JP3242862B2 - Heat insulation cover for turbine casing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cover for covering a casing of a steam turbine used in a power plant or the like and keeping the temperature of the casing.

[0002]

2. Description of the Related Art As shown in FIG. 6, a turbine casing 1 of a steam turbine used for rotationally driving a generator in a power plant is provided so that the turbine can be easily inspected during a periodic inspection. The upper casing 2 and the lower casing 3 having a substantially semicircular cross-sectional shape are divided into two. These upper and lower casings 2 and 3 are provided with flanges 4 and 5 protruding from their respective ends.
Are adhered to each other and tightened with bolts 6 to form an integral turbine casing.

On the other hand, the turbine casing 1 shown in FIG.
As shown in FIG. 7, the heat of the steam for rotating the turbine is completely covered by the heat insulating cover divided into the heat insulating cover 7 for the upper casing, the heat insulating cover 8 for the lower casing, and the heat insulating cover 9 for the flange that covers the flange. The heat is kept so that part of the energy is not lost to the outside world through the wall surface of the turbine casing 1.

The applicant of the present invention has previously devised a heat insulating device for a turbine casing which can be suitably used as such a heat insulating cover (Japanese Utility Model Application Publication No. 58-1304).
No. 5). According to this, as shown in FIG. 7, the heat retaining device 10 includes an expansion metal lath 12, a heat-resistant woven fabric 13, and an inorganic fiber felt 14 sequentially stretched inside a box-shaped form 11 formed by combining metal strips. At the same time, metal aggregates 15 are juxtaposed at a large pitch, and a heat-resistant woven fabric 16 is attached thereon. The heat retaining device 10 not only has a high strength, but also has a sufficient heat retaining effect while saving materials and simplifying an assembling process. Further, even if the heat insulating material is generated, dust scatters to the outside. Not to be.

[0005]

However, in the heat retaining device 10 described above, since the inorganic fiber felt 14 swells and deforms in the surface direction, the expansion metal lath 12 is adhered to the inner surface of the mold 11 so that the inorganic fiber felt 14 is fixed. The felt 14 needs to be protected. Further, since the inorganic fiber felt 14 is not fixed to the mold 11, it is necessary to cover the entire surface of the inorganic fiber felt 14 with the mold 11 and the expansion metal lath 12. Further, because of the so-called multilayer structure, there is a problem that a gap is formed between the members and the heat retaining property is reduced.
No. 0 has a problem that the structure must be complicated in order to protect the inorganic fiber felt 14.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a heat insulating cover for a turbine casing that has a simple structure and is easy to assemble, as well as heat insulating properties. It is in.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to provide a heat insulating cover for an upper casing and a lower casing which is applied to the flange of a turbine casing which is formed by connecting respective flanges of the upper casing and the lower casing. And a plurality of locking means having a substantially U-shaped side surface shape extending so as to sandwich the flange portion, and mounting fittings to the turbine casing surface and projecting at predetermined intervals toward the flange portion. A frame provided with a heat insulating material block formed by folding and laminating an inorganic fiber blanket formed by assembling inorganic fibers in a strip shape into a corrugated shape, laminating, compressing and forming a substantially rectangular parallelepiped, and burying a support bracket. And the supporting member and the locking means so that the heat retaining material block has a corrugated peak portion facing the turbine casing surface. It can be achieved by adjacent insulation cover turbine casing, characterized in that formed by locking to the frame.

In the heat insulating cover for a turbine casing according to the present invention, the inorganic fiber blanket is folded into a waveform, laminated, compressed and formed into a substantially rectangular parallelepiped shape to form a heat insulating material block, and the corrugated peaks face the turbine casing surface. As a result, the heat insulating material block does not swell and deform in a direction orthogonal to the turbine casing surface. Therefore, it is not necessary to use an expansion metal lath or the like that suppresses the bulging deformation of the heat insulating material block, so that the structure is simplified and the cost is reduced.
Also, when assembling and disassembling, it is only necessary to lock the supporting member of the heat insulating material block and the locking means of the frame or to release the locking between them, so that the maintenance work is simplified.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A heat insulating cover for a turbine casing according to the present invention will be described below in detail with reference to FIGS. Here, FIG. 1 is a schematic configuration diagram showing an embodiment of a heat insulating cover for a turbine casing according to the present invention, and FIG.
3 is a perspective view showing a heat insulating material block, FIG. 3 is a perspective view showing a frame, FIG. 4 is a cross-sectional view taken along an arrow IV in FIG. 1, and FIG. 5 is a cross-sectional perspective view showing a state where a heat insulating cover is attached to a turbine casing.

As shown in FIG. 1, a heat insulating cover 100 for a turbine casing according to the present embodiment has a plurality of heat insulating material blocks 20 attached to a frame 30 and an aluminized glass cloth 40 attached to an outer surface of the frame 30. Things.

As shown in FIG. 2, the heat insulating material block 20 is formed by folding an inorganic fiber blanket 21 made of heat-resistant inorganic fibers, such as ceramic fibers, into a strip, in a corrugated manner. And formed into a block shape by compressing so that the portions 24 extending between the ridges 22 and the valleys 23 of the corrugation are in close contact with each other. In addition, a support fitting 25 is embedded in the heat insulating material block 20. The support fitting 25 is configured by connecting a pair of strip portions 26 extending parallel to each other by a connection portion 27. Then, the plurality of portions 24 extending between the peak portions 22 and the valley portions 23 of the waveform are formed into strip portions 26.
Buried in the laminating direction of the inorganic fiber blanket 21. The connecting portion 27 has a through hole 2
8, a bolt 31 protruding from the frame 30 is inserted therethrough. As shown in FIG. 4, a through hole 29 coaxial with the through hole 28 of the support bracket 25 is provided through the heat insulating material block 20 so that a nut 32 screwed to the bolt 31 is received. Have been.

The frame 30 is, as shown in FIG.
It is formed by combining angle materials and the like, and extends vertically 33 in the figure (hereinafter referred to as a longitudinal portion).
And portions 34 and 35 that are bent in a horizontal direction and extend in parallel from the end of the longitudinal portion 33 (hereinafter, referred to as horizontal portions).
And the shape as viewed from the side is substantially U-shaped. The longitudinal portion 33 has the horizontal portions 34 and 35 in the state where the heat insulating material block 20 is attached.
Has a full length that can clamp the flange portions 4 and 5 of the first embodiment.
The width dimension of each portion 33, 34, 35 is substantially the same as or slightly larger than the width W of the heat insulating material block 20 described above. Each of the parts 33, 34.3
A plurality of (in the example in the figure, a total of seven) bolts 31 extending toward the inside of the U-shape are respectively protruded from the reinforcing members 38 and 39 disposed at the center of 5. Further, locking arms 36 and 37 for attaching the heat retaining cover 100 to the turbine casing 1 are provided on the horizontal portions 34 and 35.
Is provided.

In order to assemble the heat insulating cover 100 of the present embodiment, first, one of the heat insulating material blocks 20 is placed such that the corrugated peaks 22 (or valleys 23) are parallel to the longitudinal portions 33 of the frame 30. The longitudinal portion 33 of the frame 30
And is closely attached to the frame 30 while receiving the bolt 31 in the through hole 28 provided in the support fitting 25. Then, as shown in FIG. 4, the heat insulating material block 20 is fixed to the frame 30 by screwing and tightening the nut 32 to the bolt 31. In this manner, a total of five heat insulating material blocks 20 are sequentially attached to the longitudinal portion 33 of the frame 30. Thereafter, the heat insulating material block 20 is attached to each of the horizontal portions 34 and 35 of the frame 30 in the same procedure. The through holes 29 provided in the heat insulating material block 20 may be filled with an inorganic fiber felt when the mounting of the heat insulating material block 20 to the frame 30 is completed. Then, finally, the heat insulating cover 100 is completed by attaching the aluminum processed glass cloth 40 to the frame 30.

When the heat insulating cover 100 of the present embodiment assembled as described above is attached to the turbine casing 1, as shown in FIG. 5, the heat insulating material block 20 of the heat insulating cover 100 and the outer surface of the turbine casing 1 are connected to each other. The heat insulating futons 51 and 52 are filled in the gaps between them. The locking arms 36 and 37 provided at the upper and lower ends of the frame 30 are engaged with bolts (not shown) protruding from the outer surface of the turbine casing 1, and nuts are screwed into the bolts and tightened. Insulation cover 100
Is fixed to the turbine casing 1. According to the same procedure, the plurality of heat retaining covers 100 are fixed over the entire circumference of the turbine casing 1, and the respective heat retaining covers 100 are connected to each other via the connecting pieces 39 provided on the frame 30, and the turbine casing 1 The insulation structure is completed.

Since the heat insulating material block 20 is formed by laminating the inorganic fiber blanket 21 into a corrugated shape, the heat insulating material block 20 tends to expand and deform in the width W direction in order to return to the original shape. This means that the turbine casing 1
When connected to each other, the joint between the heat insulating covers 100 can be brought into close contact with each other, which is preferable in terms of heat insulating properties. On the other hand, since the heat insulating material block 20 is locked in shape and further by the band plate portion 26 of the support fitting 25, it does not swell and deform in the thickness T direction. Thus, in the heat retaining cover 100 of the present embodiment, it is not necessary to use an expansion metal lath or the like, because the heat retaining material block 20 is prevented from swelling and deforming toward the turbine casing 1. Therefore, the heat retaining cover 100 of the present embodiment can not only have a very simple structure, but also can complete the assembly by screwing the heat retaining material block 20 to the frame 30. Can be easily assembled. Further, in the heat insulating cover 100 of the present embodiment, since the aluminized glass cloth 40 is attached to the outer surface, it is possible to prevent the dust of the inorganic fiber blanket 21 forming the heat insulating material block 20 from scattering around. .

The heat retaining cover for a turbine casing of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications are possible based on the gist of the present invention. For example, in the above-described embodiment, the side surface shape of the frame is U-shaped in order to cover the flange portion of the turbine casing 1, but the shape of the frame is variously changed according to the shape of the portion where the heat insulating cover is attached. can do. Further, the individual shape of the heat insulating material block may be variously changed according to a portion to be attached to the frame.

[0017]

As described above, according to the heat insulating cover for a turbine casing according to the present invention, the inorganic fiber blanket is folded and laminated in a corrugated form, compressed and formed into a substantially rectangular parallelepiped shape to form a heat insulating material block, and Since the corrugated ridge is locked to the frame so as to face the turbine casing surface, the heat retaining material block does not bulge and deform in a direction orthogonal to the turbine casing surface. Therefore, it is not necessary to use an expansion metal lath or the like that suppresses the bulging deformation of the heat insulating material block, so that the structure is simplified and the cost is reduced. Also, when assembling and disassembling, it is only necessary to lock the supporting member of the heat insulating material block and the locking means of the frame or to release the locking between them, so that the maintenance work is simplified.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of a heat insulating cover for a turbine casing according to the present invention.

FIG. 2 is a perspective view showing a heat insulating material block.

FIG. 3 is a perspective view showing a frame.

FIG. 4 is a sectional view taken along arrow IV in FIG.

FIG. 5 is a sectional perspective view showing a state where the heat retaining cover shown in FIG. 4 is attached to a turbine casing.

FIG. 6 is a longitudinal sectional view of a turbine casing.

FIG. 7 is a cutaway perspective view showing a main part of a conventional heat retaining device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Turbine casing 20 Heat insulation material block 21 Inorganic fiber blanket 25 Locking fitting 30 Frame 31 Mounting bolt

Claims (1)

(57) [Claims] 1. A heat insulating cover applied to a flange portion of a turbine casing formed by connecting an upper casing and a lower casing to respective flange portions, wherein the cover extends substantially so as to sandwich the flange portion. A frame having a U-shaped side surface, a mounting bracket to the surface of the turbine casing, and a plurality of locking means protruding at predetermined intervals toward the flange portion; and a strip of inorganic fibers assembled. And a heat insulating material block formed by folding and laminating the resulting inorganic fiber blanket in a waveform, forming a substantially rectangular parallelepiped shape, and burying a support bracket, and the heat insulating material block has a corrugated crest. Are locked adjacently to the frame by the support bracket and the locking means so as to face the turbine casing surface. A heat insulating cover for a turbine casing.