Cutting tools include a variety of tools such as knives, grinding tools and abrasives, and are mainly used to remove excess material from blanks or workpieces to obtain a designed geometric shape. Whether it is the processing of molds or the mass production of workpieces, in CNC processing, all operations are inseparable from the participation of cutting tools, and different processing requirements and processing environments lead to different cutting tools.
Commonly used cutting tools include milling cutters, drills, taps, reamers, turning tools, hobs, etc. This article will briefly introduce these cutting tools for you.
Milling cutter
Cutting tools commonly used in machining centers and milling machines, the most representative of which are end mills called universal tools, which can efficiently cut flat surfaces, sides, grooves and slits of workpieces.
Drill
Cutting tool for drilling, often used in machining centers and drill presses. According to the diameter and depth of the hole, a variety of drills are subdivided, such as oil hole drills that can improve chip removal efficiency, and long gun drills suitable for deep holes.
Tap
A cutting tool used to cut threads (internal threads). Tapping a threaded hole is called “tapping”. It is an indispensable tool when machining mechanical parts with many threads.
Reamer
A tool used for finishing the inner diameter and surface roughness of drilled holes. Automobile engine parts, aircraft parts and other parts with relatively high precision often use a reamer to repair the hole to ensure the accuracy of the hole.
Turning tool
A cutting tool with a chipping edge at the top and one of the most widely used cutting tools today, often found on lathes and turning centers. It cuts into rotating workpieces to scratch metal surfaces.
Hob
Special tools used on gear processing machinery such as gear hobbing machines and gear cutting machines are mainly used to process gears or toothed workpieces.
Broach
The broach is a multi-tooth tool with high machining accuracy and cutting efficiency. It is widely used in mass production and can process various inner and outer surfaces. Broaches can be divided into various internal broaches and external broaches according to the surface of the workpiece to be processed. When using a broach to process, in addition to selecting the rake angle and relief angle of the tooth according to the workpiece material, and determining the size of the broach according to the size of the workpiece processing surface (such as the diameter of the round hole), two parameters need to be determined:
(1) Tooth lift angle af [that is, the difference between the radius or height of the front and rear two teeth (or tooth groups)];
(2) Tooth pitch p [that is, the axial distance between two adjacent teeth].
Gear cutter
Gear cutters are tools used to machine gear tooth profiles. According to the working principle of the tool, the gear is divided into a formed gear tool and a generated gear tool. Commonly used form gear cutters include disc gear milling cutters and finger gear cutters.
Commonly used generating gear cutters include gear shaping cutters, gear hobs and gear shaving cutters. When selecting gear hobs and gear shapers, the following points should be paid attention to:
(1) The basic parameters of the tool (modulus, tooth profile angle, addendum height coefficient, etc.) should be the same as the gear to be processed.
(2) The accuracy grade of the tool should be equivalent to the accuracy grade required by the gear being machined.
(3) The direction of rotation of the tool should be the same as that of the gear being machined as much as possible. When hobbing spur gears, a left-handed tooth cutter is generally used.
Tool material
The commonly used materials used to make cutting tools are tool steel, high-speed steel, cemented carbide and diamond.
“Hardness” and “toughness” are two important indicators of tools, which vary from material to material, and are generally selected according to cutting scenarios and working conditions.
Hope the above content can help you.
