There is a different operation performed with the drilling machine as the manufacturing process involves holes to be accomplished. Different drill bits must be required to carry out the operation of various types.
Most people today think drilling is performed only on soft materials like wood, but the fact is that drilling is performed on hard materials like metal as far as the drill bit is harder than the workpiece. Learn about drilling machines here
Now, let’s go deep to discuss the various types of drilling operations!
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Drilling Operations
The types of drilling operations are drilling, core drilling, step drilling, boring, reaming, counter boring, counter sinking, spot facing, tapping, and trepanning.
Drilling operation
This is the most common operation done with a drilling machine. It is applied when a circular hole of any size is needed in a workpiece. Although one can use a lathe machine for drilling.
Core drilling
Cores are used when sand casting is made to displace the metal where metal is desired. The molten metal flows around the core and after it solidifies the casting is removed from the mold and the holes are created on the core spaces. The hole here is quite rough and will require a heavy body drill to clean the holes.
Step drilling
In this drilling operation, more than one diameter can be ground on the drill body, which serves as an extra operation
Boring
Boring is done to enlarge the diameter of an existing hole of a part. The tool used in this operation is generally a single-point cutting tool.
Reaming
This is the finishing of a drilled hole in order to obtain the specific size, and fine surface, and make the diameter the same size from end to end. A sufficiently smooth hole is desired and called will be called a precision hole as greater accuracy is required.
Read more: Power-feed and hand-feed drilling machine
Counter boring
Counter boring is when another drill bit of a larger size than the first will be used to open a wider hole. It is said to be used as a counterbore when the operation is done on a drilling machine. The small diameter on the end of the tool known as the pilot keeps the counterbore concentric with the original hole. This pilot is interchangeable with other different sizes to fit the various sizes of holes.
Counter sinking
The drilling machine performs this operation to produce an angular surface at the end of a hole. It is made of different angles and diameters sizes. The angle size depends on the countersinking purposes. Countersink for a flathead screw requires an 82-included angle, keeping the center hole at an angle of 60. Different rivet head types included angles from 90 to 145-degree
Spot Facing
Spot facing is done in order to create space for a bolt head, washer, or nut. It is usually performed on casting, machining a flat or circular surface around the workpiece. However, counterbore may be used for the operation.
Tapping
This drilling machine operation is done by creating a tapped (threaded) hole on a workpiece. It is achieved by producing a non-tapped hole in the material, using a specified size drill bit. A tapping attachment will then be used to create the threading using a standard drilling machine.
This tapping attachment is held in the spindle of the drill press, which accurately centers on the drilled hole.
Trepanning
Trepanning is a hole-making operation, producing an annular groove making the center a solid cylindrical core. In this operation, a cutter consisting of one or more cutting edges is placed along the circumference of a circle in order to achieve the annular groove. Trepanning is said to be feasible if the hole has a diameter of more than 50mm.
That is all for this article, where I explained the various drilling operations. I hope it was helpful, if so, kindly share with others. Thanks for reading, see you around!