JPS597890A - Supporting device for heat-transmitting pipe - Google Patents

Abstract

PURPOSE:To enhance supporting strength and contrive to prevent resonance of heat-transmitting pipes, by supporting each of the heat-transmitting pipes by a horizontal supporting plate. CONSTITUTION:The horizontal supporting plate 16 in at least one stage with respect to the direction of height of the heat-transmitting pipes 12 fitted with fins 13 is placed orthogonally to the pipes 12, and, in a direction orthogonal to the flowing direction of a waste gas, vertical supporting plates 18 are placed orthogonally to the horizontal supporting plate 16. Accordingly, supporting strength for the elongated and enlarged heat-transmitting pipes is enhanced, and it is contrived to prevent resonance of the heat-transmitting pipes, particularly the finned ones which are difficult to support.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat transfer tube support device, and particularly to a heat transfer tube support device suitable for supporting finned heat transfer tubes of a waste heat recovery boiler that recovers heat in gas turbine exhaust gas and preventing resonance due to gas flow. Regarding equipment.

Combined cycle power plants have recently been attracting attention as a part of high-efficiency power generation. This plant first generates electricity using a gas turbine, then recovers the heat in the exhaust gas discharged from the gas turbine in a waste heat recovery boiler, and uses the steam generated by the boiler to operate a steam turbine to generate electricity. In addition to high power generation efficiency, this plant has the advantage of high load responsiveness, which is a characteristic of gas turbines, and can sufficiently respond to sudden increases in power demand.

Figure 1 shows waste heat recovered from turbine exhaust gas.

The structure of the recovery boiler is shown. In the figure, turbine exhaust gas G is superheater 1. The exhaust gas passes through a high-pressure evaporator 2 to a denitrification device 3 to remove nitrogen oxides (NOx) from the exhaust gas. Next, the exhaust gas is passed through a high-pressure evaporator 4. High pressure economizer 7, low pressure evaporator 8. It is discharged through a low-pressure economizer 11. The high-pressure steam S and low-pressure steam S2 generated during this time are used as a power source for a steam turbine and an internal heat source. In the figure, numerals 5 and 9 indicate a high-pressure drum and a low-pressure drum, respectively, and numerals 6 and 10 indicate downcomer pipes. The waste heat recovery boiler configured as described above is arranged in a gas flow path through which gas turbine exhaust gas passes.

In other words, a waste heat recovery boiler recovers heat by arranging a large number of heat transfer tube groups such as an evaporator and nine economizers in the gas flow, but as the waste heat recovery boiler becomes larger, the height of these heat transfer tube groups has It becomes something as long as lOm or longer.
Preventing resonance due to gas flow in these heat transfer tube groups has become a problem. Vibration of heat exchanger tubes is caused by a decrease in the strength of the heat exchanger tube as the tube itself becomes longer, which means that the tube becomes easier to bend, and disturbances in the gas flow such as Karman vortices act to promote this and generate resonance. It is believed that.

The object of the present invention is to provide a device which has been constructed in view of two problems, and which increases the holding strength of an enlarged heat exchanger tube and prevents resonance of a finned heat exchanger tube which is particularly difficult to hold. It is in.

In short, this invention forms at least one horizontal support plate in the height direction of the finned heat exchanger tube and arranges it perpendicular to the heat exchanger tube, and furthermore, the horizontal support plate is arranged perpendicular to the exhaust gas flow direction. The structure is such that vertical support plates are arranged to prevent the occurrence of resonance in the heat exchanger tubes.

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 2 and 3, reference numeral 12 is a heat transfer tube constituting the evaporator 2 economizer, and fins 13 are attached to it to improve heat transfer efficiency. In FIG. 2, reference numerals 14a and 14b indicate a central horizontal support plate that is integrated by welding 15, and a divided piece 14a' formed in advance.
, 141; are respectively arranged from both sides of the heat exchanger tube 12, and the contact surfaces are attached by welding 5. Next, support plates are attached to the heat exchanger tubes in the row adjacent to the heat exchanger tubes to which the central horizontal support plate is attached in the following manner.

In FIG. 3, reference numeral 16 denotes a side horizontal support plate, in which a substantially U-shaped notch 16a is formed so as to engage with the heat exchanger tubes 12, and after each heat exchanger tube 12 is arranged with respect to this notch 16a, Welding is performed by bringing the leading edge 16b into contact with the central horizontal support plate. In this case, the horizontal support plates are directly connected to each other.

Alternatively, it is preferable to interpose the round rod 17 to make the connection. A connection method using a round bar will be explained with reference to FIG. For example, to explain a round bar placed between the side horizontal support plate 16 and the center horizontal support plate 14a, the round bar 17 is welded and connected only to the side of the center horizontal support plate 14a, and the side horizontal support plate 1
6 is placed and then connected to this round bar 17 by spot welding or the like.

As described above, by connecting the side horizontal support plates one after another to the central horizontal support plate, an integrated horizontal support plate is formed as a whole, and this horizontal support plate is arranged in one or more stages in the height direction of each heat exchanger tube. Deploy.

FIG. 5 shows the arrangement of vertical support plates that makes the resonance prevention of the heat exchanger tubes more effective and the support more reliable.

In the figure, reference numeral 18 denotes a vertical support plate, which is disposed along the flow of exhaust gas G and perpendicular to the horizontal support plate formed integrally. This vertical support plate 18 is formed as a single flat plate and is positioned sequentially according to the assembly process. When the heat exchanger tubes are arranged in a staggered manner as shown in the figure, the heat exchanger tubes are bent into a planar substantially corrugated shape to avoid the heat exchanger tubes. Reference numeral 19 indicates a support fitting attached to the heat exchanger tube adjacent to the vertical support plate 18. After the approximately U-shaped notch is inserted into the heat exchanger tube, the end portion is welded to the vertical support plate and the vertical support is attached. This is a drawing showing a support plate.

By carrying out this invention, the elongated heat exchanger tube is effectively supported by the horizontal support plate, increasing the strength of the heat exchanger tube itself, and increasing the natural frequency of the heat exchanger tube to prevent resonance phenomena.

In addition, by arranging a vertical support plate in addition to the horizontal support plate, the gas can be rectified more effectively, and vibrations of the heat exchanger tubes can be effectively prevented from occurring. I can do it.

[Brief explanation of the drawing]

Figure 1 is a side view of the boiler showing an outline of the waste heat recovery boiler, Figure 2 is a plan view of the horizontal support plate showing the installation status of the central horizontal support plate, and Figure 3 is the installation of the side horizontal support plates. is a plan view of the support plate showing the state, FIG. 4 is a sectional view taken along line A-A in FIG. 3, FIG. 5 is a perspective view showing the mounting state of the vertical support plate, and FIG. FIG. 12...Heat transfer tube 13...Fin 14a, 14b...Central horizontal support plate 16...
...Side horizontal support plate 17...Round bar 18...Vertical support plate 19...Support metal fittings

Claims (1)

[Claims] 1. In a device that supports finned heat exchanger tubes placed in a high-temperature gas flow, a horizontal support plate is provided so as to be orthogonal to the height direction of the heat exchanger tubes located in the vertical direction. 1. A heat exchanger tube support device characterized by forming a heat exchanger tube and having one or more stages. 2. The horizontal support plate is composed of a central horizontal support plate attached to a predetermined row of heat exchanger tube groups, and side horizontal support plates connected in series around the central horizontal support plate. A heat exchanger tube support device according to claim 1. 3゜ A round bar is placed between the central horizontal support plate, the side horizontal support plates, and between the side horizontal support plates, and the two support plates in contact with these round bars are welded and connected via this round bar. A heat exchanger tube support device according to claim 2 characterized by: 4. Claim 2 or 3, characterized in that a vertical support plate is provided perpendicularly to the horizontal support plate along the flow direction of high-temperature gas to prevent resonance of the heat exchanger tube due to the gas flow. The heat exchanger tube support device described. 5. The vertical support plate is supported by inserting a support fitting with a U-shaped notch into the heat exchanger tube adjacent to the vertical support plate from the opposite side of the vertical support plate and connecting the end edge to the vertical support plate. The heat exchanger tube support device according to claim 4, characterized in that the heat exchanger tube support device is constructed as follows.