Method and device for securing a threaded element screwed into a threaded seat, method for mounting at least one balancing weight of a turbine, and a turbine

A method for installing at least one balancing weight of a turbine or a steam turbine, the method comprising:

• immobilizing the at least one balancing weight by means of a threaded element configured as a mounting screw,
• during a final balancing process carried out under operational conditions, tightening the threaded element with a defined torque in a threaded balancing weight seat,
• at least partially plastically deforming at least the threaded element screwed into the threaded balancing weight seat by deforming means of a tool such that it is then arranged in a rotationally secure manner in the threaded balancing weight seat,
• placing the tool axially in front of the threaded element, in that a guide element of the tool is plugged axially into a drive recess of the threaded element, and
• accelerating the deforming means placed thus axially in front of the threaded element in the direction of the threaded element,
• moving the deforming means relative to the guide element plugged into the drive recess such that at least the first thread turn, oriented toward the tool, of the threaded element and/or of the threaded balancing weight seat is deformed by the deforming means in order to secure the threaded element in the threaded balancing weight seat.

A turbine or a steam turbine, having

• at least one rotor that rotates and holds turbine blades, and having balancing weights for balancing the rotating rotor,
• wherein the balancing weights are immobilized by means of a mounting screw configured as a threaded element, and
• wherein the threaded element is secured in its threaded balancing weight seat using a captive retainer, wherein the captive retainer is created by a plastic deformation of the threaded element and/or of the threaded balancing weight seat,
• wherein only a first turn of the thread of the threaded element and/or of the threaded balancing weight seat is plastically deformed, such that the threaded element can once again be unscrewed from its threaded balancing weight seat in order to be able to move or remove the balancing weight.