JP2004072891A - Method and apparatus for periodical inspection on generator or motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem associated with conventional methods for periodical inspection on generators in a bus turbine-combined power plant that a gas turbine is dismantled and then a rotor is pulled out before inspection is started, therefore, a schedule for inspection on the entire power plant is prolonged. <P>SOLUTION: A temporary working floor 10 is built above one equipment (steam turbine 120) of a generator 100. Then, the generator 100 is lifted up and its rotor 102 is pulled out to the working floor to inspect the rotor and the stator. For the lift 20, a gantry crane is used. Thus, the rotor and the stator can be inspected in parallel with the overhaul of the gas turbine, and the overall inspection schedule is shortened. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and a device for periodic inspection of a generator or a motor having devices connected to both ends. More specifically, the present invention relates to a method and an apparatus for periodic inspection of a generator or the like in a single-shaft gas turbine combined power plant or the like in which, for example, a gas turbine and a steam turbine are connected back and forth.
[0002]
[Prior art]
Generally, in operation of a generator or a motor, deterioration of insulation of an internal coil (stator) and deterioration of a fixing jig (wedge) for holding the stator to an iron core occur over time. For this reason, for the purpose of maintaining stable operation of the generator or the electric motor, the internal inspection of the internal coil and the wedge is periodically performed every 4 to 10 years. In order to check the stator of the generator or the electric motor, it is necessary to open one end of the generator or the electric motor and take out the rotating body (rotor) inside.
[0003]
In a normal case, a generator or a motor has a driving device that rotates a rotary electric device such as a steam turbine or a driven device that is driven by a rotary electric device such as a fan connected to only one side. The rotor can be withdrawn on the other side of these devices. Therefore, the internal inspection can be easily performed without causing interference to the connected devices. Since the frequency of internal inspections of generators or motors is generally lower than the frequency of open inspections of connected equipment, inspection and maintenance should be performed at the same time as inspection and maintenance of connected equipment. Was completed.
[0004]
In a device of a so-called tandem arrangement having a driving device or a load device on both sides of a generator, the driving device or the load device can divide a casing into upper and lower parts, each component has a mass of at most several tens tons, and 2 Suspension devices such as overhead cranes are provided for periodic inspections every year. However, the generator or electric motor cannot be divided into upper and lower parts or the like, and has a mass of several hundred tons, for example, 200 to 300 tons, and the inspection frequency is about once every ten years. It is not economical to provide. In order to extract the rotor of the generator or the motor, the connected device is first disassembled, and the rotor of the generator or the motor is extracted in the trace of the disassembled device. As an example, in a gas turbine combined power plant in which a gas turbine and a steam turbine are connected to both ends of a generator, first, for example, the gas turbine is disassembled among the connected devices, and the upper half compartment of the gas turbine, the rotor, and the static After removing all the wing rings, the generator rotor was pulled out onto the remaining lower half cabin.
[0005]
The periodic inspection of the gas turbine combined power station is performed as follows.
[0006]
Gas turbine inspection cycle: Every two years (Electrical Utility Law, statutory)
Steam bin inspection cycle: Every 4 years (Electrical Utility Law, statutory)
Generator inspection cycle: about 10 years (not legally determined, but by each company's judgment)
[0007]
[Problems to be solved by the invention]
As described above, in the conventional periodic inspection of a generator or an electric motor having devices connected to both ends, for example, in a gas turbine power plant, after all the gas turbines are completely disassembled, the generator trace is placed on the trace of the disassembly. And the inspection is started, so that the disassembly and inspection of the gas turbine and the disassembly and inspection of the generator are a series of operation steps. That is, the generator cannot be disassembled and inspected until the disassembly of the gas turbine is completed. On the other hand, the restoration work of the gas turbine cannot be performed until the inspection and repair of the generator are completed. For this reason, there has been a problem that the regular inspection schedule of the entire power plant is prolonged.
[0008]
In addition, it is necessary to arrange a support portion for extracting the rotor of the generator in the lower casing of the gas turbine, and to provide a laying plate for temporarily placing the extracted rotor on the gas turbine compartment. Not only can these operations be performed simultaneously with the disassembly and assembly steps of the gas turbine, but also because the heavy load (rotor) is temporarily placed on the turbine casing, there is a risk of damage and deformation of the turbine structure. .
[0009]
For the purpose of avoiding such problems, the generator or the motor is divided into two parts so that the open inspection of the generator or the motor can be performed simultaneously with the connected equipment. It is also provided for each driving device or load device so that the generator or the electric motor can be independently checked periodically. However, such measures have a disadvantage that the equipment cost increases and the installation area increases, which is disadvantageous economically.
[0010]
[Means for Solving the Problems]
The present invention has been developed in view of the above-mentioned circumstances, and its technical means is to perform a periodic inspection of a generator or a motor having devices connected to both ends, and to perform periodic inspection of the generator or the motor at either end of the generator or the motor. This is a periodic inspection method for a generator or a motor, comprising constructing a temporary work floor above, extracting a rotor of the generator or the motor onto the work floor, and checking the rotor and the stator. As the generator or motor with the equipment connected at both ends, the equipment at both ends may be a turbine or a blower, and when the generator or motor is a generator, the equipment at both ends may be a gas turbine and a steam turbine. There may be. Further, in addition to the gas turbine and the steam turbine, driven equipment such as a blower and a pump may be used.
[0011]
For example, in the case of a gas turbine combined power plant, the periodic inspection of the gas turbine is every two years, the periodic inspection of the steam turbine is every four years, and the periodic inspection of the generator is every four to ten years. If a temporary work floor is constructed above the steam turbine when the periodic inspection of the steam turbine is not performed, the periodic inspection of the generator can be performed concurrently with the periodic inspection of the gas turbine.
[0012]
The apparatus of the present invention, which can suitably carry out the periodic inspection method of the present invention, comprises: a temporary work floor constructed above any of a generator having equipment connected to both ends or equipment at both ends of the motor; Alternatively, there is provided a periodic inspection device for a generator or a motor, comprising a lift-up device for lifting up the motor. At this time, if the lift-up device is a portal crane that lifts up a generator or an electric motor, the lift-up device can easily lift up using a hydraulic jack or the like while supporting a reaction force on a foundation.
[0013]
Further, the portal crane may be a portal crane in which a plurality of hydraulic jack devices are connected by beams.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
First, a general configuration example of a generator or a motor to which the present invention is applied and devices connected to both ends thereof will be described. FIG. 8 is a plan view showing an example of a device configuration of the gas turbine / steam turbine combined power plant. A gas turbine 110 is connected to one side of the generator 100, and a steam turbine 120 is connected to the other side. The gas compressed by the gas compressor driven by the steam turbine 120 is burned in a combustion chamber (not shown) by the high-pressure air compressed by the air compressor 115 to become a combustion gas, and enters the gas turbine 110 and passes through the gas turbine. Rotate. The waste gas is discharged from the exhaust stack 113. The discharged gas is introduced into a boiler (not shown), and the boiler generates steam, and the generated steam is supplied to a steam turbine 120. The gas turbine 110 and the steam turbine 120 rotate the generator 100 as a drive source, and the generator 100 generates electric power.
[0016]
At the time of periodic inspection every two years, the upper casing 112, the rotor, the exhaust casing, the casing of the air compressor 115, the rotor, the casing of the gas compressor 130, the rotor, and the like of the gas turbine 110 are disassembled and placed on the floor in the power plant. , Perform overhaul and repair. At the time of periodic inspection of the steam turbine every four years, the casing, the rotor, and the like of the steam turbine 120 are added to the above, and are disposed at appropriate positions to perform disassembly, inspection, and repair. Further, the generator 100 is regularly inspected every 4 to 10 years.
[0017]
Conventionally, the rotor 102 of the generator 100 was extracted on the gas turbine lower casing after the gas turbine 110 was disassembled, and the generator 100 was regularly inspected and repaired.
[0018]
FIGS. 9 to 12 show the steps of the periodic inspection of the conventional generator 100. FIG. FIG. 9 is a side view showing a state in which the generator 100 is lifted up by a lift device after disassembly of the gas turbine, and FIG. 10 is a front view thereof. The lift device 200 is composed of four devices mounted on rails 204 cured on both sides of the generator 100. A beam 203 crossing over the generator 100 is mounted on each of the two lift devices 202 on the left and right sides, and a wire rope 211 is suspended from the two beams 203 and connected to the trunnion 101 of the generator 100. Next, as shown in FIG. 11, the generator 100 is lifted up, and a bar made of an aluminum square is stacked under the generator 100 to perform receiving curing 103. The lift-up height is a height at which the rotor of the generator 100 can be pulled out onto the lower casing 114 of the gas turbine.
[0019]
Next, as shown in FIG. 12, the rotor 102 of the generator 100 is extracted to the side, lifted by the overhead traveling crane 220, and transported to the inspection work place. Inspect and repair the stator side and rotor side of the generator 100 respectively.
[0020]
When assembling the generator 100, the above procedure may be followed. Such an overhaul of the generator 100 cannot be started until after the gas turbine 110 is disassembled. Also, the assembly work of the gas turbine 110 could not be performed unless the assembly of the generator 100 was completed.
[0021]
The present invention enables the periodic inspection of the generator 100 to be performed in parallel irrespective of the disassembly and assembly of the gas turbine 110, and eliminates the series work to shorten the entire periodic inspection process. .
[0022]
Next, a process of the periodic inspection of the generator 100 according to the present invention will be described.
[0023]
After stopping the rotation of the steam turbine and the gas turbine, the temporary work floor 10 is assembled above the steam turbine 120 as shown in FIG. The temporary work floor 10 can be installed before starting the inspection work. The temporary work floor 10 has a structure having sufficient strength against falling of the scaffold. The temporary work floor 10 is configured such that a portion that hinders the suspension of the rotary electric device 100 and a portion that hinders disassembly of devices (eg, an exciter) that interfere with the suspension of the rotary electric device can be removed. Have an appropriate shape and structure. The temporary work floor 10 forms an upper surface of the temporary work floor at a position slightly higher than the top end of the steam turbine 120, and the rotor 102 of the generator 100 is extracted and placed on the temporary work floor 10 for inspection and repair. The part 11 above the gas compressor 130 of the temporary work floor 10 is assembled after removing the gas compressor. Also, the trunnion 101 of the generator 100 is maintained and mounted.
[0024]
A lift-up device (hydraulic portal crane) 20 for lifting up the generator 100 is installed beside the generator 100. The lift-up device 20 is composed of a jack 22 provided on a base 21 and a beam 23 extending above the left and right jacks, and suspends a suspension rope from the beam 23 and binds it to the trunnion 101 of the generator 100.
[0025]
Remove the coupling between the generator 100 and each turbine. Since the coupling has a spigot (interlocking structure), the generator 100 cannot be lifted as it is. A part (intermediate shaft) of the turbine shaft is removed, the rotor 102 of the generator 100 is moved in the axial direction, and the spigot is removed.
[0026]
The portal crane 20 lifts the generator 100 up to a height where the rotor 102 of the generator 100 can be pulled out onto the temporary work floor 10. A lift-up amount of 4 m or more is required as compared with the conventional lift-up amount of less than about 1 m shown in FIGS. In order to avoid interference with the overhead crane, the suspension beam 23 of the portal crane 20 has a low height and a sufficient bending rigidity. Alternatively, the suspension rope bound to the trunnion 101 or the like of the generator 100 is a rope made of a material such as nylon capable of reducing a bending radius, and has a configuration in which the rope length is as short as possible. For this purpose, instead of the hanging rope, a combination of a shackle and a hanging steel bar which does not need to be formed in a ring shape may be used.
[0027]
As shown in FIG. 2, the exciters, upper brackets, bearings, fan blades, end bells and the like at both ends of the rotor of the generator are disassembled.
[0028]
Next, as shown in FIG. 3, the generator 100 is lifted up, the temporary receiving frame 27 is inserted under the generator 100, and the vertical movement of the generator 100 that has been lifted is restrained. The temporary receiving frame 27 needs to be inserted under the generator 100 in a short time after the generator 100 is lifted up. When pulling out the rotor 102, the stator of the generator 100 is bound to the temporary work floor 10 to prevent the temporary receiving frame 27 from overturning. It is not necessary to be strong with the above.
[0029]
Next, as shown in FIG. 4, the lower bearing 104 of the rotor 102 is disassembled, the rotor 102 is hung by the support bracket 105, and the rotor deposit 106, the rotor receiver 107, the slide metal 108 and the like are removed. It is inserted below the rotor 102.
[0030]
Next, as shown in FIG. 5, the rotor extraction tool 30 is installed on the temporary work floor 10 and connected to the end of the rotor 102. The rotor extraction tool 30 includes a traction device 31, a wire rope 32, a sheave 33, and the like. The sheave 33 is coupled to the reaction frame 12. The rotor 102 is pulled out from the position of 102a in the direction of the arrow 35 while lifting the rotor 102 by the hanging wire 41 of the overhead crane. In the process of pulling out the rotor 102, a large overturning moment is applied to the temporary receiving frame 27 supporting the generator 100. However, the temporary work floor 10 is structured to have a strength enough to withstand this overturning moment, and the traction reaction force of the generator Was supported.
[0031]
As shown in FIG. 6, as the rotor 102 comes out, the extraction operation is continued while changing the hanging position of the hanging rope 42 of the overhead crane while moving the rotor receiver 107 and the like.
[0032]
As shown in FIG. 7, when the extraction of the rotor 102 is completed, the rotor 102 is lifted by the hanging rope 42 of the overhead crane as shown by the arrow 43, and is maintained in a state where it can be inspected and repaired. Alternatively, the rotor 102 may be transported to another work position for inspection. Inspection of the rotor is mainly appearance check, cleaning and insulation resistance test.
[0033]
The generator 100 from which the rotor 102 has been removed removes the temporary receiving frame 27 and lifts down on the foundation as shown by the arrow 26 to perform inspection and repair. After the rotor 102 is extracted, the stator of the generator 100 may be subjected to internal inspection such as insulation diagnosis while being lifted up, or may be lifted down and returned to the foundation before inspection. May go. Inspection of the stator includes inspection and replacement of the pressing force of the wedge pressing the stator coil held in the slot. When the inspection and repair of the rotor and the stator are completed, the generator 100 is assembled, returned to its original position, and centered. The assembling of the generator 100 is performed in a process reverse to the above procedure.
[0034]
According to the above embodiment, the inspection and repair of the generator 100 can be performed simultaneously in parallel without any interference with the disassembly and assembly process of the gas turbine 110. Accordingly, it has become possible to greatly reduce the entire process of the periodic inspection of the gas turbine combined power plant.
[0035]
【Example】
The present invention is applied to a periodic inspection of a single-shaft gas turbine combined power plant having a power generation output of 150 MW class composed of a gas turbine and a steam turbine. Conventionally, in addition to the 30-day regular inspection process of the gas turbine 110 alone, a 10-day regular inspection work process for the generator 100 has been added, and the entire regular inspection period required 40 days. In the present invention, the inspection of the generator 100 can be performed simultaneously with the disassembly and assembly of the gas turbine 110, and the entire periodic inspection can be completed in 30 days equivalent to the case where the internal inspection of the generator 100 is not performed. I was able to. In addition, the possibility of damage or deformation of the device caused by extracting the rotor 102 of the generator 100 onto the gas turbine 110 could be eliminated.
[0036]
In addition, when performing insulation diagnosis performed at the time of internal inspection of the generator 100, there is an effect that the evacuation distance between the energized portion and the gas turbine inspection operator can be sufficiently separated, and the operation can be performed safely.
[0037]
In the above embodiment, a gas turbine combined power plant in which a gas turbine and a steam turbine are connected at both ends has been described.However, the present invention is not limited to this.For example, a steam turbine, a blower, or the like may be provided at both ends of an electric motor. The present invention can be similarly applied to periodic inspection of an electric motor such as a connected device (an electric blower using a steam turbine as an auxiliary driving force).
[0038]
【The invention's effect】
According to the present invention, the periodic inspection of the rotary electric device can be performed without interfering with the inspection process of the device connected to the both ends in the periodic inspection of the rotary electric device having the device connected to both ends, It has become possible to simplify and shorten the periodic inspection process of the entire plant. Further, it is possible to eliminate the possibility of breakage of equipment when extracting the rotor of the rotary electric device.
[Brief description of the drawings]
FIG. 1 is a side view showing a working process of an embodiment.
FIG. 2 is a side view showing a working process of the embodiment.
FIG. 3 is a side view showing a working process of the embodiment.
FIG. 4 is a side view showing working steps of the embodiment.
FIG. 5 is a side view showing the working process of the embodiment.
FIG. 6 is a side view showing the working steps of the embodiment.
FIG. 7 is a side view showing the working process of the embodiment.
FIG. 8 is a plan view showing a device configuration and an arrangement of a gas turbine combined power plant.
FIG. 9 is a side view showing a conventional working process.
FIG. 10 is a side view showing a conventional working process.
FIG. 11 is a side view showing a conventional working process.
FIG. 12 is a side view showing a conventional working process.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Temporary work floor 11 Part (of temporary work floor) 12 Reaction frame 20 Lift-up device (portable crane)
21 Base 22 Jack 23 Beam 25, 26 Arrow 27 Temporary receiving frame 30 Extraction device 31 Traction device 32 Wire rope 33 Sheave 35 Arrow 41 Suspension wire 42 Suspension rope 43 Arrow 100 Generator 101 Trunnion 102 Rotor 103 Receiving curing 104 Bearing 105 Support Bracket 110 Gas turbine 112 Casing 113 Discharge path 114 Lower casing 115 Air compressor 120 Steam turbine 130 Gas compressor 200 Lift-up device 201 Base frame 202 Jack 203 Beam 204 Rail 211 Hanging wire 212 Shackle 213 Hanging tool 220 Overhead traveling crane

Claims (6)

In performing a periodic inspection of a generator or a motor having equipment connected to both ends, a temporary work floor is constructed above any of the equipment at both ends of the generator or the motor, and the generator or the motor is rotated on the work floor. A periodic inspection method for a generator or a motor, wherein a child is extracted and a rotor and a stator are inspected. The method of claim 1, wherein the equipment at both ends is a turbine or a blower. The generator or the electric motor according to claim 1, wherein the generator or the electric motor is a generator, the devices at both ends are a gas turbine and a steam turbine, and a temporary work floor is constructed above the steam turbine. Periodic inspection method. A generator comprising: a temporary work floor constructed above any one of a generator or a motor at both ends of which is connected to a device or a device at both ends of the motor; and a lift-up device for lifting up the generator or the motor. Or periodic inspection equipment for electric motors. 5. The periodic inspection device for a generator or a motor according to claim 4, wherein the lift-up device is a portal crane that lifts the generator or the motor. The generator or electric motor periodic inspection device according to claim 5, wherein the portal crane has a plurality of hydraulic jack devices connected by beams to form a portal.

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