JPS60206905A - Re-heating steam turbine warm-up device - Google Patents

Abstract

PURPOSE:To enhance warmup performance of a turbine member by furnishing a plurality of warmup steam supply pipes which open inside a reheating steam turbine, and by controlling the flow control valve in each pipe in accordance with the temp. of the turbine member in the neighborhood of the opening of each pipe. CONSTITUTION:Three warmup steam supply pipes 21-23 which open inside a reheating steam turbine are installed to constitute a warmup device, wherein the supply pipe 21 is in communication with a warmup steam flow-in chamber 8 to be installed at the inner ring 3 of No.1 step nozzle diaphragm and is fixed by the use of a seal ring 9. The other supply pipes 22, 23 shall open in the neighborhood of the vane implanting part of the impeller and of the mounting part of impeller to the rotor 6. The degree of opening of a flow adjusting valve 24 in each of the supply pipes 21-23 is controlled in accordance with the output of a temp. sensor 25 which is to sense the temp. of the turbine member situated near the opening of each of the supply pipes 21-23.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a warm-up device for a reheat steam turbine used for warm-up operation of a reheat steam turbine.

[Technical Background of the Invention and Problems thereof] Recently, in steam turbine power generation plan 1-, reheat steam turbines have been frequently used in order to improve power generation efficiency.

In such reheating natural air turbines, in order to further improve power generation efficiency, there is a tendency for the main steam pressure, main steam temperature, reheat steam temperature, etc. to be adjusted.

As the temperature of reheat steam increases, thermal stress is becoming a problem in turbine parts such as the upper turbine, dynamic threshold implant, tenon part, and casing of reheat steam turbines at the time of turbine startup, into which reheat steam flows. Na Ru゛.

Furthermore, in order to increase power generation efficiency in reheat steam turbines that use reheat steam with conventional steam humidity, it is possible to reduce the startup time from turbine stop (゛) by 910 degrees, and to rapidly increase the load. Even in this case, thermal stress in turbine components such as the turbine rotor, the rotor blade implantation part, the tenon part, and the casing of the reheat steam turbine becomes a problem.

However, when the thermal stress increases during turbine startup, it causes problems with the strength of the turbine rotor, rotor blades, etc., and also causes fatigue, creep, and cracks in the turbine components, as well as damage to the casing and Problems such as deformation of the turbine rotor etc. arise.

FIG. 1 shows a conventional warm-up operation device for a reheat steam turbine. In the figure, reference numeral 1 indicates a first stage nozzle. This first stage nozzle 1 is arranged between a first stage nozzle tire phragm 2 and a first stage nozzle diaphragm inner ring 3. The first stage nozzle tire flamm 2 is fixed to the reheat turbine casing 4. And the first stage rotor blade 5
is fixed to the turbine rotor 6 via an impeller.

The figure shows a warming steam supply pipe (warming steam supply pipe 7 is installed in the first stage nozzle diaphragm inner ring 3). It communicates with the warming steam inflow chamber 8 and is fixed by a seal ring 9.

A reheat turbine steam chamber 10 is provided in the warming steam inflow chamber 8.
A plurality of A-ming steam outlet holes 11 are bored in the gap between the turbine rotor 6 and the first-stage nozzle diaphragm inner ring 3, and the A-ming steam is supplied from the A-ming steam supply pipe 7. - The steam flows out in the direction of arrow A.

However, in the reheat steam turbine warm-up device configured in this way, the temperature of the turbine members of the reheat steam turbine is controlled to be 120°C to 130'CPi! The problem is that it can only rise once in a while.

Therefore, in order to raise the temperature of the turbine components, it is necessary to increase the steam flow rate of the warming steam or to increase the pressure of the warming steam, but conventional reheat steam turbine warm-up devices do not do this in this way. There is a problem in that the turning of the reheat steam turbine becomes disconnected and the rotational speed of the turbine increases.

Accordingly, in the conventional warm-up device for a reheat steam turbine, the temperature of the turbine members of the reheat steam turbine is increased to 120°C and 13°C.
It is difficult for the temperature to rise above 0°C.
Accordingly, C, turbine All 44 at the time of turbine startup
It is Jl-1ti to suppress the thermal stress of lζ below a certain value.
I was extremely hard at work.

1.Object of the invention] The present invention has been made in response to such conventional circumstances.
It is an object of the present invention to provide a warm-up device for a reheat steam turbine that can significantly improve the warm-up temperature of turbine members compared to the conventional one without worsening thermal stress conditions.

[Summary of the Invention 1 That is, the present invention provides the following advantages: - As shown in FIG.
- a warming steam supply pipe equipped with a warming steam flow rate control valve for controlling the flow rate of warming steam for heating; and a temperature detector for detecting the temperature of each turbine member near the opening of the warming steam supply pipe. , the temperature signals from these temperature detectors are input, and the thermal stress generated in the turbine member is measured based on the temperature signals.
At the same time, this thermal stress value is compared with a preset thermal stress value and a stress difference signal is output. 'I1. ! Tahin 81 (
and a warming steam flow regulator that outputs a warming steam flow regulating valve signal that changes the opening degree of the warming steam flow regulating valve so that the thermal stress of the shrine becomes the preset thermal stress value. There is a 84°C warm-up of a reheat steam turbine, which is characterized by the following.

[Embodiment of the Invention] The details of the present invention will be described below with reference to an embodiment shown in the drawings.

FIG. 3 shows a warming steam supply pipe of an embodiment of a heating device for a reheat steam turbine according to the present invention. In this embodiment, there are three warming steam supply pipes 21, 22, 23.
opens into the reheat steam turbine.

However, one supply pipe 21 opens at the same position as the A-mink steam supply pipe shown in FIG. The diaphragm 2, the first stage nozzle IJJ, and the first stage nozzle diaphragm inner ring 3 are connected to the impeller C near the attachment point to the computer 6. Then, C1 and another supply pipe 23 are connected to the reburning turbine tarsing 4, the first stage nozzle die sepphragm 2, the first stage nozzle 1, the first stage nozzle die 17, and the noram inner ring 3 of the impeller. Each of these warming steam supply pipes 21, 22, and 23 is provided with an A-mink steam flow rate control valve 24 that opens nearby.

Further, near the openings of the A-mink steam supply pipes 21, 22, and 23, for example, thermal lightning pairs 25 are arranged, respectively. I'm still being watched.

As shown in FIG. 4, the heat of the reheat steam turbine 30 is 1r? From the burner 25, a signal indicating the temperature of the turbine member is input to a temperature detector 26. The temperature detector 26 outputs this number 1 to the thermal stress calculator 27 as a temperature signal S1. The thermal stress calculator 27 inputs the humidity signal S1 and calculates the thermal stress generated in the C turbine member based on the temperature signal S1. 1f1 and outputs a stress difference signal S2. In addition, in FIG. 4, reference numeral 31 indicates a low pressure turbine, and reference numeral 3
32 indicates a capacitor.

That is, since the thermal stress calculator 27 already knows the shape etc. of the turbine members of the reheat steam turbine,
The optimum temperature distribution of the turbine members that reduces the thermal stress at the time of starting the turbine is determined in advance, and the thermal stress value of each turbine member is set in advance based on this.

The thermal stress calculator 27 calculates the thermal stress generated in the turbine member based on the temperature signal S1, compares this value with a preset thermal stress value, and calculates the difference in thermal stress. do. This thermal stress difference is expressed as a stress difference signal S2.
output to the steam flow adjustment regulator 28.

The warming steam flow rate regulator 28 inputs the stress difference signal S2 and adjusts the thermal stress of the turbine member to a preset thermal stress value.
Warming steam flow control valves 2 each disposed in 3.
A signal S3 for controlling the opening degree of A-4 is output to the A-mink steam flow rate control valve 24.

J, that is, in the present invention, the warming steam supply pipe 21.2
Since a plurality of IJ thermal stress 1i (
f.

η゛41 In the reheating steam turbine configured as described above, the warming steam is heated to a portion where thermal stress is large at the time of turbine startup, for example, the first stage yqa.
’) Damage to the embedded part and the base of the impeller of the first stage rotor blade, etc.
And direct 18 blow (-11, J
This allows the turbine components to be heated up.

1P' (and C1, the efficiency of heat transfer to the turbine member compared to the conventional one) is always increased by 1, thereby increasing the rate of temperature rise of the turbine member, and making it possible to raise the temperature of the turbine member to a high temperature. Furthermore, since several warming steam supply pipes 21, 22, and 23 are provided, it is possible to warm up the turbine members over a wide area, and the warm-up operation time can be reduced.

[Effects of the Invention] As described above, according to the warm-up device for a thermal steam turbine of the present invention, the temperature of the turbine members of the reheat steam turbine at the time of starting the reheat steam turbine can be controlled under thermal stress conditions. It can be significantly increased compared to before without worsening. Furthermore, the warm-up operation time can be significantly shortened compared to the conventional method, making it possible to operate the reheat steam turbine efficiently.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a Qll device Cj of a conventional reheat steam turbine, and FIG. 2 is a longitudinal sectional view showing a Qll device Cj of a conventional reheat steam turbine.
1 is a block diagram without showing the device, and FIG. 3 shows the A-mink steam supply pipe of the warm-up device for the reheat steam turbine of the present invention.
The cross-sectional view, FIG. 4, shows the present invention - Warming-up of the actual redundant reheat steam turbine! ! There is an explanatory diagram showing the i position. 4・・・・・・・・・Reburn turbine casing 6
・・・・・・・・・Turbine rotor 7.21.2
2.23 Warming steam supply pipe 24...
... Warming steam flow rate control valve 25.
......Thermocouple 26...Temperature detector 27...
......Thermal stress calculator 28...
... Warming steam flow rate controller agent patent attorney rules
Kensuke Chika (and 1 other person) Picture 1

Claims (1)

[Claims] (1) Warming air flow in which opens into the reheat steam turbine and warms up the reheat steam turbine.
a warming steam supply pipe equipped with a warming steam flow control valve for controlling the heating steam flow rate, a temperature detector for detecting the temperature of the turbine member f material near the opening of these two A-warming steam supply pipes, and a temperature detector for detecting the temperature of each of the Input the temperature signal from the vessel, and based on this temperature signal, stop the heat generated in the CC Turpin Shrine, and compare this thermal stress value with a preset thermal stress value. a thermal stress calculator that outputs a stress difference signal, and a valve opening of the A-mining steam flow control valve that manually outputs the stress difference signal and determines how the thermal stress of the turbine member becomes the preset thermal stress value. 1. A warming-up device for a reheat steam turbine, comprising: a warming steam flow rate controller that outputs a warming steam flow rate control valve opening signal that changes the temperature of the warming steam flow rate.