Method for coating a component of a turbomachine

Abstract

The present invention relates to a method for coating a component of a turbomachine in a bath, in which method, the component is partially immersed in the bath containing a coating material; the component is rotated at least intermittently around an axis of rotation, which lies outside of the bath, during the at least partial immersion; the component is at most immersed partially over and beyond the rotation.

Claims

1. A method for coating a component of a turbomachine in a bath, comprising the steps of: i) partially immersing the component in the bath containing a coating material; ii) rotating the component at least intermittently around an axis of rotation, which lies outside of the bath, during the at least partial immersion; the component having a radially inner region proximal to the axis of rotation and a radially outer region distal to the axis of rotation; iii) immersing the radially outer region of the component at most partially; and wherein the coating serves as a mask in a subsequent processing of the component and is removed after subsequent processing.

2. The method according to claim 1, wherein the component is a rotating blade ring or a segment of a rotating blade ring.

3. The method according to claim 1, wherein the component is additionally moved in step (ii) at least intermittently in a direction that lies at least partially axially.

4. The method according to claim 1, wherein the angular velocity of continued rotation of the component is changed at least intermittently.

5. The method according to claim 1, wherein the angular velocity of the rotation is constant at least intermittently.

6. The method according to claim 1, wherein, during the at least intermittent rotation, the axis of rotation is moved in a vertical direction, wherein, during the vertical movement, the component is found in an immersed state at least intermittently.

7. The method according to claim 1, wherein the axis of rotation is oriented at an oblique angle to the surface of the bath at least intermittently.

8. The method according to claim 1, wherein the component is rotated further during removal from the bath as well as after it has been removed from the bath.

9. The method according to claim 8, wherein the speed of rotation of the component is successively reduced after it has been removed from the bath as the drying progresses.

10. The method according to claim 8, wherein the coating material that drips off the component after it has been removed from the bath is returned in a liquid state to the bath.

11. The method according to claim 8, wherein the component is removed from the bath for drying.

12. The method according to claim 8, further comprising the step of: directing a stream of air onto the component from below the component; the stream of air having a velocity component that is opposite to the force of gravity.

13. The method according to claim 1, wherein the component is removed from the bath for drying following a first passage through the method steps i) to iii), wherein, afterward in a second passage in accordance with the steps i) to iii), the component is again immersed in the bath and rotated, wherein, in the first passage and in the second passage, rotation takes place in opposite directions of rotation.

14. The method according to claim 1, wherein the subsequent processing is an electrochemical method.

15. The method according to claim 1, wherein the speed of rotation of the component is successively reduced after it has been removed from the bath as the drying progresses.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) The invention will be explained in detail below on the basis of an exemplary embodiment, whereby the individual features in the scope of the dependent claims can also be a key part of the invention in other combinations and, here, too, no distinction is made in detail between the different claim categories.

(2) The present invention is shown in the accompanying figures:

(3) FIG. 1 shows a turbomachine, specifically a turbofan engine, in a longitudinal section; and

(4) FIGS. 2a, b show a coating according to the invention of a component for a turbomachine in accordance with FIG. 1.

DESCRIPTION OF THE INVENTION

(5) FIG. 1 shows a turbomachine 1, specifically a turbofan engine, in a longitudinal or axial section. The turbomachine 1 is functionally divided into a compressor 1a, a combustion chamber 1b, and a turbine 1c. Both the compressor 1a and the turbine 1c are each constructed of a plurality of stages, with each stage consisting of a guide vane ring and a rotating blade ring. During operation, rotating blade rings rotate around the longitudinal axis 3 of the turbomachine 1. In the compressor 1a, the inflow air is thereby compressed and then undergoes combustion with admixed kerosene in the downstream combustion chamber 1b. The hot gas undergoes expansion in the turbine 1c and drives the rotating blade rings. The reference number 2 refers, by way of example, to a compressor rotating blade ring in a blisk construction design.

(6) FIGS. 2a and 2b show, in schematic illustration, the coating according to the invention of a component 2, which, in this example, involves a compressor blade ring in a blisk construction design. During the coating, the component 2 is immersed in a bath 33 containing liquid lacquer as the coating material 32.

(7) During the immersion, the component 2 is rotated around an axis of rotation 22 that lies outside of the bath. The reference number 23 refers to the direction of rotation of the component 2, whereby the component 2 can be rotated constantly or can also experience intermittently an angular acceleration. In the partially immersed state, the component is rotated further; optionally, it can additionally be moved vertically upward and downward, as indicated by the reference number 24.

(8) However, the component 2 is not fully immersed over the entire circumference, not even integrated over the circumference. The ensuing, only partial coating of the component 2 with the coating material 32 is highlighted by the cross-hatched area 21, with a middle region of the component 2 remaining uncoated. Furthermore, the component 2 can additionally be moved optionally axially in the immersed state (not depicted), that is, in the present case, perpendicular to the plane of the drawing.

(9) In accordance with FIG. 2b, the component 2 was taken from the bath 33 for drying and, afterwards, it is further rotated; see the direction of rotation 23. From the blower nozzles shown, a respective stream of air 34 with a velocity component opposite to the force of gravity is directed onto the component 2. Coating material 35 that has dripped off the component 2 is collected in a drip collecting tank 37 and is returned to the bath 33 and thereby reused. As the drying progresses, it is possible to reduce the speed of rotation of the component 2 successively to a standstill.