Fixing method for the blading of a fluid-flow machine and fixing arrangement
View Patent ↗A fixing method for blading of a fluid-flow machine, in which first of all the turbine blades ( 3 1 , 3 2 ) are inserted into the fastening slot ( 1 ) of a rotor ( 2 ) or stator until only the intermediate fitting gap is left, into which two insert elements designed as end piece halves ( 4 1 , 4 2 ) are then inserted. After that, a wedge ( 6 ) is inserted into the gap between the end piece halves ( 4 1 , 4 2 ), and the end piece halves ( 4 1 , 4 2 ) together with the wedge ( 6 ) are welded by a joining weld ( 10 ). With the method according to the invention and the arrangement according to the invention, axial forces which can warp the rotor ( 2 ) and thus cause increased rotor vibrations are advantageously avoided. The invention also relates to a fixing arrangement according to the invention.
1. A fixing method for blading of a fluid-flow machine, the method comprising:
inserting a plurality of turbine blades and intermediate pieces along a fastening slot;
providing an intermediate fitting gap between at least two of the plurality of turbine blades inserted in an adjacent position inside the fastening slot;
wherein inserting the turbine blades and intermediate pieces comprises inserting into the fastening slot until only the intermediate fitting gap for the rotor end piece is left;
inserting two insert elements comprising end piece halves into the intermediate fitting gap, the end piece halves having a width adapted to the width of the intermediate fitting gap and enclosing a gap therebetween;
inserting a wedge into the gap between the end piece halves, so that an intermediate space remains between the end piece halves above the wedge; and
welding the end piece halves together with the wedge inside the intermediate space with a joining weld.
2. The method as claimed in claim 1 , further comprising, before said welding, fitting sheet-metal shims between the fastening slot and a respective end piece half; and
removing the sheet-metal shims after said welding.
3. The method as claimed in claim 1 , comprising:
applying a buffer weld to the surfaces of the end piece halves which are oriented toward the intermediate space; and
welding the end piece halves together with the wedge inside the intermediate space at the buffer weld.
4. The method as claimed in claim 1 , wherein said turbine blades comprise moving blades fitted in a fastening slot of a rotor; or
wherein said turbine blade comprise guide blades fitted in a fastening slot of a stator.
5. The method as claimed in claim 1 , wherein said turbine blades comprise the blading of a compressor or of a turbine.
6. A fixing arrangement for blading of a fluid-flow machine, comprising:
a fastening slot;
a plurality of turbine blades and intermediate pieces inserted along the fastening slot and forming an intermediate fitting gap between at least two of the plurality of turbine blades inserted in an adjacent position inside the fastening slot;
two insert elements comprising end piece halves inserted into the intermediate fitting gap, the end piece halves having a width adapted to the width of the intermediate fitting gap and enclosing a gap between them;
a wedge inserted into the gap between the end piece halves; and
a joining weld welding the end piece halves together with the wedge above the wedge.
7. The fixing arrangement as claimed in claim 6 , further comprising:
an axial clearance between the fastening slot and a respective end piece half.
8. The fixing arrangement as claimed in claim 6 , further comprising:
a buffer weld applied between each of the end piece halves and the joining weld.
9. The fixing arrangement as claimed in claim 6 , wherein the turbine blades comprise moving blades and the fastening slot comprises a fastening slot of a rotor; or
wherein the turbine blades comprise guide blades and the fastening slot comprises a fastening slot of a stator.
10. The fixing arrangement as claimed in claim 6 , wherein the fluid-flow machine comprises a compressor or a turbine.