JPS61140377A - Welding equipment - Google Patents

Abstract

PURPOSE:To reduce the cost in mending by providing an arm spirally winding on a welding object and a guiding sheath body and by moving the arm in the right angles direction with the shaft of the object and by moving the sheath body in the axial direction of the object with interlocking to the movement of the arm. CONSTITUTION:A welding equipment 23 is fixed to the fixed jig which is fitted to an object 22a at the narrow gaps of adjoining panel,etc. A sliding lever 43 is driven vertically via a driving motor 46, worm gear, 47, pinion 45, etc. and the freely bending arm 49 of the lower end is moved in the right angles direction with respect to the object 22a. An arm 49 is spirally wound on the object 22a and the sheath body 63 is moved with interlocking in the axial direction. A TIG welding torch 57 is arranged on the arm 49, performing the peripheral welding and mend of the object 22 in the narrow space. Due to the cut place for amendment being able to be minimized the cost in mending is widely reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application> The present invention relates to a welding device, and is suitable for use in local repair of closely arranged rod-like objects such as pipes and rods.

<Prior art> In a structure where a large number of tubes or rods such as boiler superheaters, reheat cables, heat exchange equipment, reinforcing bars, etc. are closely arranged, if the tubes or rods are locally damaged, it is necessary to remove the damage. Needs repair. This conventional repair work will be explained below using the case of a boiler superheater panel as an example.

Fig. 6 is a schematic perspective view of a boiler superheater. In Fig. 6, 11 is a superheater panel constructed by arranging a plurality of tubes in a plate shape, and one superheater is arranged at a narrow pitch. It consists of hundreds of superheater panels 11 arranged in an array.

12.13.14 is a hanging pipe, hanging pipe 12.1
3.14 is mechanically fixed to a large number of tubes constituting one superheater panel 11 by means such as welding, and maintains the shape of the superheater panel 11 in a plate shape and also serves as a ceiling part of the boiler. The superheater panel 11 is supported by being fixed to the superheater panel 11. 15 is an inlet header which is a cylindrical pressure vessel, and 16 is an outlet header which is also a cylindrical pressure vessel, and the ends of the tubes forming the superheater panel 11 are connected to each other.

Thus, steam supplied to the inlet header 15 from a piping system (not shown) is distributed to each tube of the superheater panel 11,
Outlet header 16 after passing through each tube to absorb heat
It is used for driving turbines and steam engines, heating devices, etc.

In such a superheater, the tubes used in the superheater panel 11 are subject to damage due to material aging, corrosion, etc. while being used for a long period of time. In this case, it is necessary to locally cut out the damaged part of the tube and replace it with a new tube, but the superheater has tubes arranged closely together to increase thermal efficiency (for example, panel 1
The tube spacing within the tube group is about 30ffI111, and the spacing between the panels 11 is about 60IIWl), so if damage occurs in the center of the tube group, the operator cannot approach it. Therefore, in the past, the superheater panel lla containing the damaged tube was hung from its suspension member 12a113a.

The superheater panel lla is separated from the entire superheater by cutting all the dozens of connections between the tube 14a and the tube headers 15 and 16, and the superheater panel lla is pulled up using a winch (not shown) to remove the damaged tube. Repairs and replacements were being carried out.

In other words, in the past, when a shrine or zelkova that had been arranged in secret was locally damaged and the worker was unable to approach the damaged area, the separable part containing the damaged area was separated from the whole. The damaged areas were repaired.

<Problems to be solved by the invention> Therefore, it is necessary to cut a healthy part that is not directly related to the damaged part, or to restore the cut part again after the repair is completed, which leads to poor work efficiency and high costs. However, because the process involves cutting and restoring originally healthy parts, there is a problem in that quality and reliability are significantly compromised.

Means for Solving the Problems> The present invention solves the above-mentioned conventional problems,
To provide a welding device that can be inserted into a narrow space and perform circumferential welding of rod-like objects such as pipes and rods by remote control, thereby making it possible to perform circumferential welding of rod-like objects such as pipes and rods, which can be used to perform work located in the center of a group of densely packed pipes in a boiler superheater. The purpose of this technology is to enable welding repair of damaged areas that cannot be accessed by people without cutting healthy areas.

To achieve this object, the welding device according to the present invention has a structure in which a plurality of joint bodies are pivotally connected to each other so as to be bendable, and each joint body is biased to rotate in one direction. an arm that spirally wraps around an object to be welded, a welding torch attached to the tip of the arm, a sheath body that guides the arm to the object to be welded, and an arm that is inclined at a spiral lead angle θ. a drive mechanism that moves the sheath body toward the welding target at a speed V in a direction perpendicular to the longitudinal axis of the welding target while the arm is moving; It is characterized by comprising a drive mechanism that moves the spiral at a speed V of Vtaaθ in the advancing direction of the spiral.

Function When the arm is guided by the sheath body and sent out towards the object to be welded, the arm wraps around the object to be welded in a spiral from its tip. Since the feeding direction of the arm is perpendicular to the longitudinal axis of the object to be welded, the tip of the arm does not move in the longitudinal direction of the object to be welded. The welding torch rotates around the outer periphery of the object to be welded in a plane perpendicular to its longitudinal axis, thereby performing circumferential welding of the object.

Example of implementation An embodiment of the present invention will be described in detail below with reference to the drawings.

1 to 5 show an embodiment of the present invention, in which FIG. 1 is a vertical sectional view of a welding device according to an embodiment of the present invention, FIG. 2 is a front view showing a schematic configuration thereof, and FIG. The figure is a perspective view showing an example of a state in which a welding device according to an embodiment of the present invention is attached to a fixing jig, and FIG. 4 is a perspective view showing a state in which the fixing jig is fixed to a tube of a boiler superheater. FIG. 5 is a schematic overall perspective view showing the state in which the present apparatus is applied to tube welding work of a boiler superheater.

As shown in FIG. 5, a pair of fixing jigs 21 are inserted into the gap between the adjacent superheated panels 11, and
22a, and a welding device 23 is attached and fixed to the refixing jig 21, respectively.

First, the fixing jig 21 fixes the welding device 23 in a required position.
The configuration will be explained with reference to FIG. In FIG. 4, 22a is a tube to be welded, 22b is a tube in the same panel as the tube to be welded 22a, and 22C is a tube in a panel adjacent to the panel containing the tube to be welded 22a. The fixing jig 21 has a U-shaped main body frame 24, and clamps 25a and 25b for gripping the tube are attached to both end side walls of the main body frame 24, respectively. One clamp 25a is attached to one side wall of the main body frame 24 with a back and forth moving mechanism 2.
The other clamp 25b is attached to the bracket 27a, which is attached via a horizontal movement mechanism 28, to the bracket 27a, which is attached to the bracket 27a via a horizontal movement mechanism 28.
The vertical movement mechanism 29 is attached to the bracket 27b, which is attached via the vertical movement mechanism 29. Flexible shafts 30 a, 30 b 1 for longitudinal driving, a flexible shaft 31 for horizontal movement, and a flexible shaft 32 for vertical movement are connected to these longitudinal movement mechanisms 26 a, 26 b, lateral movement mechanism 28, and vertical movement mechanism 29, respectively. , those flexible shafts 30a, 30b, 31
．． 32 drives each moving mechanism 26m, 26b.

28 and 29 are driven.

Furthermore, fluid pressure cylinders 33a and 33b are attached to the clamps 25a125b to open and close them.

Further, projecting plates 34a are provided on both side walls of the main body frame 24, respectively.
, 34b are attached so as to be movable in the front and back direction, and a flexible shaft 35 for driving the overhang plate is connected thereto.
The overhanging plate 34a134b is driven by a and 35b. Further, guide bars 36a and 36b of the welding device 23 extending in the vertical direction are fixed to both side walls of the main body frame 24, and stoppers 37a and 37b are attached to the bases thereof.

Next, the configuration of the welding device 23 will be explained with reference to FIGS. 1 to 3. As shown in FIG. 3, the casing of the welding device 23 consists of a base plate 38 and a cover 39, and a holding plate 40, which is spanned over the guide bars 36a and 36b of the aforementioned fixing jig 21, is fixed to the base plate 38. The guide rollers 41a and 41b attached to both ends of the holding plate 40 removably engage the guide bars 36 and 36b, so that the welding device 23 is slidably attached along the guide bars 36a and 36b. It's about to get hit.

Further, as shown in FIGS. 1 and 2, a pair of guide plates 42 are fixed to the base plate 38, and a slide rod 43 is supported thereon so as to be slidable in the vertical direction in the drawings. A rack 44 is fixed to the slide rod 43 in the vertical direction, and a pinion 45 is engaged with the rack 44, and the pinion 45 is rotationally driven by a motor 46 fixed to a base plate 38 via a worm gear 47 and a housing gear 48. As a result, the slide rod 43 is driven up and down.

A bendable arm 49 extending downward from the casing is connected to the lower part of the slide rod 43. The arm 49 is made up of a number of joint bodies 50 that are pivotally connected to each other with pins 51.
The axial direction of the bottle 51 is perpendicular to the direction of movement of the slide rod 43, and the joint bodies 50 are connected to each other at a predetermined angle θ with respect to the direction of movement of the slide rod 43, as shown in FIG. ing. A torch holder 52 is attached to a joint body 50 at the tip of the arm 49.
One end of a tension cable 54 is fixed to 2 by a fixing metal fitting 53. The tension cable 54 extends along each joint body 50 and is guided into the casing, and the other end is connected to a tension spring 56 fixed to a spring fixing base 55 fixed to the base plate 38 and the cover 39. . Therefore, each joint body 50 is biased to rotate in one direction by the tension cable 54 which is tensioned by the tension spring 56, so that in the free state, the arm 49 is perpendicular to the direction of movement of the slide rod 43. It is bent spirally around the axis at a lead angle θ.

Further, a TIG welding torch 57 and a builer wire tip holder 58 are fixed to the torch holder 52, and
A tungsten electrode 59 and a filler wire 60 attached thereto are aimed at predetermined welding positions. In addition, a cable hose 61 and a conduit cable 6 are provided for supplying electric power and inert gas to the TIG'm contact torch 57 and the builer wire tip holder 58, respectively.
2 are connected, the cable hose 61 and the conduit cable 62 are guided into the casing along the arm 49,
It exits from the top and is connected to a required device (not shown).

On the other hand, a sheath body 63 is provided at the lower part of the casing to house the arm 49 therein and bridge the arm 49 from the casing to the target tube 22m. The sheath body 63 is the slide rod 4
The sheath body 63 is tilted by the same angle θ as the arm 49 with respect to the moving direction of the sheath body 63, and the protrusion 63m formed on the upper part of the sheath body 63 is attached to the base plate 3B of the casing and the cover 39 so that the slide rod 43
It is attached to the substrate 38 and the cover 39 so as to be slidable in the left and right directions by being slidably fitted into a groove formed in the right and left directions perpendicular to the moving direction of the board (in the direction perpendicular to the paper surface in FIG. 1). It is being A receiving threaded portion 63b is formed in the sheath body 63, and a feed screw 64 pivotally supported by the casing in the left-right direction is screwed into the receiving threaded portion 63b. The feed screw 64 is connected to the motor 4 that drives the slide rod 43 mentioned above.
6 through a worm gear 47, a connecting rod 65, and a bevel gear 66.
3 moves in the left and right direction. That is,
The slide rod 43 and the sheath body 63 are driven by the same motor 46. Here, as shown in FIG. 2, the moving speed of the slide rod 43 is v1 and the moving speed of the sheath body 63 is v1.
9. The gear ratios are selected so that /7=-θ, where θ is the inclination angle of the sheath body 63 with respect to the moving direction of the slide rod 43.

Next, the operation of this device will be explained. First, the fixing jig 21 is placed at the position of the tube 22a to be welded on the superheater panel 11.
to be fixed. For this, the clamp 2 of the fixing jig 21 must be
5a, 25b and the overhanging plates 34a, 34b are respectively set back inward, and the fixing jig 21 is inserted between the adjacent superheater panels 110 to clamp the clamps 25a, 25.
b9! Directly face the tube 2h to be welded. Subsequently, when the flexible shafts 35a and 35b for driving the overhang plates are operated to protrude the overhang plates 34a and 34b, the main body frame 24
The fixing jig 21 is fixed between the superheater panels 11 by pressing the tubes 22b and 22c with the overhanging plates 34m and 34b, respectively. Next, the clamp 2 is moved by the front and rear driving flexible shafts 30a and 30b.
5a, 25b are advanced, and the hydraulic cylinders 33a, 33
When b is activated, the clamps 25a and 25b grip the tube to be welded 22a, so the tube to be welded 22a is fixed to the fixing jig 21.

Next, the guide rollers 41a and 41b of the welding device 23 are fitted to the guide bars 36a and 36b of the fixture 21 fixed between the superheater panels 11, respectively.
The welding device 23 is lowered along lines a and 36b and inserted between the superheater panels 11. At this time, by positioning the slide rod 43 of the welding device 23 upward so that the arm 49 is housed in the sheath body 63 and folded, the arm 49, torch holder 52, TIG welding torch 57, etc. can be connected to the superheater. Panel 11
Smooth insertion is possible without interfering with the The welding device 23 is fixed to the fixing jig 21 by coming into contact with the stoppers 37a and 37b and stopping.
The tip of the sheath body 63 of No. 3 is placed over the tube 22m to be welded.

When the motor 46 is started in this state, the slide rod 43
is lowered, and the arm 49 is sent out downward (in a direction perpendicular to the axial direction of the tube 22a to be welded) through the inside of the sheath body 63. The arm 49 is held in a straight line by the sheath body 63 until it leaves the sheath body 63, but as described above, the joint body 50 is always moved around the pin 51 by the tension cable 54.
Since it is urged to rotate sideways, when the joint body 50 of the arm 49 comes out from the sheath body 63, the joint body 5o rotates until it comes into contact with the surface of the tube 22a to be welded. In this way, as the joint body 50 is sent out from the sheath body 63, it comes into contact with the surface of the welding target tube 22m, and as a result, the arm 49 wraps around the welding target tube 22m (so that the tip thereof Together with the attached torch holding plate 52, the TIG welding torch 57 and the filament wire tip holder 58 rotate along the surface of the tube to be welded 22a.At this time, the arm 49 is tilted by θ with respect to the moving direction of the slide rod 43. Therefore, the arm 49 is the tube 22 to be welded.
It is possible to prevent the adjacent arms 49 from interfering with each other even when they are wound in a helical manner with a lead angle θ around m, and even if they are wrapped around one turn for more than − circumference. That is, as shown in FIG. 2, the length of the arm 49 along the axial direction of the tube 22a to be welded is Wl, that of the sheath body 63 is W2, and the radius of the tube 22a to be welded is R.
If 2πRmθ)W1+W2-W1=W1+W2 is satisfied, the arms 49 can move toward the tube 2 to be welded without interfering with each other.
It can be wrapped around 2a multiple times. Note that when the joint body 50 is wound around, it becomes a polygon, but in the above formula, this is made into a circle, and the thickness of the joint body 50 is ignored.

On the other hand, when the motor 46 is started, the sheath body 63 moves in synchronization with the lowering of the slide rod 43 in a direction perpendicular to the moving direction of the slide rod 43, that is, in a direction along the axial direction of the tube to be welded 22a. Here, since the moving speed v1 of the slide rod 43, the moving speed v1 of the sheath body 63, and the inclination angle θ of the arm 49 and the sheath body 63 are /7=-0 as described above, the arm 49 is inside the sheath body 63. can be moved smoothly.

In addition, in FIG. 2, the state of the slide rod 43 and the arm 49 when they start descending is indicated by a dashed line, and the state of the arm 49 when it is assumed that the arm 49 does not wrap around the tube 22a to be welded after descending is indicated by a broken line. However, as shown in Figure 2, the arm 4
9 is not wrapped around the tube 2 to be welded, the movement trajectory of the TIG welding torch 57 attached to the tip of the arm 49 is parallel to the movement direction of the slide rod 43, that is,
It is perpendicular to the 2a axis direction. Furthermore, each joint body 5 of the arm 49
0 is perpendicular to the moving direction of the slide rod 43, that is, parallel to the axial direction of the tube to be welded 22a,
Therefore, the arm 49 is sent out and the tube 22J to be welded is
TIG attached to the tip when wrapping around L
The welding torch 57 rotates around the outer periphery of the tube 22a to be welded in a plane perpendicular to its axial direction. Therefore, by starting the motor 46 and operating the TIG welding torch 57, circumferential welding of the welding target tube 22m is accomplished.

In the above-described embodiment, the arm 49 is biased to bend by the tension cable 54, but in addition, for example, the joint body 50
It is also possible to flex the arm 49 by attaching a spring to each pivot portion to urge the joint body 50 to rotate in one direction. In addition, although the above description describes an example in which the present invention is applied to a boiler heat exchanger and a heater, the present invention can also be applied to circumferential welding of reheating racks, heat exchangers, reinforcing bars, and other rod-like objects. It is possible.

<Effects of the Invention> As described above in detail with reference to one embodiment, according to the present invention, the arm is moved to the object to be welded in an extended state, and the arm is spirally wrapped around the object to be welded. As a result, circumferential welding of the object to be welded is achieved, so circumferential welding of a rod-like object in a narrow space can be performed by remote control.Therefore, if the welding apparatus of the present invention is used, for example, welding of a boiler superheater can be performed. It is possible to weld and repair damaged areas that are located in the center of clusters of pipes, etc. and cannot be accessed by workers, without having to cut healthy areas, which reduces the cost and time required for repair work. can be significantly reduced by three times, and furthermore, the deterioration in quality of the target product can be kept to a minimum.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the present invention, in which FIG. 1 is a vertical sectional view of a welding device according to an embodiment of the present invention, FIG. 2 is a front view showing a schematic configuration thereof, and FIG. The figure is a perspective view showing an example of a welding device according to an embodiment of the present invention attached to a fixing jig and used for drying, and FIG. 4 shows a state in which the fixing jig is fixed to a tube of a boiler superheater. FIG. 5 is a schematic overall perspective view showing a state in which the present apparatus is applied to tube welding work of a boiler superheater. Also, the 6th
The figure is a schematic perspective view of a boiler superheater for explaining conventional repair work. In the drawing, 21 is a fixing jig, 22m is a tube to be welded, 25a and 25b are clamps, 34a and 34b are overhanging plates, 38 is a board, 39 is a cover, 43 is a slide rod, 49 is an arm, and 50 is a joint 51 is a pin, 52 is a torch holder, 54 is a tension cable, 56 is a tension spring, 57 is a TIG welding torch, 58 is a filler wire tip holder, and 63 is a sheath body.

Claims (1)

[Claims] A plurality of joint bodies are pivotally connected to each other so as to be freely bendable, and each joint body is urged to rotate in one direction and spirally wraps around the welding object, and the tip of the arm a sheath body that guides the arm to the workpiece, and a sheath body that guides the arm to the workpiece, the arm being directed toward the workpiece with the helical lead angle θ inclined at right angles to the longitudinal axis of the workpiece. a drive mechanism that moves the sheath body at a speed V in the direction, and a drive mechanism that moves the sheath body along the longitudinal axis of the welding object at a speed v of Vtanθ in the direction in which the spiral advances in conjunction with the movement of the arm. A welding device characterized by: