JPS5910471A - Build up welding method of inside wall surface in narrow gap - Google Patents

Abstract

PURPOSE:To form easily a build up layer in a desired place with a simple operation by heating only the part near the desired part for the purpose of build-up welding on the inside wall surface in a narrow gap to melt by an electron beam welding method and melt sticking the powder of the hard material packed in the narrow gap. CONSTITUTION:Build up welding is applied in a part of the internal gap of, for example, an extrusion die 1 by the following method: The die 1 is placed on a base plate 2, and powder 3 of a hard material is packed in the internal gap preferably leaving the upper part thereof empty. The part near the inside wall surface in the internal gap of the die 1 is heated to melt only in the part to be subjected to build up welding by electron beam welding to melt stick the powder 3 existing in said part on the inside wall surface, thereby forming a build up layer 4. The unmolten powder 3 is dropped and discharged by removing the plate 2.

Description

[Detailed description of the invention] This article relates to a method of welding required materials to a wall surface.

For example, the internal gap (≦
) is often overlaid with various hard materials (3) to give it wear resistance, etc., but if the gap is narrow, welding rods and welding torches may be used. It was very difficult to charge such materials, and sufficient welding could not be achieved. Furthermore, it is often difficult to process hard, large-resistant materials such as WC and Tie, or composite materials of such hard refractories and metals or alloys into welding rods, which often imposes pressure on the welding material. There is also.

The present invention aims to eliminate the above-mentioned drawbacks and provide a method that allows easy overlay welding of a wide variety of materials within a narrow gap. After filling the gap and melting it by heating only the vicinity of the desired part of the inner wall surface of the gap to weld the hard material powder existing there, the unmelted hard material powder is discharged. This is an overlay welding method for the inner wall surface of a narrow gap.

In the present invention, the type of hard material powder used is not particularly limited, and may be a single or mixed powder of famous metals or alloys, or WC. It can be selected from a wide range of materials such as TiC, extra-hard and large-sized composite materials.

The method of the present invention will be explained in detail below with reference to the drawings.

Fig. 2 shows the case where overlay welding is applied to a part of the internal gap of the extrusion die (1).
As shown in figure (a), dice (1) are placed on a suitable base (2).
) and fill the internal gap with hard material powder (3).
In this case, if the hard material powder (3) is filled up to the height of the part to be overlay welded, it is better to leave the upper part empty for subsequent electron beam welding. Favorable for work. After filling the desired amount of hard material powder (3) in this manner, the inner wall surface of the internal gap of the die (1) is heated and melted only in the area where overlay welding is to be performed, by electron beam welding. Then, the hard material powder (3) existing in the area is welded to the inner wall surface, and a built-up layer (
4) and then unmelted hard material powder (3)
is discharged by removing the base (2).

Of course, the method of the present invention can be used not only when the gap between the workpieces passes through the top and bottom as shown in Fig. 2, but also when a narrow and deep gap is formed from one direction as shown in Fig. 3. can also be applied, and in that case, the base (2) in the case explained in FIG. 2 is unnecessary, and the other methods are the same.

As described above, according to the method of the present invention, even when the gap between a workpiece such as a die is so narrow that it cannot be overlaid by normal welding, the hard material powder of the desired composition can be placed in the gap. A build-up layer can be easily formed at a desired location by the simple operation of filling and emitting an electron beam from the upper opening, and the thickness of the build-up layer can also be easily adjusted.

In addition, in the method of the present invention, powder is used as the material for the overlay layer, so
Since it is possible to use materials that are difficult to process into welding rods through normal processing such as rolling, there is also the advantage that a wide variety of materials can be selected for the overlay layer.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional explanatory diagram showing a normal die, Figure 2 (A)
, (B), and (C) are cross-sectional explanatory views showing each step of the method of the present invention, and FIG. 3 is a diagram showing another form of the method of the present invention.
Surface explanatory diagram. In the figure, (1): Dice (3): Hard material powder (4): Overlay layer Patent applicant: Kuroki Kogyo Co., Ltd. Director Noriyoshi Jiyoshi Figure 1
Figure 2

Claims (1)

[Claims] 1. Fill the narrow gap with hard material powder, heat and melt only the area near the desired area of the inner wall surface of the double gap by electron beam welding, and weld the hard material powder existing there. , an overlay welding method for the inner wall surface of a narrow gap, which is characterized by discharging unmelted hard material powder.