JP3108741B2 - Water turbine runner wear measurement system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water turbine runner automatic wear measuring device capable of continuously measuring the gap between the water turbine runner and the lower cover even during operation of the water turbine runner and automatically measuring and monitoring the wear of the water turbine runner. Things.

[0002]

2. Description of the Related Art Since the runner of a water turbine is constantly rotating in flowing water, it has been impossible to measure the wear amount of the runner from outside. For this reason, in order to measure the wear amount of the turbine runner, stop the main engine, drain the water in the suction pipe liner, assemble the scaffold, measure the wear amount of the runner, disassemble the scaffold in the suction pipe liner, It is necessary to take steps to restart operation. Therefore, the gap was measured while the main engine was stopped for several hours. However, in a power plant where it was difficult to stop the main engine, it was impossible or extremely difficult to determine the degree of wear of the water turbine runner.

[0003]

However, the runner of the water turbine is gradually worn by running water and soil and the like in the running water. As the wear progresses, the gap between the runner and the lower cover increases, and when the gap increases, performance decreases due to an increase in water thrust load and an increase in water leakage loss around the runner, or There was a problem that vibration increased.

The present invention has been made in view of the above problems, and in order to eliminate the above problems, it is possible to constantly measure and monitor the gap between the runner and the lower cover during rotation of the turbine runner, and to replace the liner. It is an object of the present invention to provide a water turbine runner wear amount automatic measuring device capable of predicting a timing and an inspection timing of a runner and a runner attached to a lower cover.

[0005]

According to the present invention, as shown in FIGS. 1 and 2, a gap between a water turbine runner (3) and a lower cover (5) is measured in a non-contact manner. Gap sensor (1-1 to 1-4, 1-5 to 1-8)
Are provided on the inner periphery of the lower cover (5), and an average gap calculating means (converters 2-1 to 2-4, 2-7 to 2-10, calculating Unit 2-5) and display means (2-6) for displaying the average gap value calculated by the average gap calculation means, and the turbine runner (3) and the lower cover ( 5)
The average gap value of the gap between them is displayed on the display means.

[0006]

According to the present invention, the gap between the turbine runner and the lower cover (5) is measured by a plurality of gap sensors in a non-contact manner and the output signal is output to the average gap calculating means. The average gap calculating means constantly calculates the average gap value between the turbine wheel liner and the lower cover from the output signal of the gap sensor, sends it to the display means, and displays the average gap value. From the displayed average gap value, the degree of wear of the runner can be known, and the replacement time of the liner and the inspection time of the runner can be predicted to make an appropriate maintenance plan.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a configuration example of a water turbine runner wear amount automatic measuring device of the present invention. As shown in the figure, the automatic turbine runner abrasion amount measuring apparatus includes a gap sensor 1-1.
1-4 and gap sensors 1-5-1-8 (see FIG. 2)
And an automatic measurement unit 2. The automatic measuring unit 2 includes converters 2-1 to 2-4, converter 2-
7 to 2-10, an operation unit 2-5, and a display unit 2-6. Each of the converters 2-1 to 2-4 has a lower cover.
5, gap sensors 1-1 to 1-4 embedded in the upper part
, And the output signals of the gap sensors 1-5 to 1-8 embedded in the lower part of the lower cover 5 are input to each of the converters 2-7 to 2-10.

FIG. 2 is a view showing a mounting position of a gap sensor of the automatic measuring device. As shown in the figure, the amount of water flowing from the water inlet 10 to the suction pipe 11 is adjusted by the guide vanes 8 and drives the runner 3 to rotate the main shaft 6.
A generator (not shown) connected thereto is driven to generate power. Reference numeral 7 denotes a main bearing.

The basic principle of the gap sensor used in this embodiment is that a high-frequency coil is used for the probe,
When the conductor or the magnetic body approaches the magnetic field of the coil, the eddy current generated in the conductor or the change in the magnetic conductivity due to the magnetic body changes the inductance of the probe coil and the change in Q. By appropriately selecting the shape of the probe coil, static change without contact and
Dynamic changes can be measured.

A description will be given with reference to FIG. In consideration of wear, the gap sensors 1-1 to 1-4 are provided with a measurement hole s in the upper liner 4a of the lower cover 5 and installed on the flowing water surface. Embedded in Similarly, a gap sensor is attached to the lower liner 4b (see FIG. 2) of the lower cover 5 in exactly the same manner. This is provided because the change in the gap is different between the upper part and the lower part of the runner.

The gap sensors 1-1 to 1-4 are runners 3
A between the front end of the lower cover 5 and the upper liner 4a of the lower cover 5
To d, and the detected signals are respectively converted by the converters 2-1.
The signal is converted by .about.2-4 and input to the arithmetic unit 2-5.
The arithmetic unit 2-5 calculates an average value of each signal and displays the average value on the display unit 2-5. Similarly, the gap sensor 1-5 to 1-8 attached to the lower liner 4b of the lower cover 5 detects the tip of the runner 3 and the gap between the lower liner 4b of the lower cover 5 and the converter 2-7. ２−2-10, the signal is converted, and input to the arithmetic unit 2-5. The arithmetic unit 2-5 calculates the average value of each signal and displays the average value on the display unit 2-5.

Therefore, the display section 2-5 has an average value of the gaps a, b, c, and d between the tip of the runner 3 and the upper liner 4a, and a gap between the tip of the runner 3 and the lower liner 4b of the lower cover 5. Are displayed alternately, and the maintenance person monitors the average value of the gap displayed on the display section 2-5, predicts the replacement time of the liner and the inspection time of the runner 3, and makes an appropriate maintenance plan. I can do it. Since there is a considerable difference between the wear on the upper liner 4a side and the wear on the lower liner 4b side, it is preferable to alternate the display as described above.

In the above embodiment, the lower cover 5 has
Although four gap sensors are provided at the bottom and at the bottom, the number is not limited to four and may be any number as long as the average value can be calculated. The gap sensor may also be a non-contact type detecting means, and is not limited to a sensor using a high frequency coil.

In the above embodiment, an example is shown in which the gap between the tip of the runner 3 and the upper liner 4a of the lower cover 5 and the gap between the tip of the runner 3 and the lower liner 4b of the lower cover 5 are measured. However, the present invention is not limited to this, and the gap between the tip of the runner 3 and the lower cover 5 may be measured.

[0015]

As described above, according to the present invention, the following excellent effects are expected. The gap between the turbine runner and the lower cover is constantly measured in a non-contact manner with a plurality of gap sensors, and the average gap value is calculated by the average gap calculation means and used as display means, so maintenance personnel monitor the display. The replacement time of the liner and the inspection time of the runner can be predicted and an appropriate maintenance plan can be made.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration example of an apparatus for automatically measuring the amount of wear of a water turbine runner according to the present invention.

FIG. 2 is a view showing a mounting position of a gap sensor of the present measuring device.

[Explanation of symbols]

 1-1 Gap sensor 1-2 Gap sensor 1-3 Gap sensor 1-4 Gap sensor 1-5 Gap sensor 1-6 Gap sensor 1-7 Gap sensor 1-8 Gap sensor 2 Measuring device 2-1 Converter 2- 2 converter 2-3 converter 2-4 converter 2-5 operation unit 2-6 display unit 2-7 converter 2-8 converter 2-9 converter 2-10 converter 3 runner 4a upper liner 4b lower Liner 5 Lower cover 6 Main shaft 7 Main bearing 8 Guide vane 9 Upper cover 10 Inlet 11 Suction pipe

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G01B 21/00-21/32 G01B 11/00-11/30 102 F03B 1/00-11/08

Claims (1)

(57) [Claims] A plurality of gap sensors for measuring a gap between a turbine runner and a lower cover in a non-contact manner are provided on an inner periphery of the lower cover, and an average gap is calculated from an output signal of the gap sensor. Means, and means for displaying the average gap value calculated by the average gap calculation means, wherein the average gap value of the gap between the turbine runner and the lower cover is displayed on the display means during operation of the turbine runner. Automatic measuring device for the amount of wear of a water turbine runner.