JPH02229362A - Suspended furnace scaffold - Google Patents

Abstract

PURPOSE:To enable the easy going up and down of the whole scaffold device while keeping it horizontal by mounting a scaffold device to a plurality of step rods suspended from the beams of the upper part through up-down jacks. CONSTITUTION:Four step rods 3 supported by supporting devices 2b provided in the middle of Top beams 2 are suspended near each corner of a boiler 1 to nearly reach a furnace bottom 1b. A number of step rods 3 are joined to each other to the height of the furnace, and a scaffold 5 is formed in one floor type or rectangular shape, a plurality of guide rollers for preventing horizontal contact are mounted on the side surfaces. Up-down jacks 4 for raising and lowering the scaffold 5 are mounted on the scaffold 5 in the state engaged with the step rods 3, and driven and controlled by oil pressure. Hence, the labor and time for assembling and disjoining work for the scaffold can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a suspended in-furnace scaffold used for maintenance and inspection work in a large boiler furnace such as a thermal power plant. However, the present invention is not limited to this, and can also be applied to maintenance and inspection inside ship holds and building structures.

Conventional technology In such conventional in-furnace scaffolding equipment, which is mainly erected during maintenance and inspection of the furnace walls and burner boxes in large boiler furnaces, a plurality of single-tube columns are placed on the side walls on the bottom of the boiler furnace. Arrange them at appropriate intervals along the inner circumference, and first
A horizontal single pipe with a cross section is passed horizontally and assembled onto a single pipe pillar.

Scaffolding boards are then placed on top of this horizontal single pipe and secured with connectors such as wire to form a scaffold.

Conventionally, in this manner, the second and higher stages of in-furnace scaffolding are successively erected toward the upper part of the boiler furnace.

However, as the capacity of the boiler itself increases, the scaffolding has to be assembled several tens of meters in height, in some cases approaching 100 meters, and a large amount of materials must be brought in from a limited area at the bottom of the furnace and assembled. It won't happen. As a result, the actual situation is that assembling and dismantling scaffolding requires a lot of labor and time, making it impossible to shorten the construction period and causing an increase in construction costs and a decrease in work efficiency. Therefore, as one of the countermeasures,
In the scaffold disclosed in No. 2, as shown in FIG. 8, the scaffold 3 is not fixedly installed in a tower shape inside the boiler furnace, but the scaffold 3 is suspended from the boiler by means of hanging means made of wire ropes 4. A scaffold device 3 arranged so as to be able to rise and fall within the furnace, that is, formed into a cross-shaped plane, is suspended by a wire rope 4, and the other end of the wire rope 4 is attached to a beam 2, so that the load of the scaffold 3 is Beam 2
This wire rope 4 is configured to be supported by a plurality of wire rope winding drums 6 attached to the side of the scaffold 3, and by adjusting the amount of wire winding, the scaffold 3 can be raised and lowered. 2 have been developed.

Problems to be Solved by the Invention Although the technique described above certainly reduces the number of scaffold construction materials brought into the furnace, there are, however, the following problems.

That is, since the suspension of the scaffold 3 is done by winding the wire rope 4, the drum 6 is used to hold the scaffold 3 horizontally.
During the movement of the scaffold 3, the winding speed of the plurality of drums 6 mainly fluctuates, the unbalanced load of the wire rope 4 (or the drum 6 (unbalanced load), the scaffolding 3 itself is likely to sway or tilt, which is dangerous.

In this case, even if the guide rollers 5 on the side surfaces of the scaffold 3 eliminate the vibration in the horizontal direction, they are not very effective against the vibration in the vertical (inclination) direction.

Further, the wire rope 4 is generally vulnerable to fire, and it is necessary to take sufficient precautions against welding sparks and insulation measures in the vicinity.

Moreover, with this method of in-reactor scaffolding, even if the scaffolding needs to be multi-tiered in the vertical direction, it is not possible due to its structure; It is only possible to adjust the height to the inspected position by moving the scaffolding of the platform up and down.

On the other hand, even if multiple stages of scaffolding are installed inside the reactor,
In other words, even if the scaffolding is suspended in stages from the upper tier to the lower tier, wire ropes for hanging are required for each tier or each tier, and the higher the scaffold, the more wire ropes are required. As a result, the scope of maintenance and inspection work is restricted by the wire rope, and the safety of workers is not ensured.

Means for Solving the Problems In order to solve such conventional problems, the present invention provides a suspended furnace scaffolding system in which a plurality of step rods suspended from an upper beam inside a boiler furnace are installed. At least one stage or more of scaffolding equipment is installed via a down jack, and the scaffolding equipment can be raised and lowered relative to the step rod by operating an up-down jack, and the step rod has a large number of inverted conical steps in the vertical direction. The up-down jack has claw-like grooves formed at equal intervals and continuously, and which engage with the notches formed between the steps, at each end of the relatively expandable cylinder and rod. It has a collet attached.

Operation According to this method, the relative expansion and contraction (
By vertical) movement, the claw-shaped collets attached to each end can be engaged in stages with the notches formed between the steps of the step rod hanging inside the boiler furnace, so this jack can be used as an intervening mechanism. In this way, the entire scaffolding device consisting of one or more stages can be easily raised and lowered while maintaining a horizontal state.

EXAMPLES Below, examples of the present invention will be described in detail with reference to FIGS. 1 to 6.

However, according to the present invention, in the furnace of a large boiler l installed in a thermal power plant, etc., the upper (TOP)
At least one stage of scaffolding (device) 5 is attached to a plurality of step rods 3 hanging from the beam 2 via up-down jacks 4.

That is, as shown in FIG. 1, the main body of the boiler 1 is
It is suspended by a hanging device (not shown) of the TOP beam 2 attached to the top of the boiler l and located at the top of the boiler l. Preferably, there are four step rods 3 supported by a support device 2b provided in the middle of the TOP beam 2 near each corner in the boiler 1 which is composed of approximately four furnace walls 1a. It hangs down and almost reaches the bottom of the furnace tb.

The structure of these step rods 3 includes a large number of inverted conical steps (or pieces) in the vertical direction as shown in FIG.
3a are continuously carved at regular intervals, and the continuous cross-sectional shape has a sawtooth shape, and a notch 3b is formed between each step.

Further, the total length of each rod is set to an appropriate length, and by adding a large number of rods 3, it is made to match the height inside the boiler l furnace.

In this case, the two methods of setting the step rod 3 into the boiler 1 furnace will be explained based on FIGS. 3 and 4, respectively. The first method (see FIG. 3) is The through hole goes through Ichiro of the housing IC! A sleeve 1e is attached to the sleeve 1e, and a large number of step rods 3 are connected to the upper side of the TOP beam 2 of the boiler l through the sleeve 1e.
Boiler! Insert it into the lower part of the furnace and insert it into the furnace bottom 1b.
It is something that has been lowered to

Note that during normal operation of the boiler I, a sealing Mlf is attached to the upper part of the through hole 1d to maintain airtightness.

Moreover, in the figure, the code|symbol 1g is a ceiling pipe.

On the other hand, in the second method (see Fig. 4), a winch 2c is installed above the TOP beam 2, and the step rod 3 is hoisted upward by the winch 2a on the bottom tb side of the wire rope 2d. , and are installed through the sleeve 1e of the ceiling housing 1c while adding them one after another.

In either case, the finally assembled step rod 3 is firmly fixed to the TOP beam 2 via the support device 2b (see FIG. 1).

In addition, as shown in Figure 5, for the latter method, the hearth bottom 1
There is a hearth bottom manhole 1h in the furnace wall 1a around part b, and a loading frame 5a is provided in front of it, and a step rod 3
Scaffolding materials 5b including the materials are carried in through this manhole 1h.

Further, as shown in FIGS. 5 and 6, the structure of the up-down jack 4 that allows the scaffold 5 to be raised and lowered with respect to the step rod 3 is composed of a relatively expandable cylinder 4a and a rod 4b, A rod 4b is attached to a piston 4c that partitions the inside of the cylinder 4a body into two chambers through which hydraulic oil flows in and out of each other. This means that
By feeding the jab, the integrally combined cylinder 4a and rod 4b can extend and contract with each other,
By controlling this movement, the lifting and lowering operations of the scaffold 5, which will be described later, are performed.

As clearly shown in FIGS. 6(a) to 6(c), in the step rod 3, a claw-shaped core 4d that engages with the notch 3b formed between the steps 33 is connected to the cylinder 4a and the rod 4b. attached to the extended end of the
In the figure, as an example, the cylinder 4a is placed at the top and the rod 4b is placed at the bottom, so the collets 4d are attached to the upper end of the cylinder 4a and the lower end of the rod 4b, respectively.

Moreover, each collet 4 of these cylinder 4a and rod 4b
At the attachment part d, the collet 4d is inserted from the notch part 3b, contrary to the engagement of the step rod 3 with the notch part 3b.
A spring mechanism or a link mechanism (not shown) for pulling the collet 4d itself in the horizontal direction is built in so that the collet 4d can be removed.

Therefore, if there are four such ab-down jacks 4 corresponding to the step rods 3, then the. Four are placed near each corner! The shape of the scaffolding device 5 (see Fig. 1) to be fixed is formed into a l-floor shape that covers almost the entire inner plane of the boiler (1), or a flat face shape with an opening in the center.
A plurality of guide rollers 5c (see FIG. 5) for preventing horizontal contact (collision) with the furnace wall 1b are attached to the peripheral side surface thereof. Furthermore, this scaffold 5 has a small number of workers and others.
A basket and its elevator 115d (see Figure 1) are installed to allow people to carry out equipment for maintenance and inspection.

It goes without saying that a movable maintenance/inspection robot (not shown) may be mounted on the scaffold 5 from the viewpoint of simplicity and labor saving.

Next, its effect will be explained in detail.

As a preparatory stage, the necessary materials 5b for the scaffolding device 5 are carried into the boiler 1 furnace through the hearth bottom manhole 1h provided with a material carrying frame 5a, and the scaffold 5 is assembled on the hearth bottom ib.

Along with this, a large number of step rods 3 are added from the ceiling housing 1c to the lower part of the boiler 1 furnace, or the step rods 3 are added while being hoisted to the housing lc by hoisting the wire lobes 2d from the furnace bottom 1b. method, or the one that can reduce work effort and time, and build an integrated step rod 3 in each furnace corner according to the height of the boiler.

Then, by incorporating each step rod 3 into an up-down jack 4 provided on the scaffold 5, a scaffold device 5 that can be raised and lowered by operating the up-down jack 4 is completed.

Therefore, in the operation stage, the function and action of the jack 4 will be explained based on FIGS. 6(a) to (e).
) The figure shows the stage when the scaffold 5, which is stationary on the hearth bottom tb, starts to rise, the figure (b) shows the stage during the upward movement, and the figure (c) shows the stage after completing one step of the rise. First, as shown in the figure (a), an appropriate pressure (
By supplying hydraulic oil of the same amount as above and simultaneously discharging the hydraulic oil from the lower chamber, the piston 4c that partitions the inside of the cylinder 4a into two chambers, that is, the rod 4b, tends to be pushed downward, and the cylinder 4a itself tries to be pushed upward.

At this time, the collet 4d on the rod 4b side that meshes with an arbitrary notch 3b of the step rod 3 as shown in the figure is obstructed by the upper end surface of the step 3a shown by diagonal lines in the figure, and the piston 4c under pressure is Further downward movement of the rod 4b connected to is restricted.

At the same time, the side surface of the step 3a that the collet 4d provided at the end of the cylinder 48 comes into contact with is shaped like an inverted cone and is not subject to any major hindrance. Can move upwards without resistance.

Therefore, with respect to the stopped rod 4b, the cylinder 4a
is a relatively upward movement, and due to this,
It becomes possible to raise the scaffold 5.

Next, as shown in the diagram (b), hydraulic oil is continuously injected into the upper chamber, and when the supply reaches a certain level, the cylinder 48 body is moved one level higher than in the diagram (a). 3
The collet 4d of the cylinder 4a engages with the notch 3b of the step 3a again, and is temporarily stopped at that position.

During these strokes, the step rod 3 is
In the case of a book, each of the steps 3a would support approximately 1/4 of the total load of the scaffolding 5 through the upper end surface of the steps 3a indicated by diagonal lines in the figure, and this load would be transmitted to the TOP beam 2, and finally the support column 2.
8 will be held.

Subsequently, as shown in the figure (c), by discharging the hydraulic oil from the upper chamber of the cylinder 48 body and simultaneously supplying the hydraulic oil to the lower chamber, the collet 4d on the cylinder 4a side is discharged as described above. Due to the engagement and the rod 4b being gradually pushed up by the piston 4C, the scaffold 5
The support of the load shifts from the step 3a indicated by diagonal lines in the figure (b) to the upper end surface of the step 3a indicated by the shaded lines in figure (c), so that the cylinder 4a side is in a fixed state.

Therefore, the rod 4b moves upward without resistance, and the collet 4d provided at the end of the rod 4b is inserted into the notch 3b of the step 3a, which is one step higher than the step 3a indicated by diagonal lines in the figures (a) and (b). can be meshed with.

Therefore, for the cylinder 4a in a stopped (fixed) state,
The rod 4b moves relatively to contract.

However, during this period, the scaffolding 5 does not move and remains stationary.

By repeating the above-described steps in sequence, the scaffold 5 can be raised freely, and the predetermined inspection position can be accurately reached.

On the other hand, when lowering the scaffold 5, it is sufficient to perform the operation opposite to the above-mentioned process.
This may hinder the downward movement of each collet 4d, however, according to this embodiment, each collet 4d
As mentioned above, the cylinder 4a and the rod 4b can be retracted in the horizontal direction through a spring mechanism or a link mechanism, etc. Under this operation, both the cylinder 4a and the rod 4b can extend and contract while disappearing from the upper end surface of each step 3a. , the entire scaffold 5 can be lowered smoothly.

In addition, by adopting a hydraulic system for the up-down jack 4 as described above, even if the scaffold device 5 has a large weight, it can be easily moved by hydraulic pressure, and it also has good operability and controllability. Therefore, even if a large number of jacks 4 are used, it is possible to supply and adjust the same amount of oil and hydraulic pressure to all jacks 4 at the same time, and thereby the scaffold 5 can be held horizontally at all times. It can be raised and lowered while

Since it is possible to use a step rod-type hanging type in-furnace scaffold that is equipped with a freely adjustable up-down jack, it is possible to reduce the labor and time for assembling and dismantling the scaffold.

In addition, the amount of vertical movement of the scaffold is the same for each step rod, and the solid step rods support the scaffold in both the horizontal and vertical directions, thereby reliably reducing the occurrence of shaking or tilting of the scaffold itself in the reactor. Can be done.

Further, since the step rod has a higher cross-sectional strength and heat resistance than a wire rope, it is strong against fires such as welding sparks in the vicinity, and has sufficient insulation measures.

Furthermore, it is possible to reduce the number of complicated and dangerous accessories such as wire ropes within the scaffold.

Therefore, the workability, functionality, and safety of the scaffolding inside the reactor are improved.

Moreover, as shown in Fig. 7, one scaffold is installed for inspection and repair of the superheater and reheater in the upper part of the furnace, and the other is used for inspection and repair of the furnace walls in the middle and lower part of the furnace. It is also possible to install one scaffold separately, and therefore, multiple stages of scaffolding can be installed at arbitrary intervals within the allowable range of the diameter, number, strength, etc. of the step rods.

Furthermore, mutual communication between the scaffolds in the vertical direction is facilitated by baskets (gondolas) mounted on each scaffold, reducing labor by half.

Furthermore, each of these scaffolds can be moved up and down independently, and the maintenance inspection section of the inspected area can be divided, making it possible to significantly shorten the work time.

[Brief explanation of the drawing]

Fig. 1 is an external view showing an example of a hanging type reactor scaffold according to the present invention, Fig. 2 is an external view showing an example of a step rod according to the present invention, and Fig. 3 is an external view showing an example of a step rod setting method according to the present invention. Fig. 4 is a sectional view of the Ichiro structure showing another setting method, Fig. 5 is an enlarged sectional view of the part ■ in Fig. 1, and Fig. 6 is an example of the upward stroke of the up-down jack with respect to the step rod. (
a) Schematic diagram of the stage of starting the ascent of the scaffolding device, (b)
is a schematic diagram of the stages during the upward movement of the scaffolding device, and (c) is the upward movement of the scaffolding device! FIG. 7 is an external view showing an example of a case where the scaffolding device according to the present invention is installed in multiple stages. FIG. 8 is a schematic cross-sectional view showing a hanging type in-furnace scaffold using a conventional wire rope method. It is a diagram. 1... Boiler, 2... (TOP) Beam, 3... Step rod, 3a... Step, 3b... Notch, 4... Up/down jack, 4a... Cylinder, 4b... Rod, 4d.・Correzuto, 5...Scaffolding (device). (Other names) *1 Figure 1: Boiler 2;

Claims (1)

[Claims] At least one stage or more of scaffolding equipment is attached via an up-down jack to multiple step rods hanging from the upper beam in a boiler furnace of a thermal power plant, etc., and the scaffolding equipment is raised and lowered with respect to the step rods. The step rod can be raised and lowered by operating a jack, and the step rod has a large number of inverted cone-shaped steps continuously and evenly spaced in the vertical direction, and the up-down jack has a cylinder and rod that are relatively extendable and retractable. A suspended furnace scaffold, characterized in that a claw-like collet that engages with a notch formed between the steps is attached to each end of the step.