REACTOR VESSEL INSPECTION DEVICE

• US 3,780,571 A
• Filed: 04/22/1971
• Issued: 12/25/1973
• Est. Priority Date: 04/22/1971
• Status: Expired due to Term

• Current Assignee: Cimcorp GCA Corporation's
• Original Assignee: Robert W. Wiesener
• Inventors: Wiesener, Robert W.
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Korkosz, Arthur E.
• Application Number:
  US05/136,411
• Time in Patent Office: 978 Days
• Field of Search: 73/67.5,67.7,67.8R,67.8S,67.9,151 95/11HC 181/.5BE 250/83.6W
• US Class Current: 376/249
• CPC Class Codes: B25J 18/025 telescopic
• CPC Class Codes: B25J 19/0004 Braking devices brakes in general F16D
• CPC Class Codes: B25J 5/00 Manipulators mounted on wheels or on carriages B25J1/00 takes precedence; programme-controlled manipulators B25J9/00 ; vehicle aspects B60, B62, e.g. remote-controlled steering for motor vehicles B62D1/24; control of position of vehicles G05D1/00
• CPC Class Codes: B25J 9/041 Cylindrical coordinate type
• CPC Class Codes: G21C 17/01 Inspection of the inner surfaces of vessels
• CPC Class Codes: G21C 19/10 Lifting devices or pulling devices adapted for co-operation with fuel elements or with control elements manipulators B25J
• CPC Class Codes: G21C 19/105 with grasping or spreading coupling elements
• CPC Class Codes: G21C 19/207 Assembling, maintenance or repair of reactor components G21C3/334 takes precedence
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

A device for in place inspecting nuclear reactor pressure vessels and which can be removed from the vessel when the vessel is in service. The device can be utilized to inspect the vessel during routine maintenance. Further, the device is mounted so that its position and movements can be repeated on subsequent inspections, and by proper recording of data from initial inspections, defects, cracks, or other hazardous situations can be discovered.

Claims

1. An assembly for inspecting a vessel having a reference axis, including mounting means, means to position said mounting means in a known relation to the reference axis of said vessel, a first movable support means mounted on said mounting means for movement in direction along the reference axis of the vessel, said first movable support means having a first end movable relative to the vessel, means to control said first movable support means for movement of said first end in direction along said axis, a second movable support means rotatably mounted to the first end of said first movable support means for rotational movement about said reference axis, said second movable support means being extendable and retractable in direction transverse to said reference axis, said second movable support means including means to mount vessel inspecting equipment thereon, sand position detection and indicating means providing signals indicating the position of the first end of said first movable support means along the reference axis with respect to a reference point, and for indicating the position of said second movable support means with respect to its rotational position about said reference axis.

2. The assembly as specified in claim 1 and manipulator arm means mounted on said second movable support means, and said manipulator arm means being actuable to adjust vessel inspection equipment mounted on said second movable support means.

3. A support assembly for an inspection device for a wall of a vessel or the like having a reference axis, said vessel being flooded with a liquid, said support assembly including mounting means, means to position said mounting means in a known relation to the reference axis of said vessel, a first support means mounted on said mounting means, means to control said support means for movement in direction along said axis, a second support means mounted to said first support means at substantially right angles to the reference axis, an inspection device mounted on said second support means, and position detection and indicating means for indicating the position of said first support means with respect to a preselected location along the reference axis of said vessel, and said second support means with respect to its position about said reference axis, and means to pressurize at least some components of the support assembly and inspection device to maintain said some components at a greater pressure than the liquid in which the components are operating, said means including a pressure regulator responsive to an input signal pressure, said regulator being mounted adjacent said second support means to sense the pressure of the liquid at said second support means, and to control said pressure in said some components at a preset relation to the sensed liquid pressure.

4. A support assembly for an inspection device for conducting inspection and tests on a wall of a chamber having a central axis, said support assembly including mounting means, means to position said mounting means in a known relation to the central axis of said chamber, a first telescoping tube means mounted on said mounting means, winch means on said mounting means to control said telescoping tube means for movement in direction along said axis, said winch means including a pair of winch drums, a separate lift cable mounted on each drum, means connecting each of said cables to said first telescoping tube means, separate brake means effective to control each of said drums to provide redundant braking for each drum, a second member rotatably mounted to said first telescoping tube means, means to rotate said second member with respect to the axis of said chamber, means to mount an inspection device on said second member, and position detection and indicating means for indicating the position of said first telescoping tube means along the axis of chamber with respect to a reference point, and to indicate the angular position of saId second member about said axis with respect to a reference position.

5. The inspection device as specified in claim 4 and means to actuate at least one of said redundant brake means whenever either of said cables has a preselected amount of slack.

6. The combination as specified in claim 4 a pair of winch gear means drivably connecting said winch drums together, and motor means driving a first of said drums, and through said gear means to a second of said drums.

7. The combination as specified in claim 6 wherein one of said separate brake means is an electric brake, and spring mounted sensing means separately anchoring first ends of each of said cables, respectively, opposite ends of said cables being attached to the respective drums, and separate switch means controlled by each of said sensing means, said sensing means actuating said switch means when the respective cable becomes slack to deenergize the drive motor for said winch drums and to actuate said one brake means.

8. A support assembly for an inspection device for conducting inspections of a chamber wall wherein the support assembly is removed between inspections, said chamber having a central axis, a first support member, means mounting said first support member accurately with respect to said central axis for movement in direction along said axis, said means mounting said first support member comprising a tripod, a plurality of stud means attached to said chamber wall adjacent the periphery of said chamber and extending substantially parallel to the central chamber axis, said tripod member including first, second and third legs, said first leg having means slidably fitting over a first of said stud means, said second leg having a first clamp assembly thereon, said first clamp assembly having jaw members, means mounting said jaw members in position to center the clamp assembly with respect to the axis of the stud means to which said first clamp assembly is attached, when the first clamp member is clamped, and said third leg having a second clamp assembly thereon, said second clamp assembly including means actuable to exert clamping force in a direction substantially perpendicular to a line between the central axes of the stud means on which said first and second clamp assemblies are mounted to center the support member with respect to the stud means, means to mount an inspection device to said first support member, and position detector and indicating means to indicate the position of said first support member and an inspection device mounted thereon relative to a reference point along said central axis.

9. A support assembly for an inspection device for a wall of a chamber such as nuclear reactor pressure vessel having a key longitudinal axis and being substantially cylindrical, comprising mounting means, a plurality of telescoping tubes mounted on said mounting means, said mounting means including means to position the longitudinal axis of the telescoping tubes substantially coinciding with the key axis of said chamber, power means to move said telescoping tubes in direction along the key longitudinal axis of said chamber, in a first path of movement, first electrical signal means to indicate the position of the telescoping tubes along said key axis with respect to a preselected position, a support member, means to rotatably mount said support member to one of the telescoping tubes for movement about the longitudinal axis of said telescoping tubes in a second path of movement, second electrical signal means to indicate the position of said support member about the axis of said telescoping tubes with respect to a reference point, and means to mount an inspection device to said support member for movement with respect to the telescoping tubes in a third path of movement different from said first and second paths of movement, and third electrical signal means to indicate movement of said means to mount said inspection device in said third path with respect to a reference point, said first, second anD third electrical signal means providing independent signals which indicate the position of an inspection device mounted on said support with respect to the wall of the chamber in the three paths of movement.

10. The combination as specified in claim 9 wherein said chamber is flooded with a liquid, and said second telescoping tube assembly comprises at least two nesting tubes, a fluid pressure actuated cylinder for operating said tubes to telescope relative to one other, said cylinder having an outer housing connected to one of said tubes, and a rod member connected to an other of said tubes, and said cylinder being filled and actuated with a liquid compatible with the liquid filling of said chamber, said cylinder having a pair of lines for control fluid, accumulator means in each of the lines for said cylinder, the output sides of said accumulators having said compatible liquid therein, a source of pneumatic pressure and control valve means for relatively pressurizing the input sides of said accumulators on input sides thereof with said pressure from said pneumatic source to in turn actuate said cylinder in the direction of lesser pressure.

11. The combination as specified in claim 10 and second valve means in each line to said cylinder for selectively closing off the fluid flow between the output sides of said accumulator means and said cylinder, said second valve means being normally biased closed, and means to open said second valve means to permit liquid to flow to and from the cylinder whenever the valve means controlling pneumatic pressure to said accumulators is actuated.

12. The combination as specified in claim 9 wherein said means to mount said inspection device for movement in said third path comprises a pivoting member movable about a pivot axis that is at substantially right angles to said key axis.

13. The combination as specified in claim 9 and an inspection device including mechanical components comprising positionable elements mounted on said means to mount an inspection device, and a manipulator arm mounted on said support assembly adjacent said inspection device, said manipulator arm being operable to adjust said positionable elements.

14. The combination of claim 9 and means to provide a readout from each of said electrical signal means at the same time an inspection signal is delivered by an inspection device mounted on said support assembly.

15. A support assembly for an inspection device for the wall of a chamber such as nuclear reactor pressure vessel having a key longitudinal axis and being substantially cylindrical, comprising mounting means, a first telescoping tube assembly, means to mount said first telescoping tube assembly to said mounting means to position the longitudinal axis of the first telescoping tube assembly substantially coinciding with said key longitudinal axis, power means to move said first telescoping tube assembly in direction along key longitudinal axis, first electrical signal means to indicate the position of the first telescoping tube assembly along said key axis with respect to a reference position, a support member, means to rotatably mount said support member to the first telescoping tube assembly for rotational movement about the longitudinal axis of said telescoping tube assembly, means to control rotational movement of said support member, second electrical signal means to indicate the position of said support member about the axis of said first telescoping tube assembly, a second telescoping tube assembly mounted on said support member in position whereby said second telescoping tube assembly has a movable end which moves in direction along an axis which is substantially perpendicular to the key longitudinal axis, means to control movement of said second telescoping tube assembly, third electrical signal means to indicate the position of said movable end of said second telescoping tube assembly relative to a reference point, means to mount an inspection device at the movable end of said second teleScoping tube assembly, said first, second and third electrical signal means providing indication of the position of the means to mount said inspection device relative to the wall of the chamber.