Fork type blade root milling cutter of turbine blade

Abstract

The invention provides a fork type blade root milling cutter of a turbine blade, which comprises a cutter shaft and a plurality of disc cutter bodies, wherein all the disc cutter bodies are assembled on the cutter shaft in parallel, each disc cutter body is in the cross-section shape of a boss structure, the outer edge and the shoulder of each disc cutter body are respectively provided with a plurality of cutter blades and cutter rests thereof which are uniformly distributed in the circumferential direction, the cutter blades are mounted on the cutter rests, the cutter rests are mounted on the cutter bodies, and each cutter rest is provided with an axial displacement adjusting mechanism. In the actual operating process of the milling cutter, the axial size of the milling cutter can be adjusted at any time, so that the machined blade root contour has small offset and small contour diameter error, and the milling cutter can be adapted to severe actual machining conditions, thereby improving the cutting and positioning accuracy, being safe and reliable, prolonging the service life of the cutter and achieving the advantages of convenient cutter changing, simple structure and convenient adjustment and operation.

Description

technical field [0001] The invention relates to the field of mechanical processing, in particular to a special milling cutter for machining the fork-shaped blade root profile of a steam turbine blade in a turbomachinery. Background technique [0002] In the processing of the fork-shaped blade root profile of steam turbine blades, disc-shaped milling cutters equipped with machine-clamped blades are generally used. Since disc-shaped milling cutters are generally large in diameter and thin in thickness, the manufacturing accuracy of the insert groove is not easy to meet the drawing requirements due to its structural limitations in processing and manufacturing. At the same time, in the actual use of milling cutters, Due to the release of the internal stress of the tool, the size of the processed product is out of tolerance, that is, the actual cutting width of the tool becomes larger, so that the error of the profile width of a group of blade root profiles is large and out of to...

AI Technical Summary

Problems solved by technology

Since disc-shaped milling cutters are generally large in diameter and thin in thickness, the manufacturing accuracy of the insert groove is not easy to meet the drawing requirements due to its structural limitations in processing and manufacturing. At the same time, in the actual use of milling cutters, Due to the release of the internal stress of the tool, the size of the processed product is out of tolerance, that is, the actual cutting width of the tool becomes larger, which makes the error of the profile width of a group of blade root profiles larger and out of tolerance, and even makes the milling cutter scrapped

Or, even if the design accuracy of the tool is guaranteed during manufacturing, due to the poor actual processing conditions, such as the large spindle runout of the processing machine tool and the bending of the tool bar, etc., it is possible that the milling cutter will reduce the cutting width during processing. Increased size leads to out-of-tolerance blade root profile

[0003] In the prior art, for the processing of the fork-shaped blade root profile of this blade, either a welded fork-shaped blade root milling cutter, an integral high-speed steel fork-shaped blade root milling cutter, or a machine-clamp replaceable fork-shaped blade root milling cutter, all Unable to solve the root size out of tolerance caused by the above reasons

Tool cutting width error and position deviation caused by on-site operation problems such as spindle runout and tool bar bending of the processing machine tool

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