JPH04209902A - Turbo shaped fluid machine - Google Patents

Abstract

PURPOSE:To maintain relative positioning relation of respective parts to normal condition so as to prevent deterioration of device performance by a method wherein a turbine casing is formed of a hub side casing and a shroud side casing, and a sealing means is interposed at the boundary part between both partition casings. CONSTITUTION:A turbine impeller 5 supported rotatably by a bearing box casing 1 is stored between an annular space 3 and an axial core part space 4 in a turbine casing 2 having an integrated structure with the bearing box casing 1 which is fixed thereto. A turbine nozzle 6 is installed on the inner wall surface of the turbine casing 2 in the vicinity of the outer circumference of the turbine impeller 5 of the space 3 side. In this case, the turbine casing 2 is formed of a hub side casing 2a and a shroud side casing 2b. A sealing means 7 is interposed at the boundary part between both partition casings 2a, 2b so as to seal the in/out sides of the casings 2a, 2b, while absorbing heat deformation of both partition casings 2a, 2b by the sealing means 7.

Description

[Detailed description of the invention]

[00011

[Field of Industrial Application] The present invention relates to a turbo-type fluid machine used, for example, for recovering high-temperature, high-pressure gas energy. [0002] Conventionally, a turbo-type fluid machine shown in FIG. 2 has been known, in which an annular space 3 in a turbine casing 12 of an integral structure fixed to a bearing box casing 1 and a space 4 in the shaft center part. In between, a turbine impeller 5 rotatably supported by the bearing box casing 1 is housed. 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 side turbine impeller 5 . For example, in the case of an expander that uses exhaust gas, high-temperature, high-pressure gas is supplied from the space 3 serving as the air supply space to the turbine impeller 5 through the turbine nozzle 6.
is rotated to recover power and send out the expanded gas to a space 4 which becomes an exhaust space. [0003]

[Problem to be solved by the invention] In the above conventional device,
The turbine casing 12 has an integral structure, and considering its thermal deformation, either the hub side or the shroud side of the turbine nozzle 6 is not fixed to the inner wall surface of the turbine casing 12 and is free to prevent damage due to thermal stress. It is necessary to keep it in good condition. Therefore, if thermal deformation occurs in the turbine casing 12 during operation of the device, a gap (
Figure 2 shows an example where a gap S occurs on the hub side.)
There is a problem in that the performance of the device deteriorates due to gas leakage from this gap. The present invention has been made to address these conventional problems, and provides a turbo fluid machine that prevents deterioration of device performance by preventing a gap from forming between a turbine casing and a turbine nozzle. This is what I am trying to do. [0004]

[Means for Solving the Problems] In order to solve the above problems, the present invention forms a turbine casing from a hub side casing and a shroud side casing, interposes a sealing means at the boundary between the two divided casings, and The turbine nozzle was fixed in close contact with the inner wall surfaces of both divided casings. [0005]

[Operation] With the above structure, thermal deformation of the casing is absorbed by elastic deformation of the sealing means and relative sliding at the boundary between the two divided casings during operation of the device.
Even if the turbine nozzle is fixed to the inner wall surfaces of both split casings to create a structure with no gaps, undue thermal stress will not be generated on the casing and the turbine nozzle, and the relative positional relationship between the turbine impeller and the turbine nozzle will be reduced. can also be maintained normally. [0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a turbo fluid machine according to the present invention, and the device shown in FIG. 2 differs from the device shown in FIG.
The mounting is substantially the same except for the front, and corresponding parts are given the same numbers and explanations will be omitted. [0007] In this device, the turbine casing 2 consists of a hub-side casing 2a and a shroud-side casing 2b, and a sealing means 7 is interposed at the boundary between the two divided casings to isolate the inside and outside of the casing, and also to separate the two divided casings from each other. The structure is such that thermal deformation is absorbed by elastic deformation of the sealing means 7 and relative sliding of the two divided casings at the boundary. In addition, the hub side casing 2
a is fixed to the bearing box casing 1, and the shroud side casing 2b is fixed to the end surface of the hub side casing 2a on the opposite side to the above-mentioned boundary part with the turbine nozzle 6 in close contact with each other. [0008] In terms of device performance, the relative positional relationship between the turbine impeller 5 and the turbine nozzle 6 is important, and a slight change in this positional relationship will lead to a decrease in performance. However, in this device, the turbine nozzle 6 is divided into two parts. It is fixed to the inner wall surface of the casing to maintain a normal positional relationship between the two. In the above embodiment, the boundary between the two divided casings is parallel to the axis of the turbine impeller 5, but the present invention is not limited to this, and the boundary does not necessarily need to be parallel to the axis. There isn't. [0009]

As is clear from the above description, according to the present invention, the turbine casing is formed from the hub side casing and the shroud side casing, and the sealing means is interposed at the boundary between the two divided casings, and the turbine nozzle It is formed by fixing it in close contact with the inner wall surface of both divided casings. Therefore, the thermal deformation of the casing is absorbed by the elastic deformation of the sealing means and the relative sliding at the boundary between the two casing segments, and the turbine nozzle is fixed to the inner wall surface of the two casing segments, creating a structure that does not create any gaps. Moreover, the casing and turbine nozzle are free from unreasonable thermal stress, and the relative positional relationship between the turbine impeller and turbine nozzle can be maintained normally, making it possible to prevent equipment performance from deteriorating. play.

[Brief explanation of the drawing]

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

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

[Explanation of symbols]

2 Turbine casing 2a Hub side casing 2b Shroud side casing 6 Turbine nozzle 7 Sealing means

Claims (1)

[Claims] Claim 1: A turbine casing is formed from a hub side casing and a shroud side casing, a sealing means is interposed at the boundary between the two divided casings, and a turbine nozzle is fixed in close contact with the inner wall surfaces of both the divided casings. A turbo-type fluid machine characterized by being formed by