SU1227341A1 - Method of working by cutting - Google Patents

Description

one

The invention relates to metal cutting and can be used in the processing of hard-to-machine materials, such as heat-resistant steels and alloys, with preferential tool wear on the back surface.

The purpose of the invention is to increase the durability of the cutting tool, preferably wearing on the back surface.

Figure 1 shows a lathe tool with mechanical fastening carbide plate and a wedge-shaped lining; figure 2 - the original geometry of the cutting wedge; Fig. 3 shows the geometry of the cutting wedge after reaching the specified limit wear and subsequent rotation in the direction of decreasing the rear angle; Fig. 4 shows the same after processing and turning in the direction of increasing the rear angle; Fig. 3 is a graph of the dependence of the cutting forces P., - and RC on the turning time with periodic turning of the tool; Fig. 6 is a graph of the cutter's wear on the back surface versus turning time.

The method is carried out as follows.

In the initial period, the treatment, predominantly of heat-resistant steels and alloys, is carried out with the tool’s optimum geometrical parameters for durability. Upon reaching the established

experiments taking into account the statistical time, - throwing a critical amount of wear

back surface, i.e. after which the wear rate rises sharply and wear becomes catastrophic, the tool is turned (around the top), increasing or decreasing the back angle.

In this position, machining is continued, and in the case of a reduction in the back angle, machining is continued. lead in the mode of steady growth. After reaching a newly formed chamfer of critical size, the tool is re-rotated in the opposite direction2273412

previous anterior, lean turn. These techniques are performed multiple times.

To simplify the process, the critical wear points are determined by the 5 treatment time, as determined from preliminary tests.

The cutter for the implementation of the proposed method contains a holder

shift

a cutting blade-2 mounted at an incision angle J g, p and having a main clearance angle, a rotary wedge-shaped lining 3 and a unit for fixing the cutting blade 2 and the lining 3 in the form of a screw 4 with a screw 5.

Example. A holder 1 with a plate 2 of solid 4/9 VK8 alloy is used. The material to be processed is a heat-resistant nickel-based alloy, Ey 787, a grade of hard alloy VK8. The modes of turning: cutting speed V 20 m / min, feed S 0.23 mm / rev, cutting depth t, 0 mm, coolant - emulsion No. 73.

The turning is done on an IK62 turning-screw machine. Initially, processing is carried out with the geometrical parameters of the cutter optimal for the given conditions: front

OO

angle of 10; rear angle oi 10; chamfer angle UD,. After reaching critical wear level,. determined by the width of the contact of the back surface of the cutting plate with the workpiece, equal to 0.4 mm, rotate the plate 2, for example, in the direction of decreasing the rear angle of by the angle Do; by turning the wedge-shaped lining 3 around its vertical axis. Re

bumping the top as it rises.

Then, cutting again is carried out until a contact width h of 0.4 m is formed, after which plate 2 is turned in

upside down angle

angle uotf, 2 30 and continue cutting until the loss of the plate 2 health.

The application of the proposed method improves the durability of the cutting tool when machining hard-to-use materials such as heat-resistant steels and alloys.

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Compiled by V.Zolotoe Editor E.Kopcha Tehred V.Kadar Proofreader M.Sharosh

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VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab ,, d.4 / 5

Production and printing company, Uzhgorod, Projecto st., 4

Claims (1)

METHOD FOR WORKING WITH A CUTTING method, including alternately decreasing and increasing the rear corner of the cutting tool by turning it around the apex, characterized in that, in order to increase the resistance of the cutting tool, the next turn is carried out to achieve critical wear of the cutting edge, and when reducing the rear angle, the processing in the mode of steady growth.