An impulse steam turbine equipped with assembled baffles

Abstract

The invention discloses an impulse steam turbine equipped with an assembled baffle plate, comprising a cylinder block and a baffle plate, the baffle plate includes a plurality of nozzle bodies, the side surfaces of the nozzle bodies are provided with grooves penetrating in the axial direction, and two adjacent two The grooves between the nozzle bodies form nozzles, the inner surface of the cylinder body is provided with a limit groove, the nozzle body is provided with a limit key, the limit key is embedded in the limit groove, and several nozzle bodies are arranged along the circumference The invention adopts multiple nozzle bodies to be assembled on the cylinder body in sequence to directly form the partition plate without subsequent welding process and eliminates the influence of welding on the processing accuracy of the partition plate.

Description

technical field [0001] The patent of the present invention belongs to the impulse steam turbine equipment, more specifically, it relates to an impulse steam turbine equipped with an assembled baffle. Background technique [0002] The diaphragm of the steam turbine is an important part of the steam turbine body. It and the adjacent rotor blades constitute a stage of the steam turbine, and the stage is the basic unit of the steam turbine to do work. When the high-pressure steam flows through the stationary vane cascade (nozzle) on the baffle, it will push the moving vane cascade on the rotor to rotate around the axis, thereby converting the potential energy of the steam into the mechanical energy of the rotor. [0003] The traditional impulse steam turbine diaphragm is usually two parts with upper and lower symmetry, which are respectively fixed on the upper and lower cylinder blocks. It is composed of a baffle body, a stationary blade cascade (nozzle) and the outer edge of t...

AI Technical Summary

Problems solved by technology

Although heat treatment is carried out after welding in the traditional process, the deformation of the blade caused by the welding process is difficult to recover through heat treatment

Moreover, due to the complex structure of the blade, it cannot be reshaped by finishing

This will inevitably cause this defect to exist forever

In addition, heat treatment cannot guarantee the elimination of all welding internal stress, and the residual stress may still be released after the steam turbine has been working for a period of time

Due to the uncertainty in the direction of stress release, the consequence may be that the sealing gap between the diaphragm and the rotor becomes larger, resulting in increased air leakage between stages; or the sealing gap becomes smaller, making the labyrinth on the diaphragm and rotor The seal ring rubs and becomes a safety hazard

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