Drilling is a type of machining by separating particles with which special tools (drills) are used to make cylindrical holes in the workpiece. The tool performs the main rotational motion and a rectilinear shear motion which must be in the direction of the axis of rotation. Drilling in the narrower sense means making round holes (nut, screw, bore) using a cutting tool (drill), which also completely determines the diameter of the hole in a coarser tolerance. Drilling is performed on machine tools, mainly drills, where the main movement is circular continuous, and the shear movement (displacement) is rectilinear continuous which is performed at the same time as the main movement. The tool used is a drill bit determined by the number of cutting blades, the angle of the drill groove, the material of the drill bit, the geometry of the drill bit tip, the core and the geometry of the blade.
Marking or center hole is a process of machining a hole used before drilling to center the twist drill and guide it properly. It is also used to make sockets for shafts and shafts for centering and proper clamping during further machining on the shaft or shaft. The tool used is a drill.
Expansion is the process of drilling with a drill bit larger in diameter than the diameter of an existing hole.
Countersinking is the process of processing the input or output of a round hole. Inserts are cutting tools used to widen the inlet or outlet of the hole, and to achieve a more accurate shape of the existing holes. They cut like drills and are made with two, three or more cutting blades. Indentation is the rough processing of metal. We use them to process the front surfaces straight or at an angle. They are used for widening, countersinking screw heads, machining oblique ends of holes and for aligning raised workpiece parts. According to the form and purpose, the indentations are divided into:
- spiral or threaded countersinks,
- door recesses,
- conical countersinks,
- one-sided front indentations,
- special indulgences.
Reaming is the process of finishing a cylindrical hole. The accuracy of the dimension, geometric shape and surface roughness obtained after drilling is not satisfactory in most cases. They drilled cutting tools that are used for finishing holes and are used for fine machining of already existing holes, ie to improve the smoothness of the surface and achieve greater accuracy of drilled holes (seating).
Threading in a hole is the process of making spiral grooves in an existing hole. The notch enters vertically into the round hole with a certain number of revolutions, and a certain offset, which must correspond to the pitch of the thread.
Metals and non-metals can be processed by stamping. In the case of metals, steel, brass and aluminum sheets are most often processed. They can be in the form of plates, strips or ribbons and up to 6 mm thick. Steel sheets thicker than 6 mm must be additionally heated. The application of punches is in serial and mass production. With the correct use of materials and proper processing, a series of several thousand pieces can be made with one tool. Production time is much shorter resulting in high process productivity.