Drilling and boring are two methods of machining used in manufacturing. Both methods are used for creating or enlarging a circular hole in the material.
More about Drilling
Drilling is the cutting process of a material using a specially designed rotating cutting tool called a drill bit. The holes produced by the drilling are always cylindrical in shape and circular in the diameter.
Drilling process is simple. The drill bit is rotated by a drill and pressed against the material, where the tip of the drill bit cuts away the layers of material. By continually pressing against the material, a hole of a desired length can be created. Some specialized drill bits can create shapes other than cylindrical such as conic shapes. Drill holes have characteristic sharp edges on the entrance and burrs on the exit side.
A variety of drilling methods is used based on the material qualities, the hole size, and surface finish. Spot drilling, center drilling, deep hole drilling, gun drilling, trepanning, micro drilling, and vibration drilling are some that have their specific applications and characteristics.
More about Boring
Boring is the process of enlarging a hole that is already in the material; it may be a hole made by drilling or in the casting. Boring concerns the internal diameter and the surface of the hole rather than the depth of the hole. In this sense, it can be considered as a twin process of turning, where the outer diameter and the surface are the concerns.
Boring is done using a boring bar, which is a heavy metal bar with the tools fixed at the end. The method of turning the work piece or the boring tool is dependent on the application. However, boring machines come in many sizes, to fit with the industrial manufacturing requirements. The boring process on the cylindrical surface is known as the line boring. It can be either for achieving a greater tolerance and finish or for enlargement of the hole itself. The other type of boring is the back-boring, the process where the back of the hole inside an existing blind hole is cut to finish or extend.
Boring can also be done on milling machines and lathes. Boring is done typically in a vertical milling machine with the work piece held stationary and the tool bit rotating, and on the lathe, with the work piece rotating and tool bit stationary. Common examples of boring process are boring of the cylinders of internal combustion engines and boring of the gun barrels, but there are numerous applications.
What is the difference between Drilling and Boring?
• Drilling is the process of perforating a solid material surface using a drill bit to create a cavity. The surface of the drilling is rough, and the edges of the entrance may be rugged.
• Boring is the process of cutting the internal surfaces of an existing hole, where the goal may be enlarging the hole or to achieve higher tolerance and finish in the product.