JPS5836468Y2 - steel pipe welding equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a welding device for circumferential joints of large-diameter steel pipes, such as penstocks installed in power plants.

Traditionally, penstocks installed at power plants have been installed in a variety of ways, such as horizontally, slanted, or vertically, but all of them are short pipes welded on-site.

In these welding processes, the penstock pipes to be welded and connected are in a fixed state, so when performing automatic welding, the welding machine must be rotated along the inner circumferential surface of the pipe to perform welding in all positions.

For this reason, conventional welding work was carried out by attaching a guide rail to the inner circumferential surface of the penstock and rotating the welding machine along this guide rail, but this resulted in the total length of the penstock becoming longer and the material of the pipe being different. With the advent of high-strength steel, various problems have arisen in welding methods.

The present invention was made with the aim of improving these problems, and in particular provides a steel pipe welding device that is configured to be able to cope with a certain degree of diameter change and to perform highly accurate welding. be.

An embodiment of the present invention will be described below based on the drawings.

In the drawing, 1 and 2 are penstocks, and 3 is penstocks 1 and 2.
This is the welded joint part.

4 is a central shaft; 5 is an annular frame for supporting the central shaft; the annular frame 5 has a support roller 7 in contact with the inner surface of the penstock 1;
It is supported via a movable central shaft support device 6 having a movable center shaft support device 6.

The central shaft 4 is supported by an annular frame 5 via a support frame 8.

Reference numeral 9 is a rail support guide and is attached to the end surface of the annular frame 5 on the side where the welding machine is attached at an equal angle, for example, as shown in FIG.
They are arranged in the radial direction at equally divided positions.

As shown in FIG. 4, the details of the rail support I/guide 9 are such that its cross section has a dovetail groove 10 shape (FIG. 4b), and the bearings 11, 11 provided at the upper and lower edges are screwed. axis 12
is rotatably mounted, and a handle 13 is mounted on the upper end of this screw shaft.

Reference numeral 14 denotes an L-shaped guide rail support 1-, and an engaging protrusion 15 that engages with the dovetail groove 10 is provided on the outer side of one end of the guide rail support 14. A screw hole 16 is provided, and the rail support guide 9 is supported through a screw shaft 12 that is screwed into the screw hole 16, and by rotating the handle 13 of the screw shaft 12, the force idle rail support 14 is released. It is configured to be movable in the direction.

Reference numeral 17 denotes an annular guide rail, which has a circular cross section, and is attached to the opposing inner surface of the guide rail support 14 with a plurality of rails running parallel to each other.

The annular guide rail 17 can be positioned concentrically with the penstock 1 by adjusting the vertically movable support device 6 and the handle 13 of the screw shaft 12 attached to the rail support guide 9.

Further, the guide rail 17 is detachably provided so that it can be replaced when the diameter of the penstock pipes 1 and 2 to be welded changes.

18 connects the guide rail 17 to the guide rail support 1
This is a mounting bracket that is pivoted to 4.

FIG. 5 shows a schematic configuration of a traveling drive device 19 of a welding machine.

That is, the drive device 19 is a device that guides and moves the welding machine main body 20 on the guide rail 17.
Pinion 22 and gear 2 from motor 21 installed inside
Shafts 24A and 24B driven through shafts 3A and 23B are rotatably attached to the welding machine main body frame 20A, and a wheel 27 is attached to the other end of the shafts 24A and 24B with springs 26A and 26.
The welding machine main body 20 is attached by nuts 25A and 25B via B, and the side wheels 27 sandwich the power idle rail 17 from both sides, making it possible to perform welding in all positions by suspending the welding machine main body 20.

FIG. 6 shows the details of the wheel 27. The wheel 27 consists of two wheels 28A and 28B whose outer circumferential ends have an arcuate cross section. S is provided and fitted onto the drive shaft 24A, and the key 29
One wheel body 28A is fixed and the other wheel body 28B
is slidable in the axial direction.

A spring 26 is interposed between each nut 25 and the wheel body 28B, and the guide rail 17 is
It is designed to hold.

FIG. 7 shows the details of the central shaft support device 6. To explain this, 30 is a casing of a worm reducer 31, and this casing 30 is provided to protrude outward in the axial direction of the annular frame 5 for supporting the central shaft. support roller mounting member 3
It is attached to the central axis 4 side of the through hole 33 of No. 2.

34 is a worm gear 35 whose upper end is a worm reducer 31
The screw shaft 34 has a flange 34A provided below the casing 30.
A bearing 36 is provided between A and the casing 30.

The threaded portion 34B of the screw shaft 34 is screwed with a female threaded portion 37A of a support cylinder 38, which has a support roller 7 pivotally attached to its lower end and a nut member 37 fixed to its upper portion.

Therefore, by operating the worm reducer 31,
By rotating the support cylinder 38 is guided by the guide ring 39 and moves in the axial direction of the screw shaft 34, bringing all the support rollers 7 into contact with the inside of the penstock 1, and The central axis and the axis of the central axis 4 can be made to coincide.

Reference numeral 40 is a ring girder and is attached to the outer end of the arm of the central shaft 4 through a support 41 so as to be concentric with the central shaft 4.

A guide member 42 is attached to the upper part of the ring girder 40 so as to be slidable in the vertical direction, and a perfect circle holding girder 43 having the same curvature as the inner surface of the penstocks 1 and 2 is attached to the upper end of the guide member 42. is installed.

The perfect circle holding girder 43 is composed of three arc-shaped divided girders 43
A, 43 B, 43 C and one hydraulic cylinder 4
4 are connected by hinges 45 to be expandable and retractable, and the hydraulic cylinder 44 is actuated to push out the perfect circle holding girder 43 and press its outer surface against the inner surface of the penstock 2, which is the steel pipe to be welded. This makes it possible to maintain the perfect circle of the penstock 2 and to perform surface alignment with the welded portion of the penstock 1.

Next, the working procedure using the device of the present invention will be explained.

First, the device of the present invention is carried into the penstock 1 and supported within the penstock 1 by the support rollers 7 of the annular frame 5 having the central axis 4.

The welding nozzle 20 of the welding machine 20 moves on the annular guide rail 17 attached to the guide rail support 14.
B is positioned on the center line of the weld joint part 3.

Then, the screw shaft 34 is adjusted by operating the worm reducer 31 provided on the central shaft support device 6, so that the central axis of the penstock 1 and the central axis of the welding device 4 are aligned.

Furthermore, the handle 13 of the rail support guide 9 of the annular frame 5 is operated to adjust the position, and the annular guide rail 17 on the guide rail support 14 connected thereto is aligned with the inner surface of the penstock 1.

Next, after adjusting the gap between the center line of the circumferential weld joint and the welding nozzle 20B, the hydraulic cylinder 44 is operated to move the roundness holding girder 43 in contact with the inner surface of the penstock 2 as shown in FIG. The outer surface of the roundness holding girder 43 is pressed against the inner surface of the steel pipe 2 to be welded to align the welded joint portion 3.

Then, the welding machine body 20 is moved and welding is started by holding the annular guide rail 17 from both sides and driving the wheels 27 that move while being guided by the annular guide rail 17.

In this case, the two-part wheel body 28A and the lower wheel body 28 of the wheel 27
There is a gap S between B, and the wheel body 28B is pressed against the wheel body 28A side by the spring 26 interposed between it and the nut 25, so that the annular guide rail 17
It is sandwiched by 8A and 28B.

Therefore, the gap S between the two axles 27 and 27 is reduced by the buffering of the springs, and the frictional force between the annular guide rail 17 and the two axles 27 is increased, so that the welding machine main body 27 is securely
can be moved.

Note that while the welding nozzle 20B is located in the upper half, the wheels 27, 27 tend to move away from the annular guide rails 17, 17, so the frictional force with the annular guide rail 17 is maintained by the buffering force of the spring 26. The device is set in advance so that it can be pressed against the camera, so that it can be moved in a suspended state.

Thus, the welding machine body 20 moves along the annular guide rail 17, and the welding nozzle 20B performs welding in all positions while rotating and returns to the starting point.

Next, when the welding work is finished and the entire device is moved in the axial direction, the hydraulic cylinder 44 is operated to move the roundness maintaining girder.
43 and separate it from the inner surface of the penstock 2 to provide a clearance.

Then, the worm reducer 31 of the upper central shaft support device 6 is driven to separate the support roller 7 from the penstock 1 and provide the necessary rear balance to allow the support roller 7 to pass through the welded joint 3 between the penstock 1 and the penstock 2. The entire device is then moved to the next weld joint.

Note that two to three welding machine bodies 20 according to the present invention can be used simultaneously to perform welding.

In addition, the perfect circle holding girder 43 and the annular force idle rail 1
7 is used by replacing it according to the diameter of the penstocks 1 and 2.

As described above, according to the present invention, a support roller that can move in and out in the radial direction of the steel pipe is provided on the annular frame, and an annular guide rail that can be moved and adjusted in the radial direction of the steel pipe in the same manner as the support roller is provided concentrically with the annular frame. By moving the welding machine main body along the guide rail, it is possible not only to align the center axis of the steel pipe to be welded with the center axis of the welding device very easily and smoothly, but also to Since guide rails of various sizes are detachable and replaceable, the most suitable one can be selected and used depending on the diameter of the steel pipe.

In addition, the support rollers can also move along the inner surface of the steel pipe in the axial direction of the steel pipe, making it extremely easy to move the steel pipe in the axial direction within the steel pipe of the welding device. This eliminates the troublesome work of having to reassemble the guide rail when mounting and welding positions, and can be expected to significantly improve work efficiency.

In addition, by using the roundness holding girder, the steel pipe to be connected can be held concentrically with the steel pipe easily, quickly, and reliably, which has the remarkable effect of accurately and reliably aligning the welded part. can be expected.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention. Figure 1 is a front view of the right half of the steel pipe welding apparatus of the present invention, Figure 2 is a partially cutaway side view, and Figure 3 is a diagram showing a girder for maintaining a perfect circle. FIG. 4 is a partially cutaway side view of the guide rail support 1-, FIG. 4a is a view taken from section A in FIG. 4, and FIG. B sectional view, Figure 5 is a front view of the welding machine drive device, Figure 6 is a front view of the welding machine drive device.
The figure is a detailed view of the wheel in FIG. 5, and FIG. 7 is a partially cutaway sectional view of the annular frame support device. 1.2... Penstock pipe, 3... Welded joint part, 4... Central shaft, 5... Annular frame for supporting the central shaft, 6... ... Central shaft support device, 7.
...support roller, 8.41...post,
9...Rail support guide, 12...
・Screw shaft, 14...Guide rail support, 1
7... Annular guide rail, 19... Wheel drive device, 20... Welding machine main body, 27...
...Wheel, 40...Ring girder-143.
・・・・・・Perfect circle holding girder

Claims (1)

[Scope of utility model registration request] An annular frame for supporting a center shaft having a support roller configured to be movable on the inner surface of the steel pipe in the axial direction of the steel pipe and capable of moving in and out in the radial direction of the steel pipe; A central shaft installed concentrically with the axis, multiple rail support guides installed radially at equal angles to the welding machine installation end of the annular frame, and a rotatable rail support guide. a guide rail support mounted so as to be movable and adjustable in the radial direction via an axle shaft mounted on the guide rail support, an annular guide rail concentric with the central axis and removably mounted inside the guide rail support; A welding machine main body equipped with wheels that rotate while holding rails from both sides, a ring girder that is concentrically attached to the outer end of the arm of the central shaft via a support, and a ring girder that is attached to the ring girder. A hydraulic cylinder and a plurality of other arcuate members having the same curvature as the arcuate member are connected in an annular manner to the arcuate member having the same curvature as the inner surface of the steel pipe, and the connected steel pipe is expanded and contracted by the expansion and contraction action of the hydraulic cylinder. and a circular frame holding girder configured to hold the steel pipe concentrically with respect to the steel pipe, and the circular frame holding girder and the annular frame are arranged so that they can be mutually positioned in other steel pipes with the welded joint part sandwiched between them. A steel pipe welding device characterized by: