JP2019039578A - Membrane panel partial replacement method - Google Patents

Abstract

To provide a partial exchange method for a membrane panel capable of reducing a cut area of a continuously available region and shortening a work time compatibly when partially exchanging an existent membrane panel.SOLUTION: A partial exchange method for a membrane panel includes the steps of: forming a void by partially cutting an existent membrane panel; newly producing a membrane panel for exchange and a membrane panel for length adjustment; fitting the membrane panel for exchange and the membrane panel for length adjustment into the void; abutting and welding a water pipe of the existent membrane panel and a water pipe of the membrane panel for exchange with a route gap being equal to or less than 1 mm, abutting and welding the water pipe of the existent membrane panel and a water pipe of the membrane panel for length adjustment with a route gap being equal to or less than 1 mm, and abutting and welding the water pipe of the membrane panel for exchange and the water pipe of the membrane panel for length adjustment with a route gap ranging from 2 to 10 mm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a membrane panel partial replacement method for partially replacing an existing membrane panel.

  A membrane panel constituting a water wall and a water cooling duct of a boiler furnace has a flat surface or a curved surface by arranging a large number of water tubes and connecting adjacent water tubes with a plate material called a fin (see, for example, Patent Document 1). ).

  That is, as shown in a front view in FIG. 8, the membrane panel 1 includes a large number of water pipes 2 and fins 3 that connect adjacent water pipes 2 to each other.

  And, when a part of the existing membrane panel is severely deteriorated and cannot fully function, and partially replaced, as described in Patent Document 2, after the severely deteriorated area is cut out, Insert the newly manufactured replacement membrane panel into the trace, and replace the water tube end and fin end of the replacement membrane panel with the remaining water tube end and fin end of the existing membrane panel, respectively. Is connected by butt welding.

JP 2014-55760 A JP 2009-139044 A JP 2014-35174 A

  Generally, when connecting the pipe ends of the water pipes of the membrane panel by butt welding, if the pipe thickness of the water pipe is 3 mm or more, the route gap (route interval) is set to about 2 to 10 mm. (See Patent Document 3).

  On the other hand, as described above, after cutting a severely deteriorated area of the existing membrane panel, a newly manufactured replacement membrane panel is fitted into the trace, and the water tube of the replacement membrane panel is inserted. When connecting the end and the pipe end of the remaining water pipe of the existing membrane panel by butt welding, it is difficult to perform butt welding with the general route gap (2 to 10 mm) as described above.

  This is because the pipe end of the remaining water pipe of the existing membrane panel to be butt welded is slightly deteriorated and the pipe thickness (remaining thickness) is less than 3 mm.

  Therefore, conventionally, as shown in FIGS. 4A, 4B, and 5, butt welding can be performed with a general route gap (2 to 10 mm). 4A is a front view of the existing membrane panel 1 (water pipe 2, fin 3), and FIG. 4B is a front view of the replacement membrane panel 81 (water pipe 82, fin 83). 5 is a view showing a state in which the pipe end of the water pipe 2 and the pipe end of the water pipe 82 are butted together.

  That is, first, as shown in FIG. 4A, when a severely deteriorated region of the existing membrane panel 1 is defined as length L0 × width W0, the tube thickness (residual thickness) is slightly deteriorated adjacent to it. Including a region (length Lr × width W0) where is less than 3 mm, it is cut out together to form a void 84 having a size of length Ls × width W0. As a result, the pipe thickness (remaining thickness) t2 of the pipe end of the remaining water pipe 2 of the existing membrane panel 1 is 3 mm or more.

  Next, as shown in FIG. 4B, a replacement membrane panel 81 is newly manufactured with a dimension of length L8 × width W0. The tube thickness t of the tube end of the water tube 82 of the replacement membrane panel 81 is naturally 3 mm or more (for example, 5 mm or more).

  As a result, when the replacement membrane panel 81 is fitted into the gap 84, the route gap RG8 between the pipe end of the water pipe 2 and the pipe end of the water pipe 82 is set to a general route gap (2 as shown in FIG. -10 mm), and butt welding can be performed.

At this time, the length Ls of the gap 84 and the length L8 of the replacement membrane panel 81 satisfy the following expressions (X1) and (X2).
Ls = RG8 + L8 + RG8 (X1)
2 mm ≦ RG8 ≦ 10 mm (X2)

  However, in the case of this conventional technology, although butt welding can be performed with a general route gap (2 to 10 mm), a functionally continuous region (length Lr × width W0) is cut off. There is.

  On the other hand, technically, even when the thickness of the water pipe is less than 3 mm, butt welding can be performed by setting the root gap to 1 mm or less.

  Therefore, conventionally, it has been considered to cut out only a severely deteriorated region of the existing membrane panel 1 by making it as shown in FIGS. 6A is a front view of the existing membrane panel 1 (water pipe 2, fin 3), and FIG. 6B is a front view of the replacement membrane panel 91 (water pipe 92, fin 93). 7 is a view showing a state in which the pipe end of the water pipe 2 and the pipe end of the water pipe 92 are butted together.

  That is, first, as shown in FIG. 6A, a severely deteriorated region of the existing membrane panel 1 is cut into a length L0 × width W0 to form a gap 94 having a length L0 × width W0. . As a result, the pipe thickness (remaining thickness) t2 of the pipe end of the remaining water pipe 2 of the existing membrane panel 1 is less than 3 mm.

  Next, as shown in FIG. 6B, a replacement membrane panel 91 is newly manufactured with a dimension of length L9 × width W0. The tube thickness t of the tube end of the water tube 92 of the replacement membrane panel 91 is naturally 3 mm or more (for example, 5 mm or more).

  As a result, when the replacement membrane panel 91 is fitted into the gap 94, as shown in FIG. 7, if the root gap RG9 between the pipe end of the water pipe 2 and the pipe end of the water pipe 92 is set to 1 mm or less, the abutment is performed. It becomes possible to weld.

For this purpose, the length L0 of the gap 94 and the length L9 of the replacement membrane panel 91 must satisfy the following expressions (Y1) and (Y2).
L0 = RG9 + L9 + RG9 (Y1)
RG9 ≦ 1mm (Y2)

That is, it is necessary to satisfy the following expression (Y3).
0 mm ≦ L0−L9 ≦ 2 mm (Y3)

  Therefore, in order to satisfy the formula (Y3), the formation of the gap 94 and the manufacture of the replacement membrane panel 91 must be performed very carefully and accurately.

  As a result, in the case of this conventional technique, only the severely deteriorated region of the existing membrane panel 1 needs to be cut out, but there is a problem that the replacement work takes a long time.

  The present invention has been made in view of the circumstances as described above. When partially replacing an existing membrane panel, it is possible to simultaneously reduce the cut-out area of a continuously usable region and the work time. It is an object of the present invention to provide a method for partially replacing a membrane panel.

  In order to solve the above problems, the present invention has the following features.

[1] A membrane panel partial replacement method for partially replacing an existing membrane panel,
A gap forming step of partially cutting off the existing membrane panel to form a gap;
A new manufacturing process for newly manufacturing a replacement membrane panel and a length adjusting membrane panel;
A fitting step of fitting the replacement membrane panel and the length adjustment membrane panel into the gap;
The remaining water pipe of the existing membrane panel and the water pipe of the replacement membrane panel are butt welded with a root gap of 1 mm or less, and the remaining water pipe of the existing membrane panel and the length adjusting membrane panel A butt welding process in which the water pipe of the replacement membrane panel and the water pipe of the length adjusting membrane panel are butt welded at a root gap of 2 to 10 mm. A method for partially replacing a membrane panel.

  [2] The membrane panel partial replacement method according to [1], wherein the length adjusting membrane panel has a length of 20 to 100 mm.

  [3] The membrane panel according to [1] or [2], wherein in the gap forming step, an allowable range in a direction in which the length of the gap is increased is provided for the length of the gap. Partial replacement method.

  In the present invention, when the existing membrane panel is partially replaced, it is possible to reduce both the cut-out area of the continuously usable region and the work time.

It is a figure which shows the existing membrane panel in one Embodiment of this invention, the membrane panel for replacement | exchange, and the membrane panel for length adjustment. In one Embodiment of this invention, it is a figure which shows the state which fitted the membrane panel for replacement | exchange, and the membrane panel for length adjustment in the space | gap of the existing membrane panel. In one Embodiment of this invention, it is a figure which shows the butt | matching state with the water pipe | tube with which the existing membrane panel remains, the water pipe | tube of a replacement membrane panel, and the water pipe | tube of a length adjustment membrane panel. It is a figure which shows the existing membrane panel and replacement | exchange membrane panel in a prior art. In a prior art, it is a figure which shows the butt | matching state of the water pipe | tube with which the existing membrane panel remains, and the water pipe | tube of the membrane panel for replacement | exchange. It is a figure which shows the existing membrane panel and replacement | exchange membrane panel in another prior art. In another prior art, it is a figure which shows the butt | matching state of the water pipe | tube with which the existing membrane panel remains, and the water pipe | tube of the membrane panel for replacement | exchange. It is a membrane panel.

  A membrane panel partial replacement method according to an embodiment of the present invention will be described.

  In one embodiment of the present invention, when an existing membrane panel is partially replaced, a gap is formed by partially cutting the existing membrane panel, and a replacement membrane panel and a length adjusting membrane are newly formed. The replacement membrane panel and the length adjustment membrane panel are fitted into the gap, the remaining water pipe of the existing membrane panel, the water pipe of the replacement membrane panel, and the length The water pipe of the membrane panel for adjustment is butt welded.

  Specifically, as shown in FIGS. 1 (a), (b), (c), FIG. 2, FIG. 3 (a), (b), the following steps are provided.

(S1) Gaps Formation Step As shown in FIG. 1 (a), the existing membrane panel 1 is partially cut to form a gap 4 of length La × width W0. At that time, when the severely deteriorated region of the existing membrane panel 1 is defined as length L0 × width W0, the allowable range Lm (for example, 0 mm) in the direction in which the length of the gap 4 becomes longer than the length La of the gap 4. ≦ Lm ≦ 10 mm), and the length La of the gap 4 may be satisfied as L = L0 + Lm. Thereby, it is not necessary to obtain the accuracy of the formation of the gap as compared with the prior art shown in FIGS. In addition, the allowable range Lm (for example, 10 mm at the maximum) is the length that is cut off because the tube thickness is less than 3 mm in the prior art shown in FIGS. Compared to Lr, the length is very short.

(S2) New manufacturing process As shown in FIG. 1 (b), the replacement membrane panel 11 (water pipe 12, fin 13) of length L1 × width W0 and the length as shown in FIG. 1 (c) A length adjusting membrane panel 21 (water pipe 22, fin 23) of L2 × width W0 is newly manufactured.

(S3) Inserting Step As shown in FIG. 2, the replacement membrane panel 11 and the length adjusting membrane panel 21 are inserted into the gap 4 formed in the existing membrane panel 1.

(S4) Butt welding step In FIG. 3 (b), as shown in the butted state between the pipe end of the remaining water pipe 2 of the existing membrane panel 1 and the pipe end of the water pipe 12 of the replacement membrane panel 11, Butt welding is performed with the pipe end of the water pipe 2 and the pipe end of the water pipe 12 being the root gap RG3. At that time, the tube thickness t of the water tube 12 of the replacement membrane panel 11 is naturally 3 mm or more (for example, 5 mm or more), but the tube thickness of the remaining water tube 2 of the existing membrane panel 1 remains. (Remaining thickness) Since t2 is less than 3 mm, butt welding is performed with the root gap RG3 being 1 mm or less.

  Further, in FIG. 3 (a), the water pipe 2 of the water pipe 2 is shown in a butted state with the pipe end of the remaining water pipe 2 of the existing membrane panel 1 and the pipe end of the water pipe 22 of the membrane panel 21 for length adjustment. Butt welding is performed with the pipe end and the pipe end of the water pipe 22 as the root gap RG1. At that time, the tube thickness t of the water pipe 22 of the length adjusting membrane panel 21 is naturally 3 mm or more (for example, 5 mm or more), but the pipe at the pipe end of the remaining water pipe 2 of the existing membrane panel 1. Since the thickness (remaining thickness) t2 is less than 3 mm, butt welding is performed with the root gap RG1 being 1 mm or less.

  Further, in FIG. 3 (a), the pipe end of the water pipe 22 and the pipe end of the water pipe 22 of the replacement membrane panel 11 and the pipe end of the water pipe 22 are shown as shown in FIG. Butt welding is performed with the pipe gap of the water pipe 12 as the root gap RG2. At that time, the tube thickness t of the tube end of the water tube 12 of the replacement membrane panel 11 and the tube thickness t of the tube end of the water tube 22 of the length adjusting membrane panel 21 are also 3 mm or more (for example, 5 mm or more). Butt welding is performed with a root gap RG2 of 2 to 10 mm.

At this time, the length La of the gap 4, the length L1 of the replacement membrane panel 11, and the length L2 of the length adjustment membrane panel 21 satisfy the following formulas (A1) to (A4). .
La = RG1 + L2 + RG2 + L1 + RG3 (A1)
RG1 ≦ 1mm (A2)
2 mm ≦ RG2 ≦ 10 mm (A3)
RG3 ≦ 1mm (A4)

That is, the following equation (A5) may be satisfied.
2 mm ≦ La− (L1 + L2) ≦ 12 mm (A5)

  This means that the permissible ranges of the length La of the gap 4, the length L1 of the replacement membrane panel 11, and the length L2 of the length adjustment membrane panel 21 are wide. Therefore, it is possible to greatly reduce the work time required for forming the gap 4 and manufacturing the replacement membrane panel 11 and the length adjusting membrane panel 21.

  The length L2 of the length adjustment membrane panel 21 is not limited, but the length L2 is preferably 20 mm or more in order to avoid the proximity of the weld bead. On the other hand, if the length L2 is too long, the weight will increase. The length L2 is preferably 100 mm or less because the on-site mounting length is increased and the working efficiency is lowered. That is, the length L2 of the length adjusting membrane panel 21 is preferably 20 to 100 mm.

  Moreover, about the membrane panel 21 for length adjustment, the thing of length which differs in predetermined length space | interval (for example, 5 mm space | interval) is prepared beforehand, and based on said (A1)-(A5) Formula, it is appropriate. The length-adjusting membrane panel 21 may be selected, or the length La of the gap 4 and the length L1 of the replacement membrane panel 11 are measured, and the (A1) to (A Based on the formula (A5), the membrane panel 21 for adjusting the length of an appropriate length may be manufactured.

  Thus, in this embodiment, when the existing membrane panel is partially replaced, it is possible to achieve both reduction in the cut-out area of the region that can be continuously used and reduction in work time.

DESCRIPTION OF SYMBOLS 1 Existing membrane panel 2 Existing membrane panel water pipe 3 Existing membrane panel fin 11 Replacement membrane panel 12 Replacement membrane panel water tube 13 Replacement membrane panel fin 21 Length adjustment membrane panel 22 Length adjustment Membrane Panel Water Pipe 23 Length Adjustable Membrane Panel Fin 81 Replacement Membrane Panel 82 Replacement Membrane Panel Water Pipe 83 Replacement Membrane Panel Fin 91 Replacement Membrane Panel 92 Replacement Membrane Panel Water Pipe 93 Replacement membrane panel fins

Claims (3)

A membrane panel partial replacement method for partially replacing an existing membrane panel,
A gap forming step of partially cutting off the existing membrane panel to form a gap;
A new manufacturing process for newly manufacturing a replacement membrane panel and a length adjusting membrane panel;
A fitting step of fitting the replacement membrane panel and the length adjustment membrane panel into the gap;
The remaining water pipe of the existing membrane panel and the water pipe of the replacement membrane panel are butt welded with a root gap of 1 mm or less, and the remaining water pipe of the existing membrane panel and the length adjusting membrane panel A butt welding process in which the water pipe of the replacement membrane panel and the water pipe of the length adjusting membrane panel are butt welded at a root gap of 2 to 10 mm. A method for partially replacing a membrane panel.   The partial replacement method for a membrane panel according to claim 1, wherein the length adjustment membrane panel has a length of 20 to 100 mm.   The method for partially replacing a membrane panel according to claim 1 or 2, wherein, in the gap forming step, an allowable range in a direction in which the length of the gap is increased is provided for the length of the gap.

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