JPS6219944B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a welding device that enables overlay welding in narrow and deep holes.

In a narrow and deep hole, for example, when applying stellite overlay to provide wear resistance to the valve seat surface of the turbine main stop valve, the overlay part is manufactured separately to take into consideration the shape. It is often fixed afterwards. As shown in Fig. 1, the valve seat of this turbine main stop valve has a hole 01 for introducing a welding torch that has a small diameter of 100 mmφ, and a welded portion 02 that is located at a position of about 1000 mm.
Manual welding is impossible because the welding rod 03 cannot reach the welding location 02 and the welding area is not visible, and current welding equipment is too large to perform welding.

Therefore, as shown in FIG.
4 and the valve seat portion 05 are manufactured separately and then fixed by welding. According to this divisional manufacturing, the valve seat 05 and nozzle holder 06 are manufactured separately, while the insertion part of the main blocking valve body 04 is processed, and then the valve seat seat surface 07 is overlaid welded, and then this overlay welded part is is machined, and then the valve seat 0 described above is machined.
5 and the nozzle stub 06 must be welded (molten metal 08) to the main stop valve body 04. After that, radiographic inspection is performed and local annealing (the welded part) is performed. Therefore, the manufacturing process is complicated and requires a lot of man-hours.

An object of the present invention is to provide an automatic overlay welding device capable of welding narrow and deep holes.

The structure of the present invention to achieve such an object is that a nozzle whose tip is bent so as to face the part to be welded and guides the welding wire to the part to be welded is attached to the lower end of the rotating main shaft in the welding head, and A frame carrying a wire drum and a wire feeding motor is placed on the upper end of the rotating main shaft and rotated together with the nozzle, while the welding wire is passed through the rotating main shaft and introduced into the nozzle, A fine adjustment slider is used to finely move the welding head in three mutually orthogonal directions (up, down, left, right, front and back), and it is supported by the upper and lower sliders, and the vertical slider can be raised and lowered by a carriage on a support that is installed along the object to be welded. It is characterized by being attached to.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be explained in detail below based on an embodiment shown in the drawings.

A vertical slider 4 that moves vertically above a carriage 3 that runs horizontally on a rail 2 that spans a support 1 is fine-adjusted in three orthogonal directions: up and down, left and right, and front and back. The casing 5, which forms the basis of the welding head, is attached via the respective fine adjustment mechanisms provided.

The welding head A consists of a wire supply system, a rotating mechanism (rotating main shaft 6), and a nozzle 8 whose tip is bent so as to face the welding part and guides the welding wire 7 to the welding part. The wire feeding system includes a wire drum 9 around which a wire (filler metal) 7 is wound, and a wire feeding motor 1 that feeds out the wire 7.
0 and a frame 11 that supports them, and is mounted on a rotating main shaft (hereinafter referred to as main shaft) 6 that is rotatably supported in a casing 5 via a thrust bearing 12 and a radial bearing 13. The wire supply system is provided with a frame 11 fixed to the main shaft 6 so as to rotate together so as not to twist the wire 7. Further, at the lower end of the main shaft 6, a substantially U-shaped frame 14 supporting a nozzle 8 for guiding the wire 7 to the welding part is provided.
is fixed. The frame 14 has a nozzle 8
A threaded rod 15 for lateral movement and a guide rod 16 are rotatably installed. Therefore, threaded rod 1
5, the nozzle 8 is moved in the horizontal direction while preventing the substantially L-shaped nozzle support piece 17 from rotating. The wire 7 fed from the wire feeding system is introduced into the nozzle 8 through a wire guide flexible tube 18 passing through the main shaft 6. The main shaft 6 is rotated by a worm gear 20 that meshes with a worm wheel 19 fixed to the main shaft 6, and a motor 21 for rotation outside the casing 5.
It can be obtained by turning. Further, power is supplied to the wire 7 from a power supply slip ring 22 which is insulated from other elements and rotates together with the main shaft 6.

A flux container 24 like a funnel is connected to a flux supply tube 23 in the middle of the nozzle 8.
is fixed. The flux container 24 temporarily stores the flux B to be supplied to the welding part for stable supply, and receives the flux B from a flux container 25 fixed to the casing 5.

The welding head consists of a casing 5 that houses a nozzle 8, a wire supply system, and a main shaft 6 that rotates them.The welding head has a fine vertical feed slider 27 equipped with a vertical feed screw shaft 26, and a horizontal feed screw shaft 28 perpendicular to the slider 27. It is movable up and down, left and right, and front and back by a slider 29 for minute left and right feed and an arm 30 for minute back and forth feed that supports these. The arm 30 for minute forward and backward feeding
is arbitrarily moved out and out of the vertical slider 4 by the engagement of the rack 31 and pinion 32.

The vertical slider 4 moves up and down along a guide (not shown) on the carriage 3 by rotation of the feed screw rod. This feed screw rod is rotated by a vertical drive motor 34 via a bevel gear 33. still,
A scale plate 35 for measuring the amount of vertical feed of the nozzle 8 is attached to the carriage 3.

The carriage 3 clamps the rail 2 supported by the support 1 with clamping rollers 36, and is movable by rolling rollers 37, and is held on the rail 2 so that it can run on the same plane. has been done.
The carriage 3 is pulled horizontally by the rotation of a chain 39 stretched between a drive sprocket (not shown) and a driven sprocket 38.

Since the apparatus of the present invention is constructed as described above, it is operated as follows.

First, stand 40 installed near pillar 1
The workpiece 41 to be welded is placed thereon, and then the carriage 3 is moved by the operation of the lateral movement chain 39, and the welding head A is installed directly above the valve hole 01, which is the part to be welded. Of course, when moving the carriage 3, it is necessary to raise the vertical slider 4 to its upper limit so that the tip of the nozzle 8 does not collide with the workpiece 41. Next, the welding head A is lowered by the fine vertical feed slider 27, and the tip of the nozzle 8 is set on the upper surface of the workpiece 41 to be welded. Then, the head moving pinion 32
is rotated to move the minute forward/backward feeding arm 30 in the forward/backward direction so that the center of the nozzle 8 and the center of the hole 01 of the workpiece 41 in the forward/backward direction approximately coincide with each other. Further, while driving the rotation motor 21 to rotate the nozzle 8, the fine vertical feed slider 27 and the fine left/right feed slider 29 are finely adjusted to rotate the nozzle 8.
, or the center of rotation, and the center of the part to be welded. After alignment, use the vertical slider 4 to move the nozzle 8, that is, the welding head A, while watching the scale 35.
The entire body is lowered by a predetermined amount. After the nozzle setting is completed, submerged arc welding is started while supplying flux B from the flux containers 24 and 25 to the welding area.

First, weld a layer. During welding, as shown in Figure 7a, welding is stopped once at a position where the nozzle 8 is turned 3/4 of a turn (0° to 270°), the nozzle 8 is raised, the slag is removed, and the nozzle 8 is turned again. After lowering and resetting, the second layer welding is started. The second layer weld is performed by rotating 3/4 of a turn from the end point of the first layer welding toward the bottom weld (see Figure 7b). After the second layer welding is completed, the slag is removed by the same operation as described above, and then the third layer welding and the fourth layer welding are performed. Since the welding start point is shifted by 90 degrees for each layer and circumferential welding is performed in 3/4 turns, after the completion of 4-layer welding, the same build-up as if complete circumferential welding is formed. If the build-up surface is inclined like an inverted cone, the center of rotation of the nozzle 8 is shifted by using the micro vertical feed slider 27 and the lateral movement threaded rod 15 (FIGS. 7a to 7d). In this case, the nozzle tip does not need to be replaced because it is a fine adjustment device for the nozzle. Alternatively, as shown in FIGS. 6a to 6c, the hole 01 into which the nozzle 8 is inserted is small and the main stop valve body 04 is
If it is difficult to move the nozzle 8 laterally due to the tendency of the nozzle 8 to come into contact with other parts, causing an accident such as shooting, nozzles 8' may be added.

As described above, according to the present invention, circumferential build-up welding in a narrow and deep hole is possible by rotating and finely adjusting the nozzle that guides the wire. In addition, instead of rotating the nozzle 360 degrees to complete welding, welding is stopped at 270 degrees (3/4), slag is removed, and welding is performed again at 270 degrees, which eliminates defects caused by slag entrainment. It can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a central longitudinal sectional view showing the main stop valve of the turbine, Fig. 2 is an enlarged sectional view of the valve seat portion, and Fig. 3A is a welding process that can be carried out by the automatic overlay welding device of the present invention. Fig. 3B is an enlarged sectional view of the valve seat portion, and Fig. 4 is a working diagram of hand welding overlay welding on the valve seat of the main stoppage valve. Fifth
The figure is a working diagram showing the state of welding work by the automatic overlay welding apparatus of the present invention, FIG. 6 is an explanatory view showing the state of the nozzle tip, FIGS. FIG. 9 is a side view of the welding apparatus, FIG. 9 is a front view thereof, and FIG. 10 is an enlarged front view of only the welding head portion. In the drawing, 1 is a column, 2 is a rail, 3 is a carriage, 4 is a vertical slider, 5 is a casing, and 6
is a rotating main shaft, 7 is a wire, 8 is a nozzle, 9 is a wire drum, 10 is a feeding motor, 11 is a frame,
27 is a slider for minute vertical feed, 29 is a slider for minute left/right feed, 30 is an arm for minute back and forth feed,
41 is an object to be welded, A is a welding head, and B is a flux.

Claims (1)

[Claims] 1. A nozzle that is bent so that its tip faces the part to be welded and guides the welding wire to the part to be welded is attached to the lower end of the rotating main shaft in the welding head, and a wire drum and wire feed are attached to the upper end of the rotating main shaft. A frame on which the motor is mounted is mounted and rotated together with the nozzle, while the welding wire is passed through the main rotational shaft and introduced into the nozzle, and the welding head is arranged in three orthogonal directions: top, bottom, left, right, front and back. A small-diameter deep welding device characterized in that a fine-adjustment slider for fine-adjustment movement in the direction is interposed and supported by the upper and lower sliders, and the upper and lower sliders are mounted so as to be movable up and down on a carriage on a support installed along the workpiece to be welded. Automatic overlay welding equipment for holes.