JP7353463B2 - Boiler equipment and boiler furnace wall reinforcement structure - Google Patents

Description

The present invention relates to a boiler apparatus and a reinforcement structure for a boiler furnace wall.

Generally, a boiler body includes a furnace and a cage section, and the furnace walls of the furnace and cage section are composed of a large number of water tubes connected via membrane bars. Since the furnace wall is subjected to pressure within the furnace during operation of the boiler, a backstay is arranged to surround the boiler body to reinforce the furnace wall. In addition, the boiler body is suspended and supported by a steel column via a hanging rod, and the steel column and backstay are connected via seismic ties to prevent the boiler body from shaking in the event of an earthquake. There is.

In a boiler device configured in this way, the furnace wall of the boiler main body expands and contracts due to heat, so the backstay cannot be fixed to the furnace wall, and as described in Patent Document 1, the backstay cannot be connected to the backstay. The tied bar is fixed to the furnace wall. Then, by setting an anchor part on the tie bar as an elongation reference point and welding this anchor part to the furnace wall side, the difference in elongation between the furnace wall and the backstay around the tie bar reference point is absorbed. There is.

Japanese Patent Application Publication No. 2007-127371

However, in the conventional structure described above, the anchor part set on the tie bar is welded to the furnace wall side, so thermal stress due to the temperature difference between the furnace wall and the outside air is concentrated on the welded part of the tie bar, and the boiler equipment There was a problem in that when the start and stop of the tie bar was repeated, cracks were likely to occur in the welded part (fixed part) of the tie bar.

The present invention has been made in view of the above circumstances, and the first object is to provide a boiler device that can suppress weld cracks that occur at the fixing locations of tie bars. An object of the present invention is to provide a reinforcing structure for a boiler furnace wall that can suppress weld cracks occurring at tie bar fixing locations.

In order to achieve the first object, the present invention provides a boiler apparatus including a boiler main body having a furnace wall composed of water tubes, and a backstay surrounding the boiler main body, An anchor plate welded and fixed to the furnace wall; a tie bar supported by the backstay and engaged with the anchor plate with a gap therebetween; and a tie bar that prevents the tie bar from falling off from the anchor plate. and a stopper member for preventing the problem, wherein a plurality of the anchor plates are provided, the plurality of anchor plates are welded and fixed to the furnace wall at two upper and lower positions sandwiching the tie bar, and a pair of anchor plates that protrude in the vertical direction from the tie bar. The anchor plate is characterized in that projecting pieces are formed, and these projecting pieces engage grooves formed in the plurality of anchor plates in a concave and convex manner .

Further, in order to achieve the second object, the present invention provides a reinforcing structure for a boiler furnace wall composed of water pipes, which includes an anchor plate welded and fixed to the boiler furnace wall, and an anchor plate fixed to the boiler furnace wall by welding. A tie bar supported by a backstay that surrounds a furnace wall and engaged with the anchor plate with a gap therebetween; and a stopper member that prevents the tie bar from falling off the anchor plate. , a plurality of the anchor plates are provided, the plurality of anchor plates are welded and fixed to the boiler furnace wall at two upper and lower positions sandwiching the tie bar, and a pair of protruding pieces that protrude in the vertical direction are formed on the tie bar. The anchor plate is characterized in that these protruding pieces are engaged with grooves formed in the plurality of anchor plates .

According to the boiler device and the reinforcing structure for the boiler furnace wall of the present invention, it is possible to suppress weld cracks occurring at the tie bar fixing locations. Note that problems, configurations, and effects other than those described above will be made clear by the description of the embodiments below.

FIG. 1 is a side view showing the overall configuration of the boiler device according to the present embodiment. FIG. 2 is a plan view of the boiler device shown in FIG. 1. FIG. FIG. 2 is a diagram showing the side surface of the boiler body shown in FIG. 1 and the arrangement of the backstay. FIG. 4 is a perspective view of the backstay shown in FIG. 3; FIG. 4 is a cross-sectional view taken along line VV in FIG. 3. FIG. 2 is a perspective view showing the main parts of the reinforcement structure for the boiler furnace wall. FIG. 7 is a front view of the reinforcing structure shown in FIG. 6. Side view of the reinforcement structure shown in Figure 6 FIG. 7 is a vertical cross-sectional view showing the main parts of the reinforcing structure shown in FIG. 6;

Embodiments of the present invention will be described below with reference to FIGS. 1 to 9. FIG. 1 is a side view showing the overall configuration of the boiler device according to the present embodiment, FIG. 2 is a plan view of the boiler device shown in FIG. 1, and FIG. 3 is a diagram showing the arrangement of the side surface of the boiler main body and the backstay shown in FIG. , FIG. 4 is a perspective view of the backstay shown in FIG. 3, FIG. 5 is a sectional view taken along the line VV in FIG. 3, FIG. 6 is a perspective view showing the main parts of the reinforcement structure for the boiler furnace wall, and FIG. 8 is a side view of the reinforcing structure shown in FIG. 6, and FIG. 9 is a longitudinal sectional view showing a main part of the reinforcing structure shown in FIG. 6. In addition, in the following description, each direction of front and back, left and right, and up and down is defined as shown in FIG. 1, 2.

As shown in FIGS. 1 and 2, the boiler device according to the present embodiment includes a boiler main body 1 and a plurality of steel columns 12 that are provided so as to surround the boiler main body 1 and support the boiler main body 1. The boiler main body 1 is suspended from a plurality of steel beams 11 spanning over a plurality of steel columns 12 via a plurality of hanging rods 10 . The boiler main body 1 includes a furnace 2, a cage part 3, and a sub-side wall 4 connecting the furnace 2 and the cage part 3. As will be described later, the furnace 2 is surrounded by a water wall 2a (see FIGS. 6 to 8) formed by welding and fixing water tubes (heat transfer tubes) 7, through which boiler water flows, to each other with a membrane bar 8. . The cage part 3 is also surrounded by a cage wall 3a having the same structure as the water wall 2a, and in the following explanation, the water wall 2a of the furnace 2 and the cage wall 3a of the cage part 3 will be referred to as the boiler furnace wall. 5 will be given.

The furnace 2 and the cage part 3 are connected to a plurality of steel columns 12 provided around the boiler furnace wall 5 via a plurality of seismic ties 13. More specifically, a backstay 20 provided so as to surround the water wall 2a and a steel column 12 are connected by a seismic tie 13, and a backstay 20 provided so as to surround the cage wall 3a is connected to the steel column 12. The steel columns 12 are connected to each other by seismic ties 13.

The backstay 20 is a member for reinforcing the boiler furnace wall 5 against the pressure of combustion gas in the furnace 2 and the cage portion 3, and is made of, for example, H-shaped steel. That is, when the boiler main body 1 is in operation, the water wall 2a of the furnace 2 receives the furnace internal pressure generated by internal combustion air and combustion gas. This furnace internal pressure acts on the water wall 2a and the cage wall 3a in a positive and negative manner, causing the water wall 2a and the cage wall 3a to bulge and deform. Therefore, in order to prevent excessive deformation of the water wall 2a and the cage wall 3a, as shown in FIGS. 20 are placed. For example, as shown in FIG. 5, deformation of the furnace 2 is prevented by surrounding the furnace 2 on all sides with backstays 20 extending in the horizontal direction.

However, since the boiler furnace wall 5 expands and contracts due to heat, the backstay 20 cannot be directly fixed to the boiler furnace wall 5. As shown in FIG. is attached to the water wall 2a (boiler furnace wall 5) of the furnace 2. Hereinafter, a reinforcement structure for the boiler furnace wall 5 using the backstay 20 and the tie bar 30 will be explained with reference to FIGS. 6 to 9.

As shown in FIGS. 6 to 9, the boiler furnace wall 5 has water pipes 7 and membrane bars 8 arranged alternately and welded together in a panel shape, in order to flatten the outer surface of the boiler furnace wall 5. A filler plate 31 is welded and fixed to a predetermined range of the outer surface of the boiler furnace wall 5. A pair of anchor plates 32 are welded and fixed to the filler plate 31 at a predetermined interval in the vertical direction, and a tie bar 30 is arranged between these anchor plates 32. It should be noted that the anchor plates 32 do not necessarily have to be a pair, and the structure may be such that the anchor plates 32 are provided only on one of the upper and lower sides.

The anchor plate 32 is an elongated member whose long axis is in the horizontal direction, and its entire circumference is fixed to the filler plate 31 by welding. The anchor plate 32 and the tie bar 30 are not welded, and a concave groove 32a is formed in the longitudinally central portion of the anchor plate 32 as an engagement portion with the tie bar 30. In addition, a slit 32b extending in the longitudinal direction is formed in most of the anchor plate 32 including the groove 32a, and this slit 32b reduces the effects of thermal deformation due to a temperature difference with the boiler furnace wall 5. It has become.

The tie bar 30 is a plate-shaped member arranged horizontally along the outer surface of the boiler furnace wall 5, and is supported on the outer surface of the boiler furnace wall 5 by a plurality of holding pins 33. As described above, the anchor plate 32 and the tie bar 30 are not welded, and the tie bar 30 has a pair of protruding pieces 30a that are fitted in the grooves 32a of the anchor plate 32 and protrude in the vertical direction. The groove 32a and the protruding piece 30a are engaged with each other with a gap of about several millimeters between them. By welding and fixing the stopper member 34 to the anchor plate 32, the tie bar 30 is prevented from falling off from the anchor plate 32. A standoff 35 is fixed to the outer surface of the tie bar 30, and the backstay 20 is in contact with this standoff 35 (see FIG. 8).

Note that the stopper member 34 only needs to be welded and fixed to at least the anchor plate 32 of the anchor plate 32 and the protrusion piece 30a. For example, even if all the stopper members 34 are welded and fixed to the anchor plate 32 and the protrusion piece 30a, good. Further, in this embodiment, since the pair of anchor plates 32 are arranged one above the other, the two upper stopper members 34 are welded and fixed to the anchor plate 32, and the two lower stopper members 34 are fixed to the protruding piece 30a. It may be fixed by welding.

In the boiler device configured in this way, a protruding piece 30a is formed on the anchor part set on the tie bar 30, and the protruding piece 30a and the groove part 32a of the anchor plate 32 welded and fixed to the filler plate 31 of the boiler furnace wall 5 are connected to each other. By engaging them unevenly, the difference in elongation between the boiler furnace wall 5 and the backstay 20 centered on the reference point of the tie bar 30 is absorbed. At this time, thermal expansion and contraction of the anchor plate 32 welded to the boiler furnace wall 5 side is absorbed by the gap existing between the groove 32a of the anchor plate 32 and the protruding piece 30a of the tie bar 30, so that the anchor plate 32 Temperature followability with respect to the boiler furnace wall 5 is improved, and generation of cracks in the welded portion of the anchor plate 32 can be suppressed. Moreover, because the anchor plates 32 are arranged at two positions above and below across the tie bar 30, and the entire circumference of these anchor plates 32 is welded and fixed to the filler plate 31 of the boiler furnace wall 5, the anchor plates 32 can be made smaller. The strength required for the anchor portion of the tie bar 30 can be ensured.

Since the boiler furnace wall 5 is supported by the steel columns 12 via the backstays 20 connected to the tie bars 30, horizontal vibrations that occur during an earthquake are caused by the vibrations between the backstays 20 and the steel columns 12. It is relaxed by the seismic tie 13 interposed in between. Note that the amount of displacement of the boiler body 1 when an earthquake occurs is larger than that in normal times, and the anchor plate 32 is displaced by an amount that far exceeds the gap between the groove 32a and the protruding piece 30a. 32 and tie bar 30 vibrate integrally.

As explained above, the boiler apparatus according to the present embodiment includes a boiler main body 1 having a boiler furnace wall 5 made up of water pipes 7, a steel column 12 provided around the boiler main body 1, and a boiler main body 1. It includes a backstay 20 that surrounds and extends in the horizontal direction, and a tie bar 30 that supports the backstay 20 on the boiler furnace wall 5, and the steel column 12 and the backstay 20 are connected via a seismic tie 13. Therefore, damage to the boiler main body 1 can be reduced when an earthquake occurs. Then, the anchor part set on the tie bar 30 was separated from the tie bar 30, the anchor plate 32 as the anchor part was welded and fixed to the boiler furnace wall 5, and the protruding piece 30a formed on the tie bar 30 was formed on the anchor plate 32. Since the protruding piece 30a is engaged with the groove 32a with a gap between the grooves 32a and the stopper member 34 is configured to prevent the protruding piece 30a from falling off the groove 32a, there is no need to weld the tie bar 30 to the boiler furnace wall 5. Weld cracks occurring at the 30 fixed locations can be suppressed.

Moreover, because the anchor plates 32 are arranged at two positions above and below across the tie bar 30, and the entire circumference of these anchor plates 32 is welded and fixed to the boiler furnace wall 5, the size of the anchor plate 32 can be reduced and thermal stress can be reduced. The strength required for the anchor portion of the tie bar 30 can also be ensured.

In addition, in the reinforcement structure of the boiler furnace wall 5 according to the present embodiment, the anchor portion (anchor plate 32) serving as the elongation reference point set on the tie bar 30 is separated from the tie bar 30, and the anchor plate 32 is attached to the boiler furnace wall 5. While fixing by welding, the protruding piece 30a formed on the tie bar 30 is engaged with the groove 32a formed on the anchor plate 32 with a gap, and the stopper member 34 prevents the protruding piece 30a from falling off from the groove 32a. With this configuration, there is no need to weld the tie bars 30 to the boiler furnace wall 5, and weld cracks that occur at the fixing locations of the tie bars 30 can be suppressed.

Note that the present invention is not limited to the embodiments described above, and includes various modifications. The embodiments described above have been described in detail to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described.

1 Boiler body 2a Water wall 3 Cage portion 3a Cage wall 4 Sub-side wall 5 Boiler furnace wall (furnace wall)
7 Water pipe 8 Membrane bar 10 Hanging rod 11 Steel beam 12 Steel column 13 Seismic tie 20 Back stay 30 Tie bar 30a Projecting piece 31 Filler plate 32 Anchor plate 32a Groove 32b Slit 33 Holding pin 34 Stopper member 35 Standoff

Claims (4)

A boiler device comprising a boiler body having a furnace wall made up of water tubes, and a backstay surrounding the boiler body,
an anchor plate welded and fixed to the furnace wall;
a tie bar supported by the backstay and engaged with the anchor plate with a gap therebetween;
a stopper member that prevents the tie bar from falling off the anchor plate;
Equipped with
A plurality of the anchor plates are provided,
The plurality of anchor plates are welded and fixed to the furnace wall at two upper and lower positions sandwiching the tie bar,
A boiler device characterized in that a pair of protruding pieces that protrude in the vertical direction are formed on the tie bar, and these protruding pieces engage grooves formed in the plurality of anchor plates in a concave and convex manner. The boiler device according to claim 1,
The boiler apparatus is characterized in that the stopper member is welded and fixed to at least the anchor plate of the anchor plate and the tie bar. The boiler device according to claim 1 or 2,
A boiler device characterized in that a slit is formed in each of the plurality of anchor plates. A reinforcement structure for a boiler furnace wall composed of water pipes,
an anchor plate welded and fixed to the boiler furnace wall;
a tie bar that is supported by a backstay that surrounds the boiler furnace wall and that is engaged with the anchor plate with a gap therebetween;
a stopper member that prevents the tie bar from falling off the anchor plate;
Equipped with
A plurality of the anchor plates are provided,
The plurality of anchor plates are welded and fixed to the boiler furnace wall at two upper and lower positions sandwiching the tie bar,
A reinforcing structure for a boiler furnace wall, characterized in that the tie bar is formed with a pair of protruding pieces that protrude in the vertical direction, and these protruding pieces are engaged with grooves formed in the plurality of anchor plates. .

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