Turning is a method of cutting a workpiece on a lathe by rotating the
workpiece relative to the tool. Turning is the most basic and common cutting
method. Most workpieces with the rotary surface can be processed by turning
methods, such as inner and outer cylindrical surfaces, inner and outer conical
surfaces, end faces, grooves, thread, and rotary forming surface. Common lathes
can be divided into horizontal lathes, ground lathes, vertical lathes, turret
lathes, and imitation lathes, most of which are horizontal lathes.
Due to the development of modern science and technology, a variety of high
strength, high hardness engineering materials are more and more used, the
traditional turning technology is not competent or can not realize the
processing of some high strength, high hardness materials, but the modern hard
turning technology makes it possible and in the production of obvious
(1) High turning processing efficiency
Turning has higher efficiency than grinding. Turning often uses large cutting
depth, and high workpiece speed and its metal removal rate is usually several
times that of grinding. A variety of surfaces can be finished by clamping at one
time in turning, while many installation times are needed in grinding, so the
auxiliary time is short and the position precision between the machining
surfaces is high.
(2) Low cost of equipment input in the productivity of the same lathe
investment is significantly better than the grinding machine, its auxiliary
system cost is also low. For small batch production, turning does not require
special equipment, while large batch processing of high precision parts requires
good rigidity, positioning accuracy, and repeated positioning accuracy of CNC
(3) suitable for small batch flexible production requirements lathe itself is
a flexible processing method with a wide range of processing, lathe control is
simple and fast turning clamping, compared with grinding hard turning can better
adapt to flexible production requirements.
(4) Hard turning can make the parts get good overall machining accuracy
Most of the heat produced in hard turning is taken away by the cutting oil,
which will not produce surface burns and cracks like grinding processing. It has
excellent machining surface quality, and accurate machining roundness, and can
ensure high position accuracy between machining surfaces.
(1) coated carbide cutting tool
The coated cemented carbide tool is coated with a layer or multilayer coating
with good wear resistance on the carbide tool with good toughness. The coating
usually plays the following two roles: on the one hand, it has much lower
thermal conductivity than the tool matrix and the workpiece material, which
weakens the thermal effect of the tool matrix; On the other hand, it can
effectively improve the friction and adhesion of cutting process and reduce the
generation of cutting heat. Compared with cemented carbide tools, coated carbide
tools have been greatly improved in strength, hardness, and wear resistance.
(2) ceramic material tool
Ceramic cutting tools have the characteristics of high hardness, high
strength, good wear resistance, good chemical stability, good bond resistance,
low friction coefficient, and low price. When used normally, the durability is
very high, the speed is several times higher than that of cemented carbide,
especially suitable for high hardness material processing, finishing processing,
and high-speed processing.
(3) cubic boron nitride cutting tool
The hardness and wear resistance of cubic boron nitride are second only to
diamond, and it has excellent high-temperature hardness. Compared with ceramic
cutting tools, its heat resistance and chemical stability are slightly worse,
but its impact strength and crushing resistance are better. It is widely used in
the machining of hardened steel, pearLItic gray cast iron, chilled cast iron,
high-temperature alloy, etc. Compared with a cemented carbide tool, its cutting
speed can even be increased by one order of magnitude.