remove excess metal and to make a shape more precise. Depending upon the job, you may opt to use a cold chisel, with a sharpened edge or a hot chisel, which is heated before being hammered through metal.
Types of Metal Cutting Processes (Operations):
Machining is not just one process; it is a group of processes. There are many kinds of machining operations. Each of which is specialized to generate a certain part geometry and surface finish quality.
Some of the more common cutting processes are shown in below Figure
Types of Metal Cutting Process
(i) Turning:
Turning is used to generate a cylindrical shape. In this process, the work piece is rotated and cutting tool removes the unwanted material in the form of chips. The cutting tool has single cutting edge. The speed motion is provided by the rotating work piece, and the feed motion is achieved by the cutting tool moving slowly in a direction parallel to the axis of rotation of the work piece.
(ii) Drilling:
Drilling is used to create a round hole. In this process, the cutting tool is rotated and feed against the work piece fixed in a holding device. The cutting tool typically has two or more cutting edges. The tool is fed in a direction parallel to its axis of rotation into the work piece to form the round hole.
(iii) Boring:
Boring is used to enlarge an already drilled hole. It is a fine finishing operation used in the final stage of product manufacture.
(iv) Milling:
Milling is used to remove a layer of material from the work surface. It is also used to produce a cavity in the work surface. In the first case it is known as slab-milling and in second case it is known as end- milling. Basically, the milling process is used to produce a plane or straight surface. The cutting tool used has multiple cutting edges. The speed motion is provided by the rotating milling cutter. The direction of the feed motion is perpendicular to the tool’s axis of rotation.
(v) Cutting-Off:
Cutting-off is used to cut the metal into two parts. In this operation, the work piece is rotated and cutting tool moves radially inward to separates the components.
Using Machinery to Cut Metal
For larger projects or those that use thicker or more robust metals, manual cutting is not always practical. There are numerous machine-based metal cutting methods to choose from, based on your metal cutting needs.
- Grinder – For projects that require the finished part to be extremely smooth, a grinding machine may be your tool of choice. Using a rotating blade or wheel made of an abrasive material; a grinder uses friction to wear down the surface of the metal until it is smooth, similar to sanding wood.
- Lathe – Using a sharpened cutting tool against a rapidly spinning piece of material, a lathe will cut a piece of metal to its desired shape. This machine is very common in the machining industry because it allows for a higher degree of precision.
- Punch – This machine uses an extreme amount of pressure to force sharpened blades into or through metal to cut it into the shape desired. The amount of pressure generated by a machine punch is far greater than any human worker could produce, thus this cutting method is suitable for metals that are more robust. Some machine punches are capable of up to 1,000 hits per minute, making this cutting method very productive.
- Water jet – Using water or water mixed with an abrasive compound, this machine directs an intense and concentrated stream into metal and cuts it. This method is best suited for metals that may be sensitive to extreme heat or temperature changes because it does not use heat in the process.
- Flame and plasma – This process is similar to a water jet, but instead a flammable gas is pumped through a torch to create an intense hot flame. The flame then cuts the metal by burning and melting it. Flame torches, such as oxyacetylene torches are very efficient for cutting. Plasma cutters are known for their high degree of precision because they burn much hotter.
Greater Precision in a New Method of Metal Cutting
Laser cutting is one of the newest and most exciting methods in cutting technology. These cutters apply an intense beam of light to the metal, heating it past its melting point, and then cut through the metal. A laser cutter is able to concentrate light onto a very small area, which makes this method suitable for projects that require a very high degree of precision. However, this method is slower and more expensive than other methods of metal cutting.
Article Source : alliantmetals.com ; yourarticlelibrary ; mainland machinery
Image Source : Metcera