DEVICE AND METHOD FOR OPERATING IN A WATER CHAMBER OF A HEAT EXCHANGER

Abstract

The invention relates to a device (10) for operating in a water chamber (7) of a heat exchanger (1) comprising a wall (6) of substantially hemispherical shape and, at its upper portion, a tube plate (5) traversed by a plurality of vertical holes (4). The device comprises at least one rail (11) furnished with members for attachment on the bottom face of the tube plate (5) and supporting at least one trolley (15) that can be moved along the said rail (11) and fitted with a pendular lifting means (19) and a robotic arm (20) comprising an attachment base (30) furnished with members for coupling on the bottom face of the tube plate (5) and a drive means interacting with the lifting means (19) to draw the attachment base (30) against the tube plate (5).

Description

The invention will be better understood on reading the following description, given as an example and made with reference to the appended drawings, in which:

FIG. 1 is a schematic view, in perspective partially cut away, of the lower portion of a steam generator comprising a water chamber in which an operation is carried out by means of a device according to the invention,

FIG. 2 is a schematic view in perspective of a ramp for inserting a robotic arm of the operating device,

FIG. 3 is a schematic view in perspective of a rail and of a trolley for supporting and moving the robotic arm,

FIG. 4 is a schematic view in cross section of the rail and the trolley of FIG. 3,

FIG. 5 is a schematic view in perspective of a base for attachment of the robotic arm to the tube plate,

FIG. 6 is a schematic view in perspective of an example of a tool-carrier for the robotic arm, and

FIG. 7 is a partial schematic view in perspective of the steam generator water chamber fitted with the operating device according to the invention.

Claims

1. Device for operating in a water chamber of a heat exchanger comprising a wall of substantially hemispherical shape comprising at least one entry hatch and delimited at its upper portion by a tube plate traversed by a plurality of vertical holes, wherein it comprises: at least one rail furnished with members for attachment on the bottom face of the tube plate Rand supporting at least one trolley that can be moved along the said rail and fitted with a pendular lifting means, anda robotic arm comprising an attachment base furnished, on the one hand, with members for coupling on the bottom face of the tube plate either side of the said rail and, on the other hand, with a drive means interacting with the lifting means to draw the attachment base against the tube plate.

2. Device according to claim 1, wherein the said at least one rail comprises at least one second rail placed in the extension of the first rail and one second trolley that can be moved along the rail, and in that the device comprises a tool-carrier comprising an attachment base furnished, on the one hand, with members for coupling on the bottom face of the tube plate, either side of the said rail, and, on the other hand, a drive means interacting with the lifting means to draw the attachment base against the tube plate.

3. Device according to claim 1 wherein the said attachment members of the said at least one rail are formed by at least two retaining clamps each intended to be inserted into a vertical hole of the tube plate

4. Device according to claim 1 wherein it comprises a movable ramp for inserting the robotic arm comprising elements for attachment on the outer periphery of the entry hatch and a plate for supporting the robotic arm whose attachment base is placed facing the entry hatch and can be moved on the said ramp.

5. Device according to claim 1 wherein the attachment base of the robotic arm and of the tool-carrier is formed by a bearing plate of generally parallelepipedic shape comprising a central housing of the drive means and, on two opposite sides, a recess for positioning the rail.

6. Device according to claim 5, wherein the bearing plate comprises, in at least one recess of one of its sides, two indexing posts each intended to be inserted into a hole of the soleplate in correspondence with a vertical hole of the tube plate.

7. Device according to claim 1 wherein the coupling members of the bearing plate comprise at least two hydraulic retaining clamps each intended to be inserted into a vertical hole of the tube plate.

8. Device according to claim 1 wherein the coupling members of the bearing plate comprise four hydraulic retaining clamps each intended to be inserted into a vertical hole of the tube plate, each of the said clamps being placed on a corner of the bearing plate.

9. Device according to claim 1 wherein the pendular lifting means is formed by a chain or a cable.

10. Device according to claim 1 wherein the drive means is formed by a wheel rotated by a reducing gear and furnished with members for engagement with the lifting means.

11. Device according to claim 10, wherein the wheel is a gear wheel.

12. Method of operating in a water chamber of a heat exchanger comprising a wall of substantially hemispherical shape comprising at least one entry hatch and delimited at its upper portion by a tube plate traversed by a plurality of vertical holes, wherein: at least one rail supporting at least one trolley that can be moved along the said rail and is fitted with a pendular lifting means is inserted through the entry hatch into the water chamber,the said rail is attached on the bottom face of the tube plate,outside the water chamber, a robotic arm is placed comprising an attachment base furnished, on the one hand, with members for coupling on the bottom face of the tube plate and either side of the said rail and, on the other hand, with a drive means interacting with the lifting meansthe attachment base of the robotic arm is placed facing the entry hatch,the robotic arm is hoisted inside the water chamber by means of the lifting means interacting with the drive means,the attachment base of the robotic arm is attached in a determined position on the bottom face of the tube plate by the members for coupling in the vertical holes, andthe robotic arm is controlled remotely from outside the water chamber to carry out the various operations inside this water chamber.

13. Method according to claim 12, wherein, on the one hand, by the action of the drive means interacting with the lifting means and, on the other hand, by means of the trolley, the robotic arm is moved to a new predetermined position to carry out a new series of operations inside the water chamber.

14. Method according to claim 12 wherein, after the attachment base of the robotic arm has been attached on the bottom face of the tube plate: facing the entry hatch, an attachment base of a tool-carrier is placed furnished with members for coupling on the bottom face of the tube plated either side of the said rail and of a drive means interacting with the lifting meansthe tool-carrier is hoisted inside the water chamber by means of the lifting means interacting with the drive means,in a determined position, the attachment base of the tool-carrier is attached on the bottom face of the tube plate by the coupling members in the vertical holes, andthe robotic arm is controlled remotely from the outside of the water chamber to carry out, on the one hand, various operations inside this water chamber and, on the other hand, tool-changes necessary to complete the operation, by causing the end of the robotic arm to interact with the tools waiting on the tool-carrier.