(1) Classification of tools
According to the processing method and specific use, the tool is often divided into several types such as turning tools, hole making tools, milling cutters, broaches, thread cutters, gear cutters, automatic line and CNC machine tool tools and reamers.
Tools can also be classified in other ways,
For example, according to the materials used, it can be divided into high-speed steel tools, cemented carbide tools, ceramic tools, cubic boron nitride (CBN) tools and diamond tools;
According to the structure, it is divided into integral tools, insert tools, clamp tools and composite tools, etc.;
According to whether it is standardized, it is divided into standard tools and non-standard tools.
(2) Introduction to commonly used tools
1 turning tool
Turning tools are one of the most widely used tools in metal cutting without using signatures. It can be used to process external circles, end planes, threads, internal holes on lathes, and can also be used for grooving and parting, etc. In terms of structure, turning tools can be divided into integral turning tools, welded prefabricated turning tools and turning tools with mechanical clamping blades. The turning tools of mechanical clamping inserts can be divided into machine tool turning tools and indexable turning tools. The cutting performance of mechanical clamping turning tools is stable, and workers do not have to sharpen the tools, so they are more and more used in modern production.
2-hole machining tool
Holemaking tools can generally be divided into two categories:
One is the tool that processes the hole from the solid material, which is commonly used as a twist drill, center drill and deep hole drill;
The other type is a tool for reprocessing existing holes on the workpiece, which is commonly used for reaming drills, reamers and boring cutters.
3. Milling cutter
Milling cutter is a widely used multi-edged rotary tool, and there are many types of it. According to the application, it is divided into:
1) For processing planes, such as cylindrical plane milling cutters, end milling cutters, etc.;
2) For processing grooves, such as end mills, T-cutters and angle milling cutters;
3) Milling cutters for processing forming surfaces, such as convex semicircular and concave semicircular milling cutters and milling cutters for processing other complex forming surfaces. The productivity of milling is generally high, and the machining surface roughness value is larger.
4 broaches
Broach is a kind of multi-tooth tool with high machining accuracy and cutting efficiency, which is widely used in mass production and can process various internal and external surfaces. Broaches can be divided into two categories: internal broaches and external broaches according to the different surfaces of the workpiece to be processed. When using broach machining, in addition to selecting the rake angle and rear angle of the cutter teeth according to the workpiece material, and determining the broach size according to the size of the workpiece machining surface (such as the diameter of the round hole), two parameters need to be determined:
(1) Tooth lift angle af [i.e., the difference between the radius or height of the front and rear cutter teeth (or tooth group)];
(2) Tooth pitch p [i.e., the axial distance between two adjacent cutter teeth].
5. Threaded cutter
Threads can be machined by cutting and rolling.
6. Gear cutters
A gear cutter is a tool used to machine the tooth profile of a gear. According to the working principle of the tool, gears are divided into forming gear cutters and developed gear cutters. Commonly used forming gear cutters include disc gear milling cutters and finger gear cutters, etc. Commonly used gear cutters include shaper cutters, gear hobs and shaving cutters. When choosing gear hobs and shaper cutters, the following points should be noted:
(1) The basic parameters of the tool (modulus, tooth shape angle, tooth top height coefficient, etc.) should be the same as the processed gear.
(2) The accuracy level of the tool should be equivalent to the accuracy level required by the gear to be processed.
(3) The rotation direction of the tool should be the same as that of the processed gear as much as possible. When hobbing spur gears, a left-handed tooth cutter is generally used.
7. Automatic line and CNC machine tools
In general, the cutting part of this kind of tool is not much different from the general tool, but in order to adapt to the characteristics of CNC machine tools and automatic line processing, higher requirements are put forward for them.
CNC tools have formed three major systems: turning tool system, drilling tool system and boring and milling tool system.
(3) Types and applications of commonly used tools
1. Turning tools
The general use of turning tool tip types are as follows:
(1) Rough turning tool: It is mainly used to cut a large number of excess parts to make the diameter of the working object close to the required size. The surface gloss is not important for rough turning, so the turning tip can be ground into a sharp peak, but the peak usually has a slight roundness to avoid breakage.
(2) Fine turning tool: The workpiece turned by this blade has a very smooth surface gloss, and the round nose of the fine turning tool is generally larger than that of the rough turning tool.
(3) Round nose turning tool: It can be applied to many different types of work is a common turning tool, which can be turned left and right when the top surface is smoothed, and can also be used to turn brass. This turning tool can also form a rounded surface on the shoulder angle, and can also be used as a finishing turning tool.
(4) Cutting turning tool: only the end of the cutting work, this turning tool can be used to cut the material and the turning groove.
(5) Screw turning knife (tooth knife): used for turning screws or nuts, according to the form of threads, divided into 60 degrees, or 55 degrees V-shaped tooth knife, 29 degrees trapezoidal tooth knife, square tooth knife.
(6) Boring turning tool: used to turn drilled or cast holes. The purpose is to achieve a light size or a straight hole surface.
(7) Side turning tool or side turning tool: used to turn the end face of the work, the right turning tool is usually used at the end of the finishing axle, and the left turning tool is used for the left side of the shoulder of the finishing turning.
2
Due to the different processing methods of the workpiece, different blade shapes are used, which can generally be divided into:
(1) Right-hand turning tool: from right to left, turn the outer diameter of the workpiece.
(2) Left hand turning tool: from left to right, turn the outer diameter of the workpiece.
(3) Round-nosed turning tool: the blade is arc-shaped, which can be turned in the left and right directions, and is suitable for turning with fillet or curved surface.
(4) Right turning tool: turning the right end face.
(5) Left turning tool: turning the left end face.
(6) Cutting knife: used for cutting or grooving.
(7) Internal turning tool: used for turning internal holes.
(8) External thread turning tool: used for turning external threads.
(9) Internal thread turning tool: used for turning internal threads.
2. Hole making tools
One is a tool that makes a hole from a solid material; The other type is a tool that reprocesses an existing hole in the workpiece.
Commonly used drill bits mainly include twist drills, flat drills, center drills, deep hole drills and nest drills. Reamers and countersins cannot drill holes in solid materials, but they are customarily classified as drill bits.
A drill is a tool used to drill through or blind holes in solid materials and reaming existing holes
According to the use of reamers, there are hand reamers and machine reamers, and machine reamers can be divided into straight handle reamers and taper handle reamers. The hand one is straight-handled.
There are many types of reamers for different purposes, so there are many standards for reamers
The reamer is used to reaming the hole that has been drilled (or reamed) on the reaming workpiece, mainly to improve the machining accuracy of the hole, reduce the roughness of its surface, and is a tool for the finishing and semi-finishing of the hole
3. Milling cutter
Types of milling cutters and their uses:
It is broadly divided into:
1. Flat-head milling cutter, rough milling, removal of a large number of blanks, small area horizontal plane or contour precision milling;
2. Ball nose milling cutter, semi-finish milling and finish milling of curved surfaces, small chamfers can be fine milling of steep faces/straight walls
3. Flat-head milling cutter with chamfering, which can be used for rough milling to remove a large number of blanks, and can also be fine milling for small chamfers on the flat front (relative to the steep surface).
4. Forming milling cutters, including chamfering cutters, T-shaped milling cutters or drum cutters, toothed cutters, and internal R cutters.
5. Chamfering cutter, the shape of the chamfering cutter is the same as the chamfer shape, and it is divided into milling cutters with rounding chamfers and oblique chamfers.
6. T-shaped cutter, can mill T-shaped slot;
7. Toothed cutter, milling out various tooth shapes, such as gears.
8. Coarse leather cutter, rough milling cutter designed for aluminum-copper alloy cutting, can be processed quickly
4. Broaches
Inner broach is used to process the inner hole surface of various profiles, and its broach name is generally determined by the shape of the hole to be processed, such as round hole broach, four, hexagonal broach, keyway broach, spline broach, etc.
The inner broach can also process spiral internal splines, internal gears. The hole diameter that can be machined by the inner broach is usually 10-120mm, and it can be processed to 5-400mm in special cases, and the groove width of broaching is generally 3-100mm, and the length of the hole is generally not more than 3 times the diameter, and it can reach 2m in special cases.
External broaches are used to process the outer surface of various baking rooms, such as planes, forming surfaces, grooves, complex tenons and tenons in steam turbines to replace milling, planing, grinding and other processing of these parts, especially suitable for some parts in mass production such as automobiles, motorcycles, tractors, etc.
Broaches can be divided into two categories: integral and combined (assembled) according to the mechanism, the inner broach of the center specification is made into a monolithic type, and the inner broach of large size and most of the external broaches are mostly made into a combined type.
According to the broach tooth material, it is divided into: high-speed steel broach and cemented carbide broach.
5. Threading cutter
Threading tools are used to process threads on the surface of parts, and it comes in many forms.
Depending on the type of thread, the accuracy and the production batch, different methods and threading tools can be used to process threads.
According to different processing methods, threading tools can be divided into two categories: cutting method and rolling method.
Cutting thread tools: thread turning tools, taps, dies, thread milling cutters, thread cutting heads with automatic opening and closing.
Threading tools for rolling: thread rollers and thread rolling plates.
6. Gear cutter
Gear cutter refers to a tool that processes the tooth profile of a gear.
According to the shape of the gear to be processed
Involute gear cutters
(1) Processing cylindrical gear cutters: such as gear milling cutters, broaches, hob cutters, shaper cutters, shaving cutters, etc.;
(2) Processing worm gear tools: such as worm gear hobs, flying knives, worm gear razors, etc.;
(3) Processing bevel gear cutters: such as gear planer cutters, bevel gear milling cutters, etc.;
Non-involute toothed cutters
Such as cycloid gear cutters, spline hobs, sprocket hobs, etc.
7. Automatic line and CNC machine tools
CNC tools have formed three major systems: turning tool system, drilling tool system and boring and milling tool system.
Turning tools: external circle, internal hole, external thread, internal thread, grooving, cutting end face, cutting end face ring groove, cutting off, etc.
Drilling tools: small holes, short holes, deep holes, tapping threads, reaming, etc.
Boring tools: rough boring, fine boring and other tools,
Milling tools: facet milling, end milling, side and face milling and other tools.
It is widely used in: CNC machine tools, machining centers (MC), flexible manufacturing cells (FMC) and flexible manufacturing (FMS).