JP2020169522A - In-pipe work scaffold - Google Patents

Abstract

To provide an in-pipe work scaffold that is hard to displace laterally even if a worker moves and also is contributed to improve the safety of work.SOLUTION: An in-pipe work scaffold of the present invention is used when working within an inside of a pipe member arranged with a gradient, and comprises a ladder part and an inner surface band coupled to the ladder part. The inner surface band is an annular member energized toward an outside of a circumferential direction, and the ladder part coupled with the inner surface band is made to be fastened at a fixed position of an inside of the pipe member by abutting the inner surface band to an inner surface of the pipe member.SELECTED DRAWING: Figure 1

Description

The present invention relates to an in-pipe work scaffold used for in-pipe work.

Due to its nature, penstocks for hydroelectric power generation and inverted siphons for rivers are installed with a certain slope. For example, a penstock for hydroelectric power generation needs to rotate a water turbine for power generation by the water passing through the pipe, and is installed with a gradient of about 25 to 35 degrees. In such a pipe, operations such as joining pipe members and painting the inner surface of the pipe are performed. In the work, a scaffold is built inside the pipe member, and the worker moves on the scaffold to perform the work.

Conventionally, as a scaffold used for work in a pipe, one provided with a support rope fixed to the upper part of the pipe member and a ladder device suspended from the support rope has been proposed (Patent Document 1).

Japanese Unexamined Patent Publication No. 2007-23494

Since the scaffolding described in Patent Document 1 has a ladder device suspended from a support rope, there is a drawback that the scaffolding is likely to be laterally displaced when an operator moves the ladder device.

An object of the present invention is to provide a scaffold for work in a jurisdiction, which does not easily shift laterally even when an operator moves and contributes to improvement of work safety.

The scaffolding for in-pipe work of the present invention is used for work inside a pipe member installed with a slope, and includes a ladder portion and an inner band connected to the ladder portion. The inner surface band is an annular member urged outward in the circumferential direction, and by bringing the inner surface band into contact with the inner surface of the pipe member, the ladder portion connected to the inner surface band is fixed at a fixed position inside the pipe member. It is designed to be done.

In the scaffolding for in-pipe work of the present invention, the inner surface band urged outward in the circumferential direction is brought into contact with the inner surface of the pipe member, so that the ladder portion connected to the inner surface band is placed at a fixed position inside the pipe member. Since it is fixed, the ladder portion does not easily shift laterally even if the operator moves on the ladder portion. As a result, higher safety than the conventional scaffolding can be ensured.

The perspective view which shows an example of the scaffold for work in a pipe of this invention. The usage state explanatory drawing of the scaffold for work in a pipe of this invention. (A) is an end view of III-III in FIG. 2, and (b) is an enlarged view of part A in (a). (A) is an IV-IV end view of FIG. 2, and (b) is an enlarged view of part B of (a). (A) is a VV end view of FIG. 2, and (b) is an enlarged view of part C of (a). (A) is a VI-VI end view of FIG. 2, and (b) is an enlarged view of part D of (a).

(Embodiment)
An example of the scaffolding for in-pipe work of the present invention will be described with reference to the drawings. As an example, the scaffold for in-pipe work shown in FIG. 1 includes a ladder portion 10, an inner band 20 connected to the ladder portion 10, and a scaffold portion 30 connected to the ladder portion 10. Although omitted in FIG. 1, an inner band 20 similar to the inner band 20 on the upper end side is provided on the lower end side of the ladder portion 10 (see FIG. 2).

As an example, the ladder portion 10 shown in FIG. 1 includes two vertical frames 11 elongated in the longitudinal direction of the pipe member P, and a plurality of footrest rods 12 erected between the two vertical frames 11. The two vertical frames 11 are arranged in parallel with an interval in the width direction of the pipe member P, and the plurality of footrest rods 12 are arranged in parallel with an interval in the length direction of both vertical frames 11. There is.

The footrest rod 12 of this embodiment has washers 13 welded to both ends in the longitudinal direction (see FIGS. 3A and 3B). A nut 14 is welded to each washer 13. The opening of the washer 13 and the nut 14 communicates with the opening of the footrest rod 12.

Each footrest bar 12 is arranged between both vertical frames 11, and is connected to the vertical frame 11 by screwing a bolt 15 inserted from the outside of each vertical frame 11 into a nut 14.

In this embodiment, a flat bar is used as the vertical frame 11, but a vertical frame 11 other than the flat bar can also be used. Further, although a square pipe is used for the footrest rod 12, a pipe other than the square pipe such as a round pipe can also be used.

The length of the ladder portion 10 can be appropriately designed according to the length of the pipe member P, but in any case, it is preferable that the length is set to fit within one pipe member P. By making it shorter than the length of one pipe member P, it is unlikely to interfere with work such as welding and painting. When the length of the ladder portion 10 is long enough to bend due to the weight of the operator or the like, it is preferable to provide the reinforcing jig 40 in the middle portion of the ladder portion 10.

As an example, the reinforcing jig 40 shown in FIG. 1 includes a contact plate 41, a rubber plate 42 provided on the outer surface of the contact plate 41, and a connecting flange 43 erected on the inner surface side of the contact plate 41. ing. The contact plate 41 and the rubber plate 42 are members that are addressed to the inner surface of the pipe member P, and are rolled so that they can easily come into contact with the pipe member P. A reinforcing rib 44 is provided between the abutting plate 41 and the connecting flange 43 so as to intersect the abutting plate 41 and the connecting flange 43.

As shown in FIGS. 3A and 3B, the reinforcing jig 40 is connected to the ladder portion 10 by using bolts 15 and nuts 14 used for connecting the vertical frame 11 and the footrest rod 12. Specifically, the connecting flange 43 of the reinforcing jig 40 is addressed to the outside of the vertical frame 11, and the bolt 15 inserted from the outside of the connecting flange 43 is screwed into the nut 14 located inside the vertical frame 11. It is connected to the ladder portion 10 by.

In this embodiment, two reinforcing jigs 40 are provided at intervals in the longitudinal direction of each vertical frame 11 of the ladder portion 10, but one reinforcing jig 40 is provided for each vertical frame 11. It can be provided one by one or three or more at a time. By providing the same number of reinforcing jigs 40 at the same positions on the left and right vertical frames 11, it is possible to effectively suppress the deflection and rattling of the ladder portion 10.

As shown in FIG. 2, inner surface bands 20 are provided at positions near the upper end and the lower end of the ladder portion 10. The inner band 20 of this embodiment is formed by connecting three strip-shaped members 21 to form an annular shape. In this embodiment, a rolled flat bar is used as the band-shaped member 21. As shown in FIGS. 4A and 4B, a cushioning plate 22 is provided on the outer periphery of the inner band 20. An existing rubber plate or the like can be used for the cushioning plate 22.

At both ends of each strip-shaped member 21, connecting plates 23 used for connecting to the other strip-shaped members 21 are projected inward. Each connecting plate 23 is provided with reinforcing ribs 24 in a direction intersecting the connecting plate 23.

The end faces of the adjacent first and second strip-shaped members 21 are brought into contact with each other without a gap, and the opposing connecting plates 23 are connected by bolts 25 and nuts 26. Similarly, in the second and third strip-shaped members 21, the end faces are brought into contact with each other without a gap, and the opposing connecting plates 23 are connected by bolts 25 and nuts 26.

On the other hand, the third and first strip-shaped members 21 are arranged with a gap S between the end faces, and both connecting plates 23 are connected by bolts (tension bolts) 25 and nuts 26. In this embodiment, the gap S between the third and first strip-shaped members 21 is about 5 cm, but the gap S may be wider or narrower than this.

The diameter of the inner band 20 can be increased or decreased by adjusting the tightening force of the bolt 25 and the nut 26. Specifically, the diameter can be increased by loosening the tightening of the bolt 25 and the nut 26, and the diameter can be reduced by tightening the tightening.

In this embodiment, two connecting plates 27 are projected from the first strip-shaped member 21 at intervals. The connecting plate 27 is a member used for connecting to the ladder portion 10. The connecting plate 27 of this embodiment is a square flat plate provided with a bolt insertion hole, and is welded to the inner surface of the inner surface band 20.

As shown in FIGS. 4A and 4B, in the inner band 20, the connecting plate 27 is superposed on the outside of the vertical frame 11 of the ladder portion 10, and the bolt 15 inserted from the outside is placed inside the vertical frame 11. It is connected to the ladder portion 10 by being screwed into the position nut 14.

As shown in FIGS. 1 and 2, a scaffolding portion 30 is provided at a position near the upper end of the ladder portion 10. In this embodiment, one scaffolding portion 30 is provided for each of both vertical frames 11 of the ladder portion 10.

As an example, the scaffolding portion 30 shown in FIG. 1 includes a front leg member 31, a rear leg member 32, and a work scaffold 33. The front leg member 31 and the rear leg member 32 are support legs that support the work scaffold 33. In this embodiment, a square pipe is used as the front leg member 31, the rear leg member 32, and the work scaffold 33. For the front leg member 31, the rear leg member 32, and the work scaffold 33, materials other than square pipes can be used.

The work scaffold 33 of this embodiment includes three vertical members 33a arranged at intervals and two erection members 33b erected so as to straddle the three vertical members 33a. The number of vertical members 33a can be increased or decreased from three or more. Further, the number of erection materials 33b can be increased or decreased from two or more.

Of the work scaffold 33, the front leg member 31 is welded to the back surface side of the erection member 33b on the front side. Of the work scaffold 33, the leg connecting flange 34 is projected downward on the back surface side of the erection member 33b on the rear side. The upper end side of the rear leg member 32 is addressed to the leg connecting flange 34, and the rear leg member 32 and the work scaffold 33 are connected by fastening the nut 26 to the bolt 25 inserted through both members.

In the work scaffold 33, as shown in FIGS. 5A and 5B, the lower end side of the front leg member 31 is superposed on the outside of the vertical frame 11, and the bolt 15 inserted from the outside is positioned inside the vertical frame 11. As shown in FIGS. 6A and 6B, the lower end side of the rear leg member 32 is overlapped with the outside of the vertical frame 11, and the bolt 15 inserted from the outside is overlapped with the vertical frame. It is connected to the ladder portion 10 by being screwed into the nut 14 located inside the 11.

In this embodiment, the front leg member 31 is made shorter than the rear leg member 32 so that the work scaffold 33 is horizontal. By making the work scaffold 33 horizontal, the worker can easily maintain his / her posture, and as a result, the worker can safely perform various tasks.

In the scaffolding for in-pipe work of this embodiment, since the inner surface band 20, the scaffolding portion 30, and the reinforcing jig 40 are connected to the ladder portion 10 by bolts 15 and nuts 14, each member can be separated from the ladder portion 10. it can.

The manhole formed when the pipe member P is installed is as narrow as about 500 mm in diameter, but by making it possible to separate each member from the ladder portion 10 (the scaffold for work in the pipe can be disassembled) as in this embodiment, It can be smoothly carried in and out of the manhole. In addition, problems such as peeling of paint due to contact of each member with the inner surface of the pipe member P are unlikely to occur.

Further, in this embodiment, since the inner band 20 is composed of a plurality of (three in this embodiment) band-shaped members 21 that can be divided, the inner band 20 can be smoothly carried in and out. ..

Further, in this embodiment, since a flat bar that can be curved to some extent is used as the vertical frame 11, it is carried into the manhole as compared with the case where a highly rigid material that cannot be curved is used as the vertical frame 11. And can be carried out smoothly from the manhole.

(Other embodiments)
In the above embodiment, the case where two inner band 20s are provided is taken as an example, but the number of inner bands 20 may be one or three or more.

In the above embodiment, the case where the scaffolding portion 30 is provided is taken as an example, but since the ladder portion 10 also functions as a scaffolding portion, the scaffolding portion 30 can be omitted.

In the above embodiment, the case where the reinforcing jig 40 is provided is taken as an example, but the reinforcing jig 40 may be provided as needed, and may be omitted when it is not necessary.

The embodiment is an example, and each configuration of the ladder portion 10, the inner band 20, the scaffolding portion 30, and the reinforcing jig 40 may be other configurations within a range that can be achieved with the intended purpose.

(Example of use)
An example of using the scaffold for in-pipe work of the present invention will be described.
(1) With the inner surface band 20 smaller than the inner diameter of the pipe member P, the scaffolding for in-pipe work is carried into the pipe member P.
(2) Loosen the bolt 25 at a desired position, increase the diameter of the inner surface band 20, and bring it into contact with the inner surface of the pipe member P.
(3) When the inner surface band 20 is brought into contact with the inner surface of the pipe member P, the scaffold for working in the pipe is positioned at a predetermined position of the pipe member P by the urging force of the inner surface band 20 outward in the circumferential direction.
(4) The worker puts his / her foot on the ladder portion 10 and the scaffolding portion 30 to perform various operations such as painting and welding.
(5) After the work is completed, the bolt 25 is tightened to reduce the diameter of the inner surface band 20 and separate it from the inner surface of the pipe member P.
(6) After separating the inner surface band 20 from the inner surface of the pipe member P, the scaffold for work in the pipe is removed or moved into the next pipe member P.

The scaffold for work in a pipe of the present invention can be installed inside various pipe members P and used as a scaffold. In particular, it can be effectively used when working inside a pipe member P (tilted pipe member P) installed with a slope, such as a penstock for hydroelectric power generation or a river overpass pipe.

10 Ladder 11 Vertical frame 12 Scaffolding rod 13 Washer 14 Nut 15 Bolt 20 Inner band 21 Band-shaped member 22 Cushion plate 23 Connecting plate 24 Reinforcing rib 25 Bolt 26 Nut 27 Scaffolding plate 30 Scaffolding 31 Front leg material 32 Rear leg material 33 Work foothold 33a Vertical material 33b Elevation material 34 Scaffolding flange 40 Reinforcing jig 41 Abutment plate 42 Rubber plate 43 Connecting flange 44 Reinforcing rib P Pipe member S Gap

The present invention relates to an in-pipe work scaffold used for in-pipe work.

Due to its nature, penstocks for hydroelectric power generation and inverted siphons for rivers are installed with a certain slope. For example, a penstock for hydroelectric power generation needs to rotate a water turbine for power generation by the water passing through the pipe, and is installed with a gradient of about 25 to 35 degrees. In such a pipe, operations such as joining pipe members and painting the inner surface of the pipe are performed. In the work, a scaffold is built inside the pipe member, and the worker moves on the scaffold to perform the work.

Conventionally, as a scaffold used for work in a pipe, one provided with a support rope fixed to the upper part of the pipe member and a ladder device suspended from the support rope has been proposed (Patent Document 1).

Japanese Unexamined Patent Publication No. 2007-23494

Since the scaffolding described in Patent Document 1 has a ladder device suspended from a support rope, there is a drawback that the scaffolding is likely to be laterally displaced when an operator moves the ladder device.

An object of the present invention is to provide a scaffold for work in a jurisdiction, which does not easily shift laterally even when an operator moves and contributes to improvement of work safety.

The scaffolding for in-pipe work of the present invention is used by being installed inside the pipe member when working inside the pipe member installed with a slope, and is connected to the ladder portion and the ladder portion. It has an inner band. The ladder portion has a length that fits in one pipe member. Inner surface band Ru annular member der biased toward the circumferential direction outside. The ladder portion is arranged inside the inner band so as to intersect the inner band. When the curved surface of the inner band facing the inner surface of the pipe member comes into contact with the inner surface of the pipe member without a gap , the inner band is fixed at the contact position of the pipe member and the ladder portion connected to the inner band is connected to the pipe. It is fixed at a position inside the member along the inner surface of the pipe member on the installation surface side .

In the scaffolding for in-pipe work of the present invention, the inner surface band urged outward in the circumferential direction is brought into contact with the inner surface of the pipe member, so that the ladder portion connected to the inner surface band is placed at a fixed position inside the pipe member. Since it is fixed, the ladder portion does not easily shift laterally even if the operator moves on the ladder portion. As a result, higher safety than the conventional scaffolding can be ensured.

The perspective view which shows an example of the scaffold for work in a pipe of this invention. The usage state explanatory drawing of the scaffold for work in a pipe of this invention. (A) is an end view of III-III in FIG. 2, and (b) is an enlarged view of part A in (a). (A) is an IV-IV end view of FIG. 2, and (b) is an enlarged view of part B of (a). (A) is a VV end view of FIG. 2, and (b) is an enlarged view of part C of (a). (A) is a VI-VI end view of FIG. 2, and (b) is an enlarged view of part D of (a).

(Embodiment)
An example of the scaffolding for in-pipe work of the present invention will be described with reference to the drawings. As an example, the scaffold for in-pipe work shown in FIG. 1 includes a ladder portion 10, an inner band 20 connected to the ladder portion 10, and a scaffold portion 30 connected to the ladder portion 10. Although omitted in FIG. 1, an inner band 20 similar to the inner band 20 on the upper end side is provided on the lower end side of the ladder portion 10 (see FIG. 2).

As an example, the ladder portion 10 shown in FIG. 1 includes two vertical frames 11 elongated in the longitudinal direction of the pipe member P, and a plurality of footrest rods 12 erected between the two vertical frames 11. The two vertical frames 11 are arranged in parallel with an interval in the width direction of the pipe member P, and the plurality of footrest rods 12 are arranged in parallel with an interval in the length direction of both vertical frames 11. There is.

The footrest rod 12 of this embodiment has washers 13 welded to both ends in the longitudinal direction (see FIGS. 3A and 3B). A nut 14 is welded to each washer 13. The opening of the washer 13 and the nut 14 communicates with the opening of the footrest rod 12.

Each footrest bar 12 is arranged between both vertical frames 11, and is connected to the vertical frame 11 by screwing a bolt 15 inserted from the outside of each vertical frame 11 into a nut 14.

In this embodiment, a flat bar is used as the vertical frame 11, but a vertical frame 11 other than the flat bar can also be used. Further, although a square pipe is used for the footrest rod 12, a pipe other than the square pipe such as a round pipe can also be used.

The length of the ladder portion 10 can be appropriately designed according to the length of the pipe member P, but in any case, it is preferable that the length is set to fit within one pipe member P. By making it shorter than the length of one pipe member P, it is unlikely to interfere with work such as welding and painting. When the length of the ladder portion 10 is long enough to bend due to the weight of the operator or the like, it is preferable to provide the reinforcing jig 40 in the middle portion of the ladder portion 10.

As an example, the reinforcing jig 40 shown in FIG. 1 includes a contact plate 41, a rubber plate 42 provided on the outer surface of the contact plate 41, and a connecting flange 43 erected on the inner surface side of the contact plate 41. ing. The contact plate 41 and the rubber plate 42 are members that are addressed to the inner surface of the pipe member P, and are rolled so that they can easily come into contact with the pipe member P. A reinforcing rib 44 is provided between the abutting plate 41 and the connecting flange 43 so as to intersect the abutting plate 41 and the connecting flange 43.

As shown in FIGS. 3A and 3B, the reinforcing jig 40 is connected to the ladder portion 10 by using bolts 15 and nuts 14 used for connecting the vertical frame 11 and the footrest rod 12. Specifically, the connecting flange 43 of the reinforcing jig 40 is addressed to the outside of the vertical frame 11, and the bolt 15 inserted from the outside of the connecting flange 43 is screwed into the nut 14 located inside the vertical frame 11. It is connected to the ladder portion 10 by.

In this embodiment, two reinforcing jigs 40 are provided at intervals in the longitudinal direction of each vertical frame 11 of the ladder portion 10, but one reinforcing jig 40 is provided for each vertical frame 11. It can be provided one by one or three or more at a time. By providing the same number of reinforcing jigs 40 at the same positions on the left and right vertical frames 11, it is possible to effectively suppress the deflection and rattling of the ladder portion 10.

As shown in FIG. 2, inner surface bands 20 are provided at positions near the upper end and the lower end of the ladder portion 10. The inner band 20 of this embodiment is formed by connecting three strip-shaped members 21 to form an annular shape. In this embodiment, a rolled flat bar is used as the band-shaped member 21. As shown in FIGS. 4A and 4B, a cushioning plate 22 is provided on the outer periphery of the inner band 20. An existing rubber plate or the like can be used for the cushioning plate 22.

At both ends of each strip-shaped member 21, connecting plates 23 used for connecting to the other strip-shaped members 21 are projected inward. Each connecting plate 23 is provided with reinforcing ribs 24 in a direction intersecting the connecting plate 23.

The end faces of the adjacent first and second strip-shaped members 21 are brought into contact with each other without a gap, and the opposing connecting plates 23 are connected by bolts 25 and nuts 26. Similarly, in the second and third strip-shaped members 21, the end faces are brought into contact with each other without a gap, and the opposing connecting plates 23 are connected by bolts 25 and nuts 26.

On the other hand, the third and first strip-shaped members 21 are arranged with a gap S between the end faces, and both connecting plates 23 are connected by bolts (tension bolts) 25 and nuts 26. In this embodiment, the gap S between the third and first strip-shaped members 21 is about 5 cm, but the gap S may be wider or narrower than this.

The diameter of the inner band 20 can be increased or decreased by adjusting the tightening force of the bolt 25 and the nut 26. Specifically, the diameter can be increased by loosening the tightening of the bolt 25 and the nut 26, and the diameter can be reduced by tightening the tightening.

In this embodiment, two connecting plates 27 are projected from the first strip-shaped member 21 at intervals. The connecting plate 27 is a member used for connecting to the ladder portion 10. The connecting plate 27 of this embodiment is a square flat plate provided with a bolt insertion hole, and is welded to the inner surface of the inner surface band 20.

As shown in FIGS. 4A and 4B, in the inner band 20, the connecting plate 27 is superposed on the outside of the vertical frame 11 of the ladder portion 10, and the bolt 15 inserted from the outside is placed inside the vertical frame 11. It is connected to the ladder portion 10 by being screwed into the position nut 14.

As shown in FIGS. 1 and 2, a scaffolding portion 30 is provided at a position near the upper end of the ladder portion 10. In this embodiment, one scaffolding portion 30 is provided for each of both vertical frames 11 of the ladder portion 10.

As an example, the scaffolding portion 30 shown in FIG. 1 includes a front leg member 31, a rear leg member 32, and a work scaffold 33. The front leg member 31 and the rear leg member 32 are support legs that support the work scaffold 33. In this embodiment, a square pipe is used as the front leg member 31, the rear leg member 32, and the work scaffold 33. For the front leg member 31, the rear leg member 32, and the work scaffold 33, materials other than square pipes can be used.

The work scaffold 33 of this embodiment includes three vertical members 33a arranged at intervals and two erection members 33b erected so as to straddle the three vertical members 33a. The number of vertical members 33a can be increased or decreased from three or more. Further, the number of erection materials 33b can be increased or decreased from two or more.

Of the work scaffold 33, the front leg member 31 is welded to the back surface side of the erection member 33b on the front side. Of the work scaffold 33, the leg connecting flange 34 is projected downward on the back surface side of the erection member 33b on the rear side. The upper end side of the rear leg member 32 is addressed to the leg connecting flange 34, and the rear leg member 32 and the work scaffold 33 are connected by fastening the nut 26 to the bolt 25 inserted through both members.

In the work scaffold 33, as shown in FIGS. 5A and 5B, the lower end side of the front leg member 31 is superposed on the outside of the vertical frame 11, and the bolt 15 inserted from the outside is positioned inside the vertical frame 11. As shown in FIGS. 6A and 6B, the lower end side of the rear leg member 32 is overlapped with the outside of the vertical frame 11, and the bolt 15 inserted from the outside is overlapped with the vertical frame. It is connected to the ladder portion 10 by being screwed into the nut 14 located inside the 11.

In this embodiment, the front leg member 31 is made shorter than the rear leg member 32 so that the work scaffold 33 is horizontal. By making the work scaffold 33 horizontal, the worker can easily maintain his / her posture, and as a result, the worker can safely perform various tasks.

In the scaffolding for in-pipe work of this embodiment, since the inner surface band 20, the scaffolding portion 30, and the reinforcing jig 40 are connected to the ladder portion 10 by bolts 15 and nuts 14, each member can be separated from the ladder portion 10. it can.

The manhole formed when the pipe member P is installed is as narrow as about 500 mm in diameter, but by making it possible to separate each member from the ladder portion 10 (the scaffold for work in the pipe can be disassembled) as in this embodiment, It can be smoothly carried in and out of the manhole. In addition, problems such as peeling of paint due to contact of each member with the inner surface of the pipe member P are unlikely to occur.

Further, in this embodiment, since the inner band 20 is composed of a plurality of (three in this embodiment) band-shaped members 21 that can be divided, the inner band 20 can be smoothly carried in and out. ..

Further, in this embodiment, since a flat bar that can be curved to some extent is used as the vertical frame 11, it is carried into the manhole as compared with the case where a highly rigid material that cannot be curved is used as the vertical frame 11. And can be carried out smoothly from the manhole.

(Other embodiments)
In the above embodiment, the case where two inner band 20s are provided is taken as an example, but the number of inner bands 20 may be one or three or more.

In the above embodiment, the case where the scaffolding portion 30 is provided is taken as an example, but since the ladder portion 10 also functions as a scaffolding portion, the scaffolding portion 30 can be omitted.

In the above embodiment, the case where the reinforcing jig 40 is provided is taken as an example, but the reinforcing jig 40 may be provided as needed, and may be omitted when it is not necessary.

The embodiment is an example, a ladder portion 10, the inner surface band 20, the scaffold section 30, the configuration of the reinforcing fixture 40 may be other configurations in a range capable of attaining the intended purpose.

(Example of use)
An example of using the scaffold for in-pipe work of the present invention will be described.
(1) With the inner surface band 20 smaller than the inner diameter of the pipe member P, the scaffolding for in-pipe work is carried into the pipe member P.
(2) Loosen the bolt 25 at a desired position, increase the diameter of the inner surface band 20, and bring it into contact with the inner surface of the pipe member P.
(3) When the inner surface band 20 is brought into contact with the inner surface of the pipe member P, the scaffold for working in the pipe is positioned at a predetermined position of the pipe member P by the urging force of the inner surface band 20 outward in the circumferential direction.
(4) The worker puts his / her foot on the ladder portion 10 and the scaffolding portion 30 to perform various operations such as painting and welding.
(5) After the work is completed, the bolt 25 is tightened to reduce the diameter of the inner surface band 20 and separate it from the inner surface of the pipe member P.
(6) After separating the inner surface band 20 from the inner surface of the pipe member P, the scaffold for work in the pipe is removed or moved into the next pipe member P.

The scaffold for in-pipe work of the present invention can be installed inside various pipe members P and used as a scaffold. In particular, it can be effectively used when working inside a pipe member P (tilted pipe member P) installed with a slope, such as a penstock for hydroelectric power generation or a river overpass pipe.

10 Ladder 11 Vertical frame 12 Scaffolding rod 13 Washer 14 Nut 15 Bolt 20 Inner band 21 Band-shaped member 22 Cushion plate 23 Connecting plate 24 Reinforcing rib 25 Bolt 26 Nut 27 Scaffolding plate 30 Scaffolding 31 Front leg material 32 Rear leg material 33 Work foothold 33a Vertical material 33b Elevation material 34 Scaffolding flange 40 Reinforcing jig 41 Abutment plate 42 Rubber plate 43 Connecting flange 44 Reinforcing rib P Pipe member S Gap

Claims (6)

In the scaffolding for in-pipe work used when working inside the pipe member
It has a ladder part and an inner band connected to the ladder part.
The inner band is an annular member urged outward in the circumferential direction.
By bringing the inner surface band into contact with the inner surface of the pipe member, the ladder portion connected to the inner surface band is fixed at a fixed position inside the pipe member.
Scaffolding for in-pipe work that is characterized by this. In the scaffolding for work in the jurisdiction according to claim 1.
Two or more inner bands are provided at intervals in the longitudinal direction of the ladder,
Scaffolding for in-pipe work that is characterized by this. In the scaffolding for work in the jurisdiction according to claim 1 or 2.
A reinforcing jig was provided on the ladder to prevent the ladder from bending.
Scaffolding for in-pipe work that is characterized by this. In the scaffolding for in-pipe work according to any one of claims 1 to 3.
A scaffolding section on which workers can rest their feet is provided on the ladder section.
The scaffolding portion includes a support leg and a work scaffold supported by the support leg.
The work scaffold was horizontally supported by the support legs,
Scaffolding for in-pipe work that is characterized by this. In the scaffolding for in-pipe work according to any one of claims 1 to 4.
The inner band, reinforcing jig and scaffolding can be separated from the ladder,
Scaffolding for in-pipe work that is characterized by this. In the scaffolding for in-pipe work according to any one of claims 1 to 5.
The inner band is composed of a plurality of connected band-shaped members.
Each of the strip-shaped members has a size capable of passing through a manhole formed when the pipe member is installed.
Scaffolding for in-pipe work that is characterized by this.

Images