RU2574564C2 - Method of final milling of curvilinear surface of blades body of gas turbine engines - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: method includes use of a spherical cutter having and teeth with blunted cutting edges on the jumper with overlapping of the axis of rotation of the cutter, that is installed with axis of rotation at right angle in each point of contact with machined surface. The cutter is provided with eccentric rotation by means of its securing in the eccentric-bushing, installed in spindle of the milling machine, and compaction of the surface layer of the machined surface is performed by the blunted cutting edges of the cutter, and surface layer is flattened by creation of the flat area ensuring overlapping of the ridges and depressions created on the machined surface due to the cutter movement.

EFFECT: reduced surface roughness of the blade body, increased quality.

4 dwg

Description

The invention relates to mechanical engineering and can be used in the operations of fine milling of the curved surface of the pen blades of gas turbine engines with an end spherical mill. The invention can be used in engineering, aviation, shipbuilding, space and other industries.

There is a method of fair milling of curved surfaces, in which the axis of the cutter at the point of contact deviates from the normal to the machined surface (See, for example, SU AS No. 1060349, CL B23C 3/18, 1983).

The disadvantage of this method is the discontinuity of the cutting process, the presence of scallops and troughs from the movement of the cutter.

There is also a method of fine milling with an end spherical mill with sharp cutting edges of a curved surface, in which the axis of the end spherical mill is set normal to the point of contact with the surface to be machined (See, for example, SU a.s. No. 331620, class B23C 3/18 , 1985).

The disadvantage of this method of milling is the high roughness of the machined curved surface, located under the axis of rotation of the cutter, where the cutting speed is minimal.

The closest technical solution to the invention in terms of technical nature and the achieved result is a method of fine milling a curved surface of a feather of a blade of a gas turbine engine with an end spherical milling cutter containing end teeth, including its installation with the axis of rotation normal to each contact point with the surface to be machined (See, for example, RU patent No. 2351441 C1, CL B23C 3/18, 04/10/2009). The specified technical solution is selected by the applicant as a prototype.

The disadvantage of this method of milling is the high roughness of the machined curved surface, due to scallops and troughs from the movement of the cutter.

The technical result of the proposed method is the finish milling of curved surfaces with an end spherical mill.

The specified technical result is achieved by the fact that in the method of fine milling the curved surface of the feather of the blades of gas turbine engines with a spherical end mill containing end teeth, including its installation with the axis of rotation along the normal to each contact point with the machined surface, use a mill with end teeth having blunt teeth the cutting edges on the jumper with their overlapping axis of rotation of the cutter, while the cutter communicate an eccentric rotation by fixing it in the sleeve-e to the center, installed in the spindle of the milling machine, and the surface layer of the workpiece is densified with the blunt cutting edges of the cutter and the surface layer is smoothed out by creating a flat platform that ensures that the combs and depressions formed on the treated surface overlap from the movement of the cutter.

The essence of the proposed method is illustrated by drawings, which depict:

in FIG. 1 is a general view of the machined curved surface of a feather blade;

in FIG. 2 is an end view of the end mill;

in FIG. 3 - edge option with blunting angle;

in FIG. 4 - same with blunting radius.

The method of fine milling the curved surface of the feather of the blades with an end spherical mill is implemented by the following device containing a spherical end mill 1, fixed in the eccentric sleeve 2, which is in turn installed in the spindle 3 of the milling machine. The axis 4 of the cutter 1 is spaced from the axis 5 of the spindle 3 by the amount of eccentricity - "e". The jumper 6 of the cutter 1 has a blunting of the cutting edges.

The proposed method of fine milling the curved surface of the feather blades of the end spherical mill is as follows. The milling cutter 1 is rotated around its own axis 4. The blunt cutting edges 8 of the jumper 6, when the milling cutter 1 rotates in the eccentric bushing 2, compacts the surface layer 7 of the processed material, and the rotation of the milling cutter 1 with an eccentricity “e” around the axis 5 of the spindle 3 creates a flat area -S, ensuring the overlapping formed on the surface of the scallops and troughs from the movement of the cutter 1, smoothing the surface layer of the processed material.

Using the proposed method will improve the quality of the machined curved surfaces of the feather blades of the GTE by reducing the surface roughness of the machined parts.

Claims (1)

The method of fine milling the curved surface of the feather of the blades of gas turbine engines with a spherical end mill containing end teeth, including its installation with the location of the axis of rotation along the normal at each point of contact with the machined surface, characterized in that they use a mill with end teeth having blunt cutting edges on the jumper with overlapping of the axis of rotation of the cutter, with this cutter, an eccentric rotation is reported by fixing it in the eccentric bushing installed in the spindle le of the milling machine, and the surface layer of the treated surface is densified with the blunt cutting edges of the cutter and the surface layer is smoothed out by creating a flat platform that ensures that the combs and depressions formed on the treated surface overlap from the movement of the cutter.

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