Blade ring for an axial turbomachine, and a method for adjusting the maximum flow rate of said blade ring

Abstract

A blade ring for an axial turbomachine is provided, having an outer surface that is arranged on an outer ring and faces radially inwards, and an inner surface that is arranged on an inner ring and faces radially outwards, the surfaces being arranged concentrically and parallel to one another and delimiting an annular flow channel that tapers in the main flow direction of the axial turbomachine, as well as at least one adjustment blade that is arranged so as to be displaceable, in the flow channel, parallel to a surface line of one of the surfaces by a guiding device, and that is able to be fixed, in a predetermined position, to at least one of the rings.

1 . A blade ring for an axial turbomachine, comprising:
 an outer face which is arranged on an outer ring and is oriented radially inward, and   an inner face which is arranged on an inner ring and is oriented radially outward, which faces are arranged concentrically and parallel with one another and delimit an annular flow duct which tapers in the main flow direction of the axial turbomachine, and   at least one adjustment blade which is arranged such that it can be displaced, in the flow duct, parallel to a side line of one of the faces by a guiding device, and which can be secured in a predetermined position on at least one of the rings.   
     
     
         2 . The blade ring as claimed in  claim 1 ,
 wherein the outer face and the inner face are conical faces.   
     
     
         3 . The blade ring as claimed in  claim 1 ,
 wherein the outer face and the inner face have, in segments along the respective side line, identical radii of curvature in every cross section perpendicular to the axis of the flow duct such that, when the adjustment blade is displaced, the radial gaps between the adjustment blade and the faces remain constant.   
     
     
         4 . The blade ring as claimed in  claim 3 ,
 wherein each of the cross sections of the outer face and of the inner face is in each case formed, perpendicular to the axis of the flow duct, from a polygon or from a plurality of circle segments which are arranged immediately adjacent to one another.   
     
     
         5 . The blade ring as claimed in  claim 1 ,
 wherein the blade ring is a diagonal stage of the axial turbomachine.   
     
     
         6 . The blade ring as claimed in  claim 1 ,
 wherein the blade ring has a plurality of blades,   wherein the blades are, in alternation, the adjustment blades and blades which are securely attached to the outer face and/or to the inner face.   
     
     
         7 . The blade ring as claimed in  claim 6 ,
 wherein each of the securely attached blades is made in one piece together with the inner ring and the outer ring or in one piece together with a segment of the inner ring and a segment of the outer ring.   
     
     
         8 . The blade ring as claimed in  claim 1 ,
 wherein the guiding device has a sliding groove in the inner ring and/or in the outer ring, and a peg on the radial outer side and/or on the radial inner side of the adjustment blade, wherein the peg engages in the sliding groove.   
     
     
         9 . The blade ring as claimed in  claim 8 ,
 wherein the guiding device has, in at least one of the sliding grooves downstream in the main flow direction of the axial turbomachine, an endstop by which the adjustment blade can be secured in the predetermined position.   
     
     
         10 . The blade ring as claimed in  claim 1 ,
 wherein the guiding device is set up such that the at least one adjustment blade can be exchanged for another adjustment blade.   
     
     
         11 . An axial turbomachine having a blade ring as claimed in  claim 1 . 
     
     
         12 . The axial turbomachine as claimed in  claim 11 ,
 wherein the maximum flow rate of the axial turbomachine is defined by the maximum flow rate of the blade ring .   
     
     
         13 . A method for adjusting the maximum flow rate of a blade ring as claimed in  claim 1 , the method comprising:
 predetermining a setpoint value for the maximum flow rate of the blade ring;   determining the actual value of the maximum flow rate of the blade ring;   comparing the actual value of the maximum flow rate of the blade ring with the setpoint value for the maximum flow rate of the blade ring;   displacing the at least one adjustment blade by the guiding device parallel to the side line such that the setpoint value for the maximum flow rate is the same as the actual value of the maximum flow rate; and   securing the adjustment blade with the guiding device.