JPH0318642Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a steam turbine casing insulation device, and is an improved turbine casing insulation device that does not generate dust during installation and removal and can be reused. be. The casing heat insulation device of this invention is easy to manufacture and has a lower manufacturing cost than conventional products, making it particularly suitable for nuclear power generation turbines.

As is generally well known, the casing of a steam turbine is used covered with a thermal cover made of heat-resistant heat insulating material, and during periodic inspections of the steam turbine, the upper half and sides of the thermal insulation cover are The upper half of the turbine casing is then removed, and the turbine rotor is then lifted out of the turbine casing for inspection and repair.

In this way, when disassembling the turbine casing, it is necessary to remove the insulation cover, but the old insulation cover had a structure with a layer of clay-like refractory material applied directly to the outer surface of the turbine casing. When disassembling the casing, the upper half of the turbine casing had to be removed after destroying the upper heat insulating cover or the side heat insulating cover covering the fastening flange of the turbine casing. Therefore, after the turbine inspection, the refractory material layer of the upper thermal cover or the side thermal cover must be rebuilt, resulting in a very long turbine outage period and the cost of the refractory material for the thermal cover. Furthermore, the amount of dust generated during destruction and reconstruction of the refractory layer was undesirable.

Therefore, recently, thermal covers that have improved the above-mentioned drawbacks (for example, Utility Model Publication No. 43-31208,
(see Utility Model Publication No. 13045, etc.) came into use. In these improved heat insulation covers, a fireproof material layer that is easily destroyed and generates dust is housed in a steel heat insulation cover frame, and both sides of the fireproof material layer are covered with fireproof material, its woven fabric, wire mesh, etc. Since it is protected, there is no need to destroy the refractory material layer of the heat insulation cover when the turbine casing is disassembled, resulting in less harmful dust generation and no need to rebuild the refractory material layer.

However, the above-mentioned known improved thermal cover has the disadvantage that it is complicated in structure, requires a lot of effort to manufacture, and has a considerable cost. In particular, if the frame of the thermal cover is configured to have a complicated shape to match the irregularities of the turbine casing's external shape, the work involved in cutting, bending, and welding assemblies becomes complicated and time-consuming, which significantly increases manufacturing costs. become, again,
If the machining accuracy of a thermal cover with such a structure is low, a gap will be created between the inner surface of the thermal cover and the outer surface of the turbine casing, and air convection will occur within the gap, resulting in a significant reduction in the thermal insulation effect. The point was hot.

Therefore, the purpose of this invention is to make it easier and cheaper to manufacture than the known heat insulating cover disclosed in the above-mentioned publication, and to make it possible to quickly disassemble the turbine casing without generating dust. An object of the present invention is to provide an improved turbine casing insulation device that can be used.

The turbine casing heat insulation device according to this invention includes a frame mounted on the upper half of the turbine casing, a trapezoidal roof-shaped or trapezoidal gutter-shaped outer heat insulation cover secured to the frame, and The outer heat insulating cover includes a hollow shell made of metal and a heat insulating member in the hollow shell. It is characterized in that the space is filled with a heat insulating material made of inorganic fibers such as rock wool or glass fiber.

The hollow shells that make up the outer heat insulation cover are shells designed to have no curved parts, such as a flat plate shape, U-shape, L-shape, etc., and multiple shells can be arranged on the frame without any gaps. This results in a trapezoidal roof or trough shape that does not coincide with the generally cylindrical outer surface of the turbine casing. As described above, the hollow shell has no curved surface portion, and therefore is easy to manufacture and requires a short manufacturing time, and the manufacturing cost is considerably lower than that of the conventionally known half-cylindrical heat insulation cover. Furthermore, since the heat insulating material is sealed inside the hollow shell, no dust is generated even when the heat insulating cover is removed.

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

FIG. 1 is a cross-sectional view of a turbine casing equipped with the turbine casing device of the present invention.

In the figure, 1 is a known turbine casing that is divided into upper and lower halves, 2 is a known half-cylindrical lower heat insulation cover that covers the lower half of the turbine casing 1, and 3 is an upper part of the turbine casing 1. 4 is a trapezoidal gutter-shaped outer heat insulating cover that covers the joint flange of the half and lower halves; 4 is a trapezoidal gutter-shaped outer heat insulating cover that covers the outer surface of the upper half of the turbine casing; A blanket-shaped heat insulating member 6 is arranged to cover the turbine casing, and 6 is a frame mounted on the turbine casing.

As shown in FIG. 2, the outer heat insulation cover 4 includes an inner surface plate 4a arranged to face the outer surface of the upper half of the turbine casing, and an outer shell heat insulation cover 4 arranged parallel to the inner surface plate 4a at a predetermined interval. It has a hollow shell or a hollow frame consisting of a face plate 4b and a side plate or wall member 4c which connects the two plates 4a and 4b to form a space between the two plates, and the space in the hollow shell is filled with a hollow shell or a hollow frame. is filled with a heat insulating material 4d made of inorganic fibers such as rock wool or glass fiber. As shown in the figure, the hollow shell constituting the trapezoidal gutter-shaped outer heat insulation cover 4 has no curved portion, that is, a curved surface, and is therefore easy to design and manufacture. (For example, see Utility Model Publication No. 43-31208 and Utility Model Publication No. 58-13045.) It can be manufactured in a shorter manufacturing time and at a lower manufacturing cost, and the design can be changed for turbine casings of various diameters. It's easy to do.

As shown in the figure, the outer shell heat insulating cover 4 is secured to a frame 6 mounted in a saddle shape over the upper half of the turbine casing with buckles or the like to prevent it from moving due to vibration or the like. It is firmly supported on the turbine casing. The frame 6 may be assembled from a straight bar-shaped iron material such as an angle, but it may also be constructed from a material having heat insulating properties and vibration absorbing properties.

Upper half of turbine casing and outer heat insulation cover 4
The pillow-shaped heat insulating member 5 filled between the third
As shown in the figure, a bag-shaped outer covering 5 made of a heat-resistant inorganic fiber woven fabric such as a glass fiber woven fabric or an asbestos fiber woven fabric
a, and an inorganic fiber heat insulating material 5b filled in this jacket 5a, and is flexible and can be deformed in any way.

Since the outer shell heat insulating cover 4 is mounted on the upper half of the turbine casing via the heat insulating member 5, the heat of the turbine casing 1 is not directly transmitted to the outer shell heat retaining cover 4, and the outer shell heat retaining The amount of heat dissipated into the outside air through the cover 4 is small, and therefore, even if the hollow shell is made of metal, there is no risk that the heat insulation performance will deteriorate compared to a conventional heat insulation cover.

Note that, of course, a material having lower thermal conductivity than metal may be used as the constituent material of the hollow shell.

According to the device of the present invention having the above configuration, the following effects can be obtained.

() Since the heat insulating material in the outer heat insulation cover 4 is housed in the space within the hollow shell, no dust is generated even when the turbine casing is disassembled.

() There is no wear and tear on the outer heat insulation cover and insulation materials, and they can be reused for a long period of time.

() It is easier to design and manufacture than the conventional device, and the design can be easily changed for a turbine casing of any diameter, and it can be manufactured at a lower cost than the conventional device.

() A pillow-like heat insulating member is placed under the outer shell heat insulating cover to create no voids on the outside of the upper half of the turbine casing, resulting in a high heat retention effect. Since it does not consist of a face plate, the design can be simplified and simplified.

() There is no dust generated when the turbine casing is disassembled, and there is no wear and tear on the insulation material, etc., so the cost associated with turbine inspections and the downtime of the turbine are reduced.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a turbine casing equipped with the turbine casing heat insulation device of the present invention;
The figure is a partially cutaway perspective view of the outer heat insulation cover.
The figure is a partially cutaway perspective view of a heat insulating member disposed between an outer shell heat insulating cover and a turbine casing. 1... Turbine casing (upper half), 4...
Outer heat insulating cover, 4a...Inner plate, 4b...Outer plate, 4c...Side plate, 4d...Insulating material, 5...Insulating member, 5a...Outer cover, 5b...Insulating material.

Claims (1)

[Claims for Utility Model Registration] 1. A frame mounted on the upper half of the turbine casing, a non-curved outer heat insulation cover that is secured to the frame and covers the upper half of the turbine casing, and A turbine casing insulation device having a flexible heat insulation member disposed between a shell insulation cover and an outer surface of an upper half of the turbine casing, the outer shell insulation cover having a non-curved surface facing the upper half of the turbine casing. a shaped inner surface plate, an outer surface plate arranged parallel to the inner surface plate at a predetermined interval, and a side surface plate that connects the inner surface plate and the outer surface plate and forms a space between the two plates. A turbine casing heat insulating device comprising: a space within the outer shell heat insulating cover filled with a heat insulating material. 2. Utility model registration claim 1, characterized in that the heat insulating member is composed of a bag-shaped outer cover made of heat-resistant fibers and insulating inorganic fibers filled in the outer cover. The turbine casing insulation device described.