Turning on lathes is one of the most popular technological methods for producing various parts for complex, multi-part mechanisms in mechanical engineering. To improve the quality characteristics and increase the production rate of all kinds of elements, it is necessary not only to optimize all the operations performed, including the selection of optimal rotation and feed modes, but also a reasonable choice of material for the workpieces clamped in the chuck. In most cases, the best results can be obtained calibrated steel circle, which has all the necessary properties for this.
Among the most important features for practical application, the following should be highlighted separately:
- At the starting stage, the existing irregularities in the workpiece, causing an imbalance in the mass distribution, pose a serious danger to the machine tool. Since the developed centrifugal force is directly proportional to it, as well as to the square of the rotation speed, the latter has to be reduced to a minimum until an ideal cylinder is obtained during the chip removal process. The material described is symmetrical relative to the central axis due to the calibration performed by the manufacturers, so it can be processed at maximum speed right from the start without the risk of damaging the shaft or bearings of the machine.
- The greater the hardness and viscosity of the material, the more difficult it is to process it with cutting tools. The structural steel used as the raw material for the described products has a moderate value for both of these indicators, so it is quite easy to remove chips even with the simplest inexpensive cutters.
- Another important characteristic for turning operations is thermal conductivity, due to which excess thermal energy is removed from the working area. If its value is insufficient, in order to avoid the occurrence of restructuring of the metal crystal lattice due to overheating, it is necessary to use cooling emulsions, which is very expensive and not very convenient. For the described material, cooling by ambient atmospheric air is quite sufficient without supplying additional heat carriers to the cutting area.
Everything written above applies not only to calibrated steel circle, but also to some other types of black rolled metal products made of structural steel. For example, calibrated steel hexagon It differs only in the geometric shape of the cross-section, which is specially created for the production of bolts and nuts with hexagonal heads and does not in any way affect the factors listed above.
Analogues of calibrated steel circle
Of the other analogues of a calibrated steel circle, it is worth considering two in detail, each of which has significant differences both in properties and in purpose.
Tool steel circle
For the production of hand and electric tools, as well as working parts for machine tools, materials with higher strength and hardness than the processed ones are required, otherwise, when they come into contact, their wear will become proportionate, and it will not be possible to carry out the process over a long period of time. Due to these considerations, tool steel circle most often made from various grades of high-carbon or hardenable steel. In the first case, the hardness is due to the high content of hard iron carbide, which imparts not only hardness to the product, but also increased brittleness, which is why, in order to avoid chipping and cracking, it is necessary to avoid impact loads, limiting ourselves to only smoothly cutting a thin layer of metal in one pass, which is typical, for example, for round files. The second type of raw material receives improved characteristics not due to the initially existing chemical composition, but due to the targeted restructuring of the atomic lattice due to the thermal effect on the sample by changing the temperature in a certain sequence. This approach allows us to obtain chisels, picks of jackhammers and other parts that can withstand impacts.
Stainless steel circle 08Х18Н10
Manufactured from high-alloy steel, 08Х18Н10 stainless steel circle contains a large amount of chromium and nickel. The first of the listed metals gives it greater hardness and the ability to resist the effects of chemically active substances, and the second provides exceptional heat resistance. These valuable qualities have to be paid for by a significant increase in cost price and difficulties arising during turning, but the resulting parts work well at high temperatures in an aggressive environment.