JP2875028B2 - Turbo type fluid machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbo-type fluid machine used for recovering high-temperature and high-pressure gas energy, for example.

[0002]

2. Description of the Related Art Conventionally, a turbo type fluid machine shown in FIG. 2 is known, and is provided between an annular space 3 and a shaft center space 4 in a turbine casing 12 of an integral structure fixed to a bearing housing 1. A turbine impeller 5 rotatably supported by the bearing housing 1 is housed therein. Furthermore, space 3
A turbine nozzle 6 is attached to the inner wall surface of the turbine casing 12 near the outer periphery of the turbine impeller 5 on the side. For example, in the case of an expander using exhaust gas, high-temperature and high-pressure gas is supplied from a space 3 serving as an air supply space to a turbine impeller 5 via a turbine nozzle 6, and the turbine impeller 5 is rotated to recover power. Then, the expanded gas is sent to the space 4 which is an exhaust space.

[0003]

In the above-mentioned conventional apparatus,
The turbine casing 12 has an integral structure. In consideration of thermal deformation, one of the hub side and the shroud side of the turbine nozzle 6 is free to be fixed to the inner wall surface of the turbine casing 12 in order to prevent breakage due to thermal stress. It is necessary to keep it in a state. For this reason, when thermal deformation occurs in the turbine casing 12 during operation of the apparatus, a gap between the turbine casing 12 and one of the inner wall surfaces (a case where a gap S is generated on the hub side in FIG. 2 is illustrated). Is caused, and there is a problem that the performance of the apparatus is reduced due to gas leakage from the gap. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described conventional problems, and provides a turbo-type fluid machine capable of preventing a reduction in device performance by preventing a gap from being formed between a turbine casing and a turbine nozzle. What you want to do.

[0004]

According to the present invention, a turbine casing is formed of a hub side casing and a shroud side casing, and a sealing means is interposed at a boundary between the two divided casings. The boundary between the divided casings was relatively slidable, and the turbine nozzle was integrally fixed and fixed to the inner wall surfaces of both divided casings.

[0005]

With the above construction, the thermal deformation of the casing is absorbed by the elastic deformation of the sealing means during operation of the apparatus and the relative sliding at the boundary between the two divided casings.
Even when the turbine nozzle is fixed to the inner wall surfaces of the two divided casings and no gap is formed, unreasonable thermal stress does not occur in the casing and the turbine nozzle, and the relative positional relationship between the turbine impeller and the turbine nozzle. Will also be able to keep normal.

[0006]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a turbo-type fluid machine according to the present invention. The apparatus shown in FIG. 2 differs from the apparatus shown in FIG.
Are substantially the same except for the method of attachment. Therefore, corresponding parts are denoted by the same reference numerals and description thereof is omitted.

In this device, the turbine casing 2 comprises a hub-side casing 2a and a shroud-side casing 2b. At the boundary between the two casings, the inside and outside of the casing are shut off with a sealing means 7 interposed therebetween. The thermal deformation is absorbed by the elastic deformation of the sealing means 7 and the relative sliding of the two divided casings at the boundary. Also, the hub side casing 2
a is fixed to the bearing box casing 1, and the shroud-side casing 2 b is fixed to the end face of the hub-side casing 2 a opposite to the boundary portion in a state of being in close contact with the turbine nozzle 6.

[0008] The relative positional relationship between the turbine impeller 5 and the turbine nozzle 6 is important in terms of the performance of the apparatus, and a slight change in this positional relation leads to a reduction in performance. It is fixed to the inner wall surface of the casing so that the positional relationship between the two can be kept normal. In the above embodiment, the boundary between the two split casings is parallel to the axis of the turbine impeller 5, but the present invention is not limited to this, and the boundary is not necessarily parallel to the axis. There is no.

[0009]

As is apparent from the above description, according to the present invention, the two-part casing is formed by forming the turbine casing from the hub-side casing and the shroud-side casing and interposing a sealing means at the boundary between the two-part casing. Are relatively slidable, and the turbine nozzle is integrally fixed and fixed to the inner wall surfaces of both split casings. For this reason, the elastic deformation of the sealing means,
Even if the turbine nozzle is fixed to the inner wall surface of the two-part casing and no gap is formed by imposing thermal deformation on the casing due to relative sliding at the boundary between the two casings, it is impossible for the casing and the turbine nozzle. Thermal stress does not occur, and the relative positional relationship between the turbine impeller and the turbine nozzle can also be maintained normally. This has the effect of preventing deterioration in device performance.

[Brief description of the drawings]

FIG. 1 is a sectional view of a turbo type fluid machine according to the present invention.

FIG. 2 is a sectional view of a conventional turbo type fluid machine.

[Explanation of symbols]

 Reference Signs List 2 turbine casing 2a hub side casing 2b shroud side casing 6 turbine nozzle 7 sealing means

Claims (1)

(57) [Claims] A turbine casing is formed of a hub-side casing and a shroud-side casing, and the boundary between the two split casings is relatively slidable with a sealing means interposed therebetween. A turbo-type fluid machine, wherein a nozzle is formed integrally with and fixed to an inner wall surface of both split casings.