JPH0439393Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a gas turbine, and more particularly to a gas turbine with a combustor that projects substantially in the radial direction.

[Conventional technology]

Conventionally, there is a gas turbine shown in FIG. 4 (see Japanese Utility Model Application No. 54-69205). In this diagram,
50 is a centrifugal compressor; 51 is a combustor;
The combustion gas G from is guided in the circumferential direction inside the scroll 52, and is directed to the stator blades and rotor blades 61, 62, 63, 64, 65, of the first to third stages of the turbine.
66. Therefore, each wing 61...6
6. Scroll 52 and nozzle support 67
are exposed to high temperature and high pressure atmospheres and may require inspection.

Next, the inspection method will be explained.

First, the combustor 51 is removed from the main housing 53, and the scroll 52 is visually inspected. Next, from the exhaust differential user 54 provided on the downstream side A of the main housing 53 in the axial direction,
Remove the duct 55. After these are removed, each wing 61, 62, 65, 6 is inspected using an inspection instrument (hereinafter referred to as a borescope) that has a lens at the tip of a long and thin tube and can be twisted and inserted into a narrow space.
Inspect 6. In other words, the first stage static rotor blades 61, 6
Regarding No. 2, a borescope is inserted from inside the scroll 52 in the direction of arrow C and inspected. On the other hand, the third stage static rotor blades 65 and 66 are inspected by inserting a borescope in the direction of arrow D.

[The problem that the idea aims to solve]

However, in the above-mentioned conventional technology, it is necessary to remove the large combustor 51 during inspection, which takes time.

Furthermore, as mentioned above, the first and third stage static rotor blades 61, 62, 65, and 66 can be inspected using a borescope, but the second stage static rotor blades 63 and 64 cannot be inspected. , Since the shape of each wing 61...66 is complicated, a borescope cannot be inserted into the engine, which poses the problem that inspection cannot be performed while the engine is still assembled. Furthermore, since the rear end portion 62a of the first stage rotor blade 62 has a thin wall thickness, special inspection is required. As shown in C, since a borescope is inserted, it is difficult to fit the borescope to the rear end portion 62a. Therefore, even when the static rotor blade is a two-stage type, inspection of the rear end portion 62a is difficult. There was a problem that it was not always possible to do it adequately. In other words, there were parts that could not be inspected using a borescope, and therefore there was a problem in that sufficient inspection could not be carried out.

This invention was made in view of the above-mentioned conventional problems, and aims to provide a gas turbine that can shorten the inspection time and allow sufficient inspection.

[Means to solve the problem]

In order to achieve the above purpose, this invention first reduces the length of the scroll in the axial direction as it goes downstream in the circumferential direction, and inspects the scroll at the position where the length of the scroll is reduced in the main housing. A hole is provided. Furthermore, an insertion hole into which an inspection instrument such as a borescope is inserted is provided at a position corresponding to the inspection hole in the nozzle support. The inspection hole and the insertion hole are respectively provided with a lid body and a cap for closing them.

[Effect]

According to this invention, since an inspection hole is provided in the main housing, inspection can be performed by removing the small lid without removing the large combustor.

Further, the insertion hole into which the borescope is inserted can be provided at a position where it is easy to inspect the static rotor blade using the borescope, so that sufficient inspection is possible.

〔Example〕

An embodiment of this invention will be described below with reference to the drawings.

In FIG. 1, 1 is a speed reducer, which is fixed to a base (not shown). An intermediate housing 3 is connected to this reduction gear 1 via a frame-shaped inlet housing 2. First and second centrifugal compressors 4 and 5 are housed in the inlet housing 2 and intermediate housing 3, respectively. A main housing 7 is fixed to the intermediate housing 3.

Reference numeral 6 denotes a combustor, which is located on the downstream side A of the second centrifugal compressor 5 in the axial direction, and is provided so as to protrude substantially in the radial direction of the main housing 7, as shown in FIG. A scroll 8 and a turbine 9 are attached to the main housing 7, as shown in FIG.

The scroll 8 guides the combustion gas G from the combustor 6 to the turbine 9 in FIG. 1 while swirling it in the circumferential direction B in FIG. 2, and is on the downstream side in the circumferential direction B in FIG. 1, the length in the axial direction A becomes narrower as shown by the dashed line in FIG. The scroll 8 in the main housing 7
An inspection hole 10 shown in FIG. 3 is provided at the position where the length is narrowed. This inspection hole 10 is closed by a lid 12 fastened to the main housing 7 with bolts 11. In addition, the lid body 12
A seal member (not shown) is inserted between the main housing 7 and the main housing 7 .

Reference numeral 13 denotes a nozzle support, which is formed into a cylindrical shape as a whole, and is attached to the stator blades 6 of the first to third stages of the turbine 9.
1, 63, and 65. An insertion hole 14 into which a borescope (not shown) is inserted is bored in the nozzle support 13 at a position corresponding to the inspection hole 10. This insertion hole 14
corresponds to the position of the second stator vane 63 in this embodiment. A female thread is formed in the insertion hole 14, and a bolt cap 15 is screwed into the insertion hole 14, thereby closing the insertion hole 14.
Note that the other configurations are the same as those of the conventional example shown in FIG. 4, and the same or corresponding parts are denoted by the same reference numerals and detailed explanation thereof will be omitted.

Next, the inspection method will be explained.

First, the flange 12 and duct 55 are removed, and the scroll 8, nozzle support 13, joints thereof, etc. are visually inspected through the inspection hole 10. Next, remove the bolt cap 15,
A borescope (not shown) is inserted into the insertion hole 14 from the inspection hole 10, and thereby the second stage stator blade 6
3. Inspect the first-stage rotor blades 62, the first-stage stationary blades 61, and the second-stage rotor blades 64. On the other hand, the stator blades 65 and rotor blades 66 of the third stage are the same as before.
Insert the borescope as shown by arrow D and inspect.

In the above configuration, this invention provides an inspection hole 10 in the main housing 7, so that the small lid body 1
Inspection can be performed by removing 2 and bolt cap 15. That is, there is no need to remove the large combustor 6 (FIG. 1). Therefore, inspection time can be shortened.

Here, in this invention, the axial direction A of the scroll 8 is
The length is narrowed toward the downstream side in the circumferential direction B in FIG. 2, and an inspection hole 10 is provided at this narrowed position as shown in FIG. 3. Therefore, since the scroll 8 does not get in the way, visual inspection can be performed through the inspection hole 10, and a borescope can be inserted.

In addition, the insertion hole 14 into which the borescope is inserted is
Since it is provided at a position corresponding to the second-stage stator vane 63, from here, the first-stage and second-stage movable and stator vanes 61...64 are inspected.
2 can be inspected using a borescope. Of course, the insertion hole 14 does not necessarily need to be provided at the position of this embodiment, but may be provided at a position where inspection using a borescope is easy.

In this embodiment, one inspection hole 10 and one insertion hole 14 are provided, but a plurality of these may be provided, for example, a plurality of insertion holes 14 may be provided in the axial direction A. Further, in this embodiment, the inspection hole 10 is provided at the most downstream side in the circumferential direction B as shown in FIG. Any position narrowed in the axial direction A is sufficient.

[Effect of idea]

As explained above, according to this invention, since the inspection hole and the insertion hole are provided corresponding to the narrowed position of the scroll, the inspection time can be shortened and a sufficient inspection can be performed.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a gas turbine showing an embodiment of this invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 2, and Fig. 4 is a conventional sectional view. It is a sectional view showing an example. 6...Combustor, 7...Main housing, 8...
...Scroll, 9...Turbine, 10...Inspection hole, 12...Lid, 13...Nozzle support, 1
4...Insertion hole, 15...(Bolt) cap, A
...Axial direction, B...Downstream in the circumferential direction, G...Combustion gas.

Claims (1)

[Scope of utility model registration request] A combustor that protrudes approximately in the radial direction of a gas turbine, a scroll that guides combustion gas from the combustor to the turbine, and whose length is narrowed in the axial direction as it goes downstream in the circumferential direction;
A main housing in which a combustor and a turbine are installed, an inspection hole provided in the main housing at a position where the length of the scroll is narrowed, a lid body that closes this inspection hole, and a lid body provided in the main housing. A nozzle support provided to support the stationary blade of the turbine, an insertion hole provided in the nozzle support at a position corresponding to the inspection hole, into which an inspection instrument is inserted, and a cap that closes the insertion hole. gas turbine.