SU1502854A1 - Exhaust part of axial turbine cylinder - Google Patents

Abstract

This invention relates to turbine engineering and can be used in high and medium pressure cylinders of steam turbines. The purpose of the invention is to increase the reliability of the working blades (RL) of the last stage of the cylinder. The exhaust part of the cylinder of the axial turbine contains the last stage 1, the RL 2 of the last stage 1, the additional diaphragm (DD) 3, the guide vanes (NL) 4 DD 3, the exhaust chamber (VC) 5 and the discharge pipe 6. The magnitude of the output angles NL 4 it is variable around the circumference and decreases in the direction towards the outlet nozzle, and the interblade channels formed by NL 4 are directed towards the nearest outlet nozzle. The vapor flow, the passage of the RL 2, enters the NL 4 DD 3, NL 4 turns the vapor flow in the direction of the circumferential flow into the VC 5. From the VC 5, the steam is discharged into the outlet nozzle 6. At the same time, the circumferential components of the flow rates 4, and the circumferential flow in VK 5 are close in magnitude and direction. Due to the variable output angles of the NL 4, the circumferential unevenness of the pressure drop across the X-ray laser 2 decreases, and their operation reliability increases. 2 Il.

Description

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The invention relates to turbine engineering and can be used in high and medium pressure cylinders of steam turbines.

The purpose of the invention is to increase the reliability of the working blades of the last stage of the cylinder.

FIG. 1 shows the exhaust part of the cylinder of an axial turbine, general view; in fig. 2 shows a scan of the annular section of the guide vanes of the additional diaphragm.

The exhaust part of the axial turbine cylinder contains the last stage 1, the working vanes 2 of the last stage 1, the additional diaphragm 3, the guide vanes 4 of the additional diaphragm 3, the exhaust chamber 5 the exhaust pipe 6. The guide vanes 4 form the inter-blade channels 7 of the additional diaphragm 3, 1 The sweep of the annular section of the additional diaphragm 3 has a section 8 of the location of the outlet nozzle 6. In FIG. 2 corners marked

The exit angles of the guide vanes 4 of the additional diaphragm 3. At the same time, the angles of ° C decrease towards the outlet nozzle 6, and the exit channels 7 at the exit are directed toward the nearest outlet nozzle.

The exhaust part of the cylinder of the axial turbine operates as follows.

The steam flow, the passage of the working blades 2 of the last stage 1, enters the guide vanes 4 of the additional diaphragm 3. The guide vanes 4 turn the steam flow in the direction of the transit flow in the exhaust chamber 5. From the exhaust chamber 5, the steam flow is discharged to the outlet 6. In this case, the circumferential components of the flow velocities exiting the guide vanes 4

and transit flow in the exhaust chamber 5 are close in magnitude and direction, which reduces losses when these flows are shifted.

The movement of the transit flow in the exhaust chamber 5 is associated with the presence of a variable circumferential pressure, having a minimum in sector 8 of the location of the outlet nozzle 6 and a maximum in the critical section. This variable pressure determines the variable total differential pressure of the AR to the last stage 1 and the additional diaphragm 3.

On the direction of the blades 4 of the additional diaphragm 3, a circumferentially variable differential pressure is developed due to variable angles of the output {guide vanes 4. This differential increases with decreasing angles towards the outlet nozzle 6.

LRR delta on rotor blades 2 is proportional to the difference in DR. - ARD. Due to the consistent variation of the LR and Pig around the circumference, which is ensured by the distribution of the angles, the non-uniformity of the differential РPr decreases. As a result, the decrease in the variable aerodynamic forces acting on the working vanes 2 increases with the reliability of their work.

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Claims (1)

Invention Formula The exhaust part of the axial turbine cylinder, containing the working blades of the last stage, the additional diaphragm located behind them with the formed guide vanes of the interdiscipline channels, the slope chamber with the discharge nozzles, in order to increase the reliability of the working blades of the last stage, the interscapular channels of the additional diaphragm are directed toward the nearest discharge branch pipe, and the guide vanes have exit angles that decrease as the blades approach the nearest present nozzle. Flow rates beyond the aperture diaphragm Direct transit through / until 8 camera FIG. 2