Method for preparing the rotor of a turbogenerator
OwnerKlaus Weigeltinventor
Life of this patent
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Abstract
A method of repairing the rotor showing tooth top cracking of a turbogenerator, wherein after removal of the rotor from the stator and of the existing retaining rings, the winding is protected with suitable cover materials, including sealing the whole with parafine, the entire shrink fit area is dry machined to an optimized geometry, the machined area is deburred, and after removal of the burrs and the covering and sealing material new retaining rings are fitted. The main advantage is the possibility to carry out the method on site.
Claims18
A method for repairing the rotor of a turbogenerator showing at least in part a tooth top cracking, said rotor extending into a cooperating stator and having windings lodged in a great number of axially extending rotor slots and having slot walls whereby said windings are insulated from the slot walls by slot-cells, the rotor being furthermore provided with retaining rings axially held by ring keys and containing the rotor end windings and being shrink fitted onto the rotor ends, the repairing method comprising the steps of:
- removing the rotor from the turbogenerator;
- removing the retaining rings;
- protecting the rotor windings with cover materials and tapes and sealing the rotor windings with paraffine in preparation for dry machining;
- cutting out the slot-cells in the later machining area where necessary;
- dry machining at least the shrink-fit area to be engaged by the retaining rings to eliminate all cracked portions of the teeth;
- machining grooves in the rotor for receipt of a new retaining ring locking system;
- deburring the machined areas;
- removing all burrs;
- removing the sealing material and the protection covers;
- locking the slot cells against axial movement;
- installing new end-wedges for the slots;
- installing new retaining rings dimensioned according to the optimized geometry of the rotor ends;
- and
- performing electrical tests before and after repair of the rotor.
A method for repairing the rotor of a turbogenerator showing at least in part a tooth top cracking, said rotor being arranged in a stator and having windings lodged in a great number of axially extending rotor slots each having slot walls, whereby said windings are insulated against the slot walls by slot-cells, the rotor being furthermore provided with retaining rings axially held by ring keys and containing the rotor end windings and being shrink fitted onto the rotor ends, the repair method comprising the steps of:
- removing the rotor from the turbogenerator;
- removing the rotor retaining rings;
- protecting the rotor winding with cover materials including sealing the winding with paraffine;
- dry machining the shrink fit area to be engaged by the retaining rings to remove the cracked tooth portions;
- deburring the machined area;
- removing the covering and sealing materials;
- and
- fitting new retaining rings upon the rotor.
Dependencies are inferred from the claim text.