SU1685610A1 - Method for mechanical machining by rotating tool - Google Patents

Description

one

(21) 4712639/08

(22) 06/29/89

(46) 10/23/1. Bul №39

(71) Novopolotsk Polytechnic Institute. Leninsky Komsomol of Belarus

(72) H. N. Popok and M. L Kheifets (53) 621.941.2 (088.8)

(56) Lizheritsin P.I., Borisenko A.V., Dryotin I. G., Lebedev V. Ya. Rotational cutting of materials. - Minsk: Science and technology, 1987, pp. 22-30.

(54) METHOD OF MECHANICAL PROCESSING BY ROTATING TOOL

(57) The invention relates to the machining of materials and can be applied in mechanical engineering in the processing of difficult-to-work materials with heating. The purpose of the invention is to improve the quality and productivity of processing for

by reducing the heat stress in the cutting zone and leveling the temperature along the cutting edge of the tool. In the case of the tool 2 is placed a closed heat pipe 3 with coolant 5. During processing, the tool 2 is affected by heat flow. In the heat pipe 3, an evaporator is formed, from which the coolant 5 flows to the condenser, where it gives off heat and returns at a speed Vm. The heat pipe 3 is rotated at a speed of Vmp Vm, which reduces the heat intensity of the process and shifts the capacitor to the optimum position. The tool 2 is rotated at a speed Vu 5: Vmp, as a result of which the tool does not overheat. In the cutting zone, it is not subjected to rapid cooling at the exit and rapid heating at the entrance to the cutting zone. 1 il. 1 tab.

WITH

WITH

The invention relates to the machining of materials with rotating tools and tools with internal cooling and will find application in machine-building production in the processing of difficult-to-work materials with heating.

The aim of the invention is to improve the quality and productivity of processing by reducing the heat stress in the cutting zone and leveling the temperature along the cutting edge of the tool.

The drawing shows a diagram of the cutting process.

The cutting is carried out with a rotating tool with a heat pipe, through which the workpiece 1 and the tool 2 are conveyed by rotational movements at speeds V and

Vu around the intersecting axes and relative to the movement of the feed with speed Vs In the tool body 2 near the cutting edge is placed a heat pipe 3 with a wick 4 and coolant 5. During processing, the heat flow Q affects the tool 2 in the cutting zone (heat source). pipe 3, in the immediate vicinity of the heat source, an evaporator is formed, from which the coolant 5 flows (indicated by an arrow) in the vapor phase to the condenser, where it returns heat q and returns in the liquid phase through a wick 4 capillary with speed Vm The heat pipe 3 is rotated at a speed Vmp Vm, which results in a decrease in the thermal stress of the process and a displacement of the capacitor with the drain of the geple q into optimum O 00 (L O

about

cooling position. The tool 2 is rotated in the same or opposite directions with respect to the pipe 3 at a speed Vu SVmp, as a result of which the tool does not overheat in the cutting zone and is not subjected to rapid cooling on exit and sharp heating when entering the cutting zone.

An example of the implementation of the method of machining rotating tools.

Workpieces made of steel 50 with a diameter of 0.1 m and a rotating tool made of high-speed steel R6M5 with a diameter of 0.055 m without a heat pipe (prototype) and with a heat pipe (the proposed method) were machined on a 16K20 turning-cutting machine with a device for rotary cutting.

The heat pipe was made in the form of a closed ring with a radius of 025 m from a copper pipe with an external diameter d of 1-0.025 m and an internal diameter of 022 m, and water was used as the coolant. The limiting heating temperature of the pipe was set equal to 200 ° C (473 ° K), since When this temperature was exceeded, undesirable decomposition of the lubricant in the bearing unit of the rotary tool occurred. The pipe had a wick, with a thickness of 001 m, consisting of five layers: a grid of copper wire with a thickness of 0.0001 m and cellularity. Wick cross-sectional area F l (di-do2), 5 m2, where. Porosity wick E - 1 - rNd / 4 0.6. The density of water at 473 ° K p 860 kg / m3. The heat of vaporization of water, 92x x 10J j / kg. The maximum power transfer factor for the described pipe W.M (7). Maximum local axial flow

Q

QI.

100

 1270 W

I -0,025 Liquid speed in capillaries wick

Q

CF / 5L

1270

0.6-7.5-10

, 017 m / s

860 1.92 10 °

Then the frequency of rotation of the heat pipe should not exceed the value

p60 Vm 60-0.017 2-7TR 2 L - 0.025

 6.5 rpm

The speed or frequency of rotation of the tool is set not lower than the frequency of rotation of the pipe in order to ensure optimal operation of the heat pipe.

and efficient heat removal from the cutting zone, as well as not reducing the processing performance. When machining with a tool rotation speed lower than the rotation speed of the pipe and above the specified speed

0 heat carrier, 017 m / s /, the well-known variant with a fixed heat pipe, which does not provide temperature leveling along the cutting edge, will be realized.

5 The reliability of processing was determined as a result of standard tests on the tool operation time until catastrophic wear, determined by thermal fatigue of the cutting edge. The quality of processing was determined by measuring the roughness of the machined surface of the part on a Model 252 profilograph-profilometer. Modes and results of comparative tests of the proposed method and

5 prototype methods are presented in the table. The frequency of rotation of the tool to check the position of the ratio of the speeds of movement of the coolant, heat pipe and tool was set

0 equal to, below and above the speed of movement of the coolant. As can be seen from the table, the use of a rotating tool with a heat pipe provides, over the entire range of cutting mode, an increase in tool life and a reduction in the surface roughness of the part by a factor of 1.5 compared with a tool without a heat pipe. This effect is achieved by reducing the temperature in the cutting zone and leveling.

0 temperature along the cutting edge of the tool. Moreover, the cooling effect is most noticeable at the tool rotation frequency equal to the speed of the heat transfer medium (durability 60 minutes). Tool stability is reduced to 53 minutes at a lower speed ja due to deterioration of heat removal from the cutting zone and at higher speeds up to 57 minutes due to an increase in the total cutting speed, leading to an increase in tool wear.

Claims (1)

The invention method of machining with a rotating tool, according to which the workpiece and the tool with 5, a heat pipe with a coolant located inside it is reported by the splicing movements around the intersecting axes and the relative feed movement that causes a hem that, in order to improve the quality and performance of the treatment, by reducing the heat tolerance in the cutting zone and leveling temperatures along the cutting edge, use a tool with a heat pipe closed in length, determine the speed of movement of the coolant in the pipe, rotate the pipe at a speed not exceeding the speed of movement of the coolant into heat rotate the pipe and the tool rotates at a speed not lower than the speed of rotation of the pipe 4 4