JPS61165275A - Edge welding method - Google Patents

Abstract

PURPOSE:To improve the efficiency of edge welding with good finish accuracy in build-up welding of the top end of the projecting line part of a turbine blade, etc. by forming a build-up spacing to the upper part of the projecting line by a pair of blocks facing each other and packing a deposited metal into the spacing. CONSTITUTION:The build-up spacing is formed in the upper part of the projecting line 1 by a pair of the blocks 4, 5 facing each other and a heat-resistant and wear-resistant material is build-up welded 9 to the upper part of the projecting line 1 in said space. The projecting line 1 and the deposited metal 9 are cooled by the cooling blocks and therefore the deformation of the projecting line 1 is prevented, the shape of the deposited metal is stabilized and the finishing accuracy and working efficiency are improved. The blocks 4, 5 may be cooled with water if necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an edge welding method for performing overlay welding on the upper part of a protruding part of a turbine blade or the like.

[Prior art] In turbine blades, etc., a highly wear-resistant metal is overlaid on the upper end of the blade in consideration of its wear resistance, or when the blade is worn out, the wear is replaced by repair work. I do things like weld.

The conventional edge welding method is shown in Figures 5 to 8.
There is.

In the figure, reference numeral 1 denotes a protrusion of a turbine blade or the like formed on the base body 2, and the upper end of the protrusion 1 is directly overlaid with weld metal.

[Problems to be solved by the invention] However, the wall thickness of the protrusions is sometimes as thin as 0.3n++n, and when conventional edge welding is performed, the protrusions themselves are deformed by the heat during welding, and the overlay metal (Beads) are also unstable, meandering and waving up and down.

Means for Solving Problem E 1 The present invention has been made in view of the above-mentioned circumstances, and a build-up welding space is formed on the upper part of the protrusion by a pair of opposing cooling blocks, and the weld metal is deposited in the space. It is designed to be filled.

[Function] Required build-up can be performed in one welding operation, the cooling block regulates the shape of the weld metal, and the protrusions are cooled to prevent deformation.

[Example] The present invention will be described in detail below with reference to the drawings.

A pair of cooling blocks 4.5 forming a built-up space 3 in the second part of the protrusion 1 are arranged so as to sandwich the protrusion 1, and both cooling blocks 4 and 5 are secured by a required fixture 6. Fix it. The fly wire 7 is melted by the arc 8 and filled into the build-up space 3 described above.

During the welding process C, the protrusions 1 and the weld metal 9 are cooled by the cooling block 4.5, so that deformation of the protrusions 1 is prevented and the shape of the weld metal 9 is stabilized.

In addition, if the amount of overlay is large, multi-layer overlay may be used as shown in FIG.

Furthermore, in order to eliminate poor fusion between the protrusion 1 and the weld metal 9, the bottom of the build-up space 3 should be shaped as shown in FIG. 4.

That is, the groove width W of the build-up space 3 is made slightly larger than the wall thickness t of the protrusion 1, and the upper end of the protrusion 1 protrudes into the build-up space 3, and the lower end of the build-up space 3 is rounded or tapered. The groove width is gradually decreased to t.

Here, the reason why the groove width W of the build-up space 3 is made larger than the wall thickness tJ of the protrusion 1 is due to the cutting allowance in post-processing.

Note that the cooling block described in (g) may be water-cooled, or may be a metal block with good thermal conductivity when the welding heat input is small.

Further, if the cooling block has sufficient weight, no special fixtures are required.

"Effects of the Invention" As described above, according to the present invention, it is possible to perform edge welding with high accuracy and efficiency.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a side view of an edge weld in which the present invention is implemented, FIG. 3 is a front sectional view, and FIG. 4 is an enlarged view of the bottom of the overlay space. FIG. 5 is a perspective view of the edge welding area, FIG. 6 is a side view of the edge weld when the conventional method is carried out, FIG. 7 is a plan view, and FIG. 8 is a front sectional view. 1 is a protrusion, 2 is a base body, 3 is a build-up space, 4 and 5 are cooling blocks, 6 is a fixture, 7 is a filler wire, 8 is an arc, 9
indicates weld metal.

Claims (1)

[Claims] 1) An edge welding method characterized in that a build-up space is formed on the upper part of the protrusion by a pair of opposing cooling blocks, and the space is filled with weld metal.