JPH0874799A - Cleaning device for compressor guide blade - Google Patents

Abstract

PURPOSE: To enable guide blades to be cleaned without disassembling a compressor by ejecting high pressure liquid forward along profile surfaces following such processps as perforating groove like nozzles in areas close to the rear edges of the profile surfaces of guide blades and introducing the high pressure fluid into the nozzles so as to push and open non-welded parts of covers. CONSTITUTION: Nozzles 2d are provided like grooves in areas close to the rear edges 2c of profile surfaces 2a of guide blades 2, and covers 3 are mounted on the nozzles 2d in such a manner as to cover the nozzles 2d. The latter half part (behind the nozzle 2d) of each cover 3 is fixed to each guide blade 2 by welding, and the former half part (in front of the nozzle 2d) is stuck closely to the profile surface 2a of the guide blade 2 except during cleaning as if it is integrated with the profile surface 2a. When high pressure fluid is supplied into each nozzle 2d through each high pressure fluid introducing inlet, the front half part of the cover 3 is opened to eject high pressure fluid forward so that each profile surface 2a and front edge 2b are cleaned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device applied to guide vanes of a centrifugal compressor of a gas turbine.

[0002]

2. Description of the Related Art FIG. 7 is a sectional view of a general gas turbine. In the figure, 1 is an impeller of a centrifugal compressor, 2 is a guide vane provided at the compressor outlet, 5 is a compressor casing, 6 is a guide vane retainer, 9 is a combustor inner cylinder, and 10 is combustion. Outer cylinder, 11 is a combustion nozzle, 12 is a wall of a spiral gas passage,
Reference numeral 13 is a turbine stationary blade, and 14 is a turbine moving blade. The arrow indicates the flow of gas. The impeller 1, the guide vanes 2, the compressor casing 5, and the guide vane retainer 6 constitute a compressor.

FIG. 8 is a partial front view of a conventional guide vane. In the figure, 1 is an impeller, 2 is a guide blade, 2a is a profile surface of the guide blade, and 2b is a leading edge of the guide blade. Conventionally, there is no special device for cleaning the profile surface of the guide vanes, and the compressor is periodically disassembled and manually cleaned.

[0004]

When the centrifugal compressor is operated for a long time, the profile surface 2a of the guide blade 2 for speed reduction of the fluid to be compressed, which is located in the downstream of the impeller 1 shown in FIG.
Impurities contained in the fluid to be compressed adhere to. For example, in the case of a small centrifugal air compressor, typical deposits are Na, S and Si, and sulfate and oxide are the main components. These deposits form a laminate and reach a thickness of 2-3 mm after a long running time. As a result, in the guide vanes used in the ultra-high speed range, the performance is significantly deteriorated due to the influence of the shock wave generated from the deposit on the front edge 2b. With a single-stage compressor, the performance degradation reaches about 15-20%. Therefore, it is desirable to remove the deposits on the profile surface 2a and the front edge 2b many times to recover the performance of the compressor at all times without manually dismantling the compressor.

The present invention meets the above-mentioned demands, and it is an object of the present invention to provide a cleaning device capable of cleaning the guide vanes without disassembling the compressor.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and is a device provided in a guide blade of a centrifugal compressor, which is provided in a portion of a profile surface of the guide blade near a trailing edge. Perforated groove nozzle, made of spring steel or shape memory alloy, covering the nozzle and welded between the nozzle and the trailing edge of the guide vane, its outer surface and uncovered profile surface being smooth A cover formed to connect to the nozzle, a high-pressure fluid introduction hole provided through the compressor casing so as to connect to the nozzle at one end and to an external high-pressure fluid supply source at the other end, and to the nozzle. The present invention relates to a compressor guide vane cleaning device characterized in that, when high-pressure fluid is introduced, the high-pressure fluid pushes open an unwelded portion of the cover and ejects it forward along a profile surface.

[0007]

The high-pressure cleaning gas or liquid adheres to the profile surface by being blown out forward from the injection nozzle provided at the trailing edge of each guide vane profile along the guide vane profile while the compressor is stopped or during deceleration operation. The impurities are blown away. If the deposit is water-soluble or oil-soluble, a cleaning liquid is sprayed, and the cleaning liquid is melted and blown off. As a result, the guide vane profile surface is cleaned and the guide vane performance is restored to its initial state.

[0008]

1 is a partial front view of a guide vane according to an embodiment of the present invention. In the figure, 1 is an impeller, 2 is a guide blade, 2a is a profile surface, 2b is a leading edge, 2c is a trailing edge,
Reference numeral 2d denotes a nozzle provided in a groove shape in a portion near the rear edge of the profile surface of the guide blade, and 3 denotes a cover attached so as to cover the nozzle. 2 is an enlarged view of the vicinity of the nozzle 2d and the cover 3 of FIG. 1, and FIG. 3 is a perspective view of the same portion. The latter half of the cover 3 (behind the nozzle) is fixed to the guide blade 2 by welding W. The front half of the cover 3 (in front of the nozzle) is in close contact with the profile surface of the guide vane during normal operation (except during cleaning), and it is as if they were integrated.

FIG. 4 is a side view of the guide vanes. In the figure, 2 is a guide vane, 3 is a nozzle cover, 4 is a guide vane cover, 5 is a compressor casing, 6 is a guide vane retainer, 2d is the nozzle described above, and 7 is a guide vane cover so as to communicate with the nozzle. 4 is a high-pressure fluid introduction hole provided so as to pass through the vehicle compartment 4 and the vehicle compartment 5. The guide blade 2 and the guide blade cover 4 are integrated. The passenger compartment 5, the guide vanes 2 and the guide vane pushers 6 are connected to each other by bolts. The high pressure fluid introduction hole 7 is connected to a supply source of high pressure gas or high pressure fluid (not shown) outside the vehicle compartment. The positions of the passenger compartment 5 and the guide vane retainer 6 are also shown in FIG.

FIG. 5 is a partial front view of the guide blade when the high pressure fluid is being supplied to the nozzle 2d through the high pressure fluid introduction hole 7. FIG. 6 is a partial perspective view of the guide blade in the same state. When the high-pressure fluid is introduced into the nozzle 2d, the pressure causes the front half of the cover 3 (the front side of the nozzle) to open, and the high-pressure fluid is ejected forward from this to clean the profile surface and the front edge. Arrow 8 indicates the flow of high-pressure fluid.

The cleaning by this apparatus may be performed either when the compressor is stopped or when the compressor is operating. Assuming that the nozzle cover is designed to be cleaned while the compressor is stopped, if the gap between the cover and the profile surface when the cover is opened is approximately 2 mm, then a high pressure fluid (gas or liquid)
An injection speed of about 20 to 50 m / s can be obtained. The cleaning time is a few seconds to a few minutes. The main component of the deposit is a eutectic of Na ₂ SO ₄ , which can be dissolved in hot water at 30 ° C to 40 ° C and blown off. Further, solid deposits such as SiO are blown off by the gas pressure or water pressure of the jet.

When cleaning is performed during operation of the compressor, it is preferable to clean one or several guide vanes at one time. It is necessary to determine the number of guide vanes to be cleaned at one time so as to avoid resonance by examining the natural frequency of the impeller 1.

Spring steel or shape memory alloy is suitable for the material of the cover 3. When the cover material is spring steel, the cover comes into close contact with the profile surface due to the restoring force of the spring after cleaning. If the cover material is a shape memory alloy, after cleaning, raise the temperature of the flowing fluid so that the temperature of the cover is above the shape memory temperature, or operate with the cover open, and use the heat of compression of the gas to be compressed. Return to the initial state. The nozzle 2d can be closed by these means.

[0014]

The compressor guide vane cleaning device of the present invention comprises:
A grooved nozzle drilled in the portion of the profile surface of the guide vane near the trailing edge, made of spring steel or shape memory alloy, covering the nozzle and welded between the nozzle and the trailing edge of the guide vane A cover formed so that the outer surface thereof and the uncovered profile surface are smoothly connected, penetrating the casing of the compressor so as to connect to the nozzle at one end and to an external high-pressure fluid supply source at the other end With a high-pressure fluid introduction hole provided, when the high-pressure fluid is introduced into the nozzle, the high-pressure fluid pushes open the unwelded portion of the cover and ejects it forward along the profile surface. It is possible to clean the guide vanes without disassembling.

[Brief description of drawings]

FIG. 1 is a partial front view of a guide vane according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a portion of a nozzle and a cover shown in FIG.

FIG. 3 is a perspective view of a portion of FIG.

FIG. 4 is a side view of the guide blade of the above embodiment.

FIG. 5 is a partial front view of the guide vane when high pressure fluid is being supplied to the nozzle of the above embodiment.

FIG. 6 is a partial perspective view of the guide blade in the state of FIG.

FIG. 7 is a cross-sectional view of a general gas turbine.

FIG. 8 is a partial front view of a conventional guide vane.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Impeller 2 Guide vanes 2a Profile surface 2b Leading edge 2c Rear edge 2d Nozzle 3 Cover 4 Guide vane cover 5 Compressor casing 6 Guide vane retainer 7 High pressure fluid introduction hole 8 High pressure fluid flow 9 Combustor inner cylinder 10 Combustor outside Cylinder 11 Combustion nozzle 12 Wall of spiral gas passage 13 Turbine stationary blade 14 Turbine rotor blade W Weld

Claims (1)

[Claims] 1. A device provided on a guide vane of a centrifugal compressor, which is made of a groove nozzle, spring steel or shape memory alloy, which is bored in a portion of a profile surface of the guide vane near a trailing edge. A cover that covers the nozzle, is welded between the nozzle and the trailing edge of the guide vane, and is formed so that the outer surface of the nozzle and the uncovered profile surface are smoothly continuous, and communicate with the nozzle at one end A high-pressure fluid introduction hole is provided through the casing of the compressor so as to connect to an external high-pressure fluid supply source at the other end, and when the high-pressure fluid is introduced into the nozzle, the high-pressure fluid is welded to the cover. A device for cleaning a compressor guide blade, which pushes open a portion that is not open and ejects it forward along a profile surface.