Rotating fluid machine

Abstract

A portion at which a steam passage opens to a slide surface of a fixed side valve plate and a movable side valve plate of a rotary valve is reinforced with a reinforcing member having chipping resistance and abrasion resistance. Therefore, it can be prevented that an edge portion of the opening of the steam passage is chipped due to pulsation or the like of the pressure of high-temperature high-pressure steam supplied thereto and a resultant fragment damages the slide surface, or that abrasion dust generated from the slide surface damages the edge portion of the opening of the steam passage. Thus, the high-temperature high-pressure steam is prevented from short-cutting from the high-pressure side to the low-pressure side via the damage of the slide surface, and the supply timing of the high-temperature high-pressure steam is prevented from being upset, thus inhibiting the reduction in efficiency of an expander.

1 . A rotating fluid machine comprising: 
 a casing;    a rotor rotatably supported by the casing;    a working section provided in the rotor; and    a rotary valve provided between the casing and the rotor for controlling the supply and discharge of a working medium to and from the working section,    the rotary valve having a fixed side valve plate supported at the casing side and a movable side valve plate supported at the rotor side which are in contact with each other on a slide surface,    a working medium passage being open to the slide surface,    wherein a portion at which the working medium passage P 2  opens to the slide surface is reinforced with a reinforcing member having chipping resistance and abrasion resistance.    
   
   
       2 . The rotating fluid machine according to  claim 1 , wherein the reinforcing member formed into an annular shape is inserted into the working medium passage.  
   
   
       3 . The rotating fluid machine according to  claim 2 , wherein the reinforcing member is formed by impregnating a porous material with an abrasion-resistant material.  
   
   
       4 . The rotating fluid machine according to  claim 3 , wherein the porous material is carbon or ceramics, and the abrasion-resistant material is antimony.