Method for examining the raceway of a large roller bearing

Abstract

A method for examining the raceway of a large roller bearing in a wind turbine, in which a raceway of the large roller bearing is measured using an ultrasonic measuring unit mounted on the bearing housing, wherein the ultrasonic measuring unit detects two edges of the raceway and the relative position and/or formation thereof in relation to one another is measured.

Claims

1. A method for examining a raceway of a large roller bearing in a wind turbine, the method comprising the steps of: measuring the raceway of the large roller bearing with an ultrasonic measuring unit, wherein the measuring with the ultrasonic measuring unit includes detecting two edges of the raceway and detecting at least one of a relative position and a formation of the two edges in relation to one another, wherein the two edges include a first edge at a transition of a running surface to a lubricant groove and a second edge between an inner bearing ring and an outer bearing.

2. The method of claim 1, wherein a phased-array measuring head is used for the ultrasonic measuring unit.

3. The method of claim 1, wherein the ultrasonic measuring unit is fixedly mounted on a bearing housing.

4. The method of claim 1, wherein each of the two edges and the running surface between the two edges is measured.

5. The method of claim 1, wherein an increasing distance between the two edges is recognized as damage of at least one of said two edges.

6. The method of claim 1, wherein a widening of at least one of the two edges is recognized as a flaw.

7. The method of claim 1, wherein: the large roller bearing defines the raceway between the two edges; and, the measuring the raceway includes measuring each of the two edges and the running surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will now be described with reference to the drawings wherein:

(2) FIGS. 1A and 1B show a schematic cross-sectional view of a ball raceway having three reflection points;

(3) FIG. 2 shows the result of a check measurement for a reference edge in relation to the lubricant groove at 41; and,

(4) FIG. 3 shows the result of a reference measurement for the display of a testing edge in relation to the cage guide at 62.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

(5) FIG. 1A shows a cross section through a ball bearing having an outer bearing ring 10 and an inner bearing ring 12. The inner bearing ring 12 has a central borehole, from which lubricant (not shown) can be introduced into a lubricant groove 16. A ball 18 is provided as a roller body between the inner bearing ring 12 and the outer bearing ring 10. Various shapes and structural types of roller bodies are possible in large roller bearings. Thus, rollers, cones, and drums, with or without cage guide, can be used in the roller bearing, in addition to the balls.

(6) The region 20 shown in FIG. 1A forms a running surface for the ball 18. In the case of an externally applied ultrasonic measuring head (not shown), the regions identified with 1, 2, and 3 on the running surface 20 can be examined in particular. The transition of the edge to the lubricant groove 16 is identified by 3, the running surface is identified by 2, and the edge to the connection between the inner bearing ring 12 and the outer bearing ring 10 is identified by 1 here. A cage guide for the ball 18 can also be used here, for example.

(7) FIG. 1B shows a phased-array measuring head 22, which is aligned on a reference edge 24. The reference edge 24 is at 41, for example, and can form a reference distance for the distance measurements, the edges 28, and a region 26 of the running surface.

(8) FIG. 2 shows check measurements recorded by way of example, in which the ultrasound of the edge in relation to the lubricant groove reflected at an angle of 41 is shown. It can be seen in the illustration identified by A that the edge stands out sharply contoured.

(9) FIG. 3 shows the measurement of an edge, which is associated with a cage guide at 62: The edge is shown wider here than the edge to the lubricant groove. However, the shape and extension of the edge B indicate that it is intact.

(10) It is understood that the foregoing description is that of the preferred embodiments of the invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.

LIST OF REFERENCE NUMERALS

(11) 10 outer bearing ring 12 inner bearing ring 16 lubricant groove 18 ball 20 running surface 22 phased-array measuring head 24 reference edge 26 edge 28 edge