SU1694937A1 - Method of protection of steam turbine against damage - Google Patents

Abstract

The invention relates to turbine construction and m. used in thermal and nuclear power plants. The aim of the invention is to increase the reliability of protection with an unacceptable increase in the moisture content of fresh steam. The method is based on continuous monitoring of the vibration state of elements of the turbine unit. The vibration of the steam supply pipelines is monitored. A vibration level signal is provided to the shut-off valve control actuator. The vibration of the steam lines of the regenerative steam extraction is monitored. When implementing the method on each line of the steam line set on three vibrodatmika. The signal from the vibration sensor is supplied to the main steam valve housing, as well as to the actuating mechanism of the control of the locking bodies, which is triggered when signals are received from at least two vibration sensors. 2 C.L.L., 1 Il. with in IW

Description

The invention relates to turbine construction, in particular, to protecting steam turbines from damage due to an increase in the moisture content of feed steam or water throwing, and can be used in thermal and nuclear power plants.

The purpose of the invention is to increase the reliability of protection with an unacceptable increase in the moisture content of fresh steam.

The drawing shows a schematic diagram of the implementation of this method.

The steam generator 1 is connected to the turbine with a fresh steam steam line 2 provided with a main steam valve 3. Through the control valve k, the steam enters the high-pressure cylinder 5 of the turbine and further into the cylinder 6

low pressure. The steam lines 7 of the regenerative outlets are connected to the cylinders 5 and 6 with the high-pressure heater 8 and with the low-pressure heater 9, respectively. On the steam lines 7 are installed check valves 10.

Vibration sensors 11 are installed on the steam line 2 of fresh steam (up to the main steam valve 3, on the valve itself and after it) and on the steam lines 7 of regenerative selections. The lines 12 of the vibration sensors 11 are connected through the amplifier 13 to the actuator} C of the stop-regulating valve.

The method is carried out as follows.

ABOUT

x

four

so oe 1

Fresh steam with a given moisture content flows from the steam generator 1 through the steam line 2 through the main steam valve 3 and the valve 4 (when they are open) to the high-pressure cylinder 5 of the turbine. The vibration level of the elements of the turbo-installation is continuously monitored by vibration sensors 11. With a constant moisture content of steam, the vibration level also does not change.

With a sharp increase in the moisture content of fresh steam (or when water is injected into the steam line 2 from the steam generator 1), the vibration level of the steam pipe 2 (especially the main steam valve body 3) sharply increases. his passing through local resistance.

This increase in the vibration level is fixed by vibration sensors 11, the signal from which via lines 12 through amplifier 13 enters the actuator. As a result, the valve 4 is closed, the steam access to the cylinder 5 of the turbine is stopped and the steam with high moisture content does not have time to get into the cylinder. Damage to the turbine assemblies does not occur.

In the event of an emergency overflow of the preheater 8 or 9 and the failure of the check valves 10, water may enter the corresponding cylinders of the turbine together with the reverse flow of steam. In order to prevent damage to the blade apparatus and the rotors, the vibration of the steam lines 7 of the regenerative selections is additionally controlled.

F

formula of invention

Claims (3)

1. A method for protecting the steam turbine from damage by controlling the vibration of turbine elements and stopping the supply of steam to the turbine from the fresh steam line when the vibration rises to an unacceptable level, in order to increase the reliability of protection during an unacceptable increase in the moisture content of the fresh steam; the control of the vibration is carried out on the steam pipeline of the fresh steam. 2. Method according to claim 2, characterized in that the control of the vibration of the fresh steam line is conducted on the main steam valve of this steam line. 3. Method 1 and 2, distinguished by the fact that, in order to increasing the reliability of protection with an unacceptable increase in the moisture content of steam in the steam pipelines of regenerative sampling, control-vibrations additionally lead on the steam pipelines of regenerative sampling.