Abstract: There is disclosed a remotely deployed and operated boiling water reactor camera inspection arm. In an embodiment, the remotely deployed and operated boiling water reactor camera inspection arm has a vertical actuator, that includes a bi-stable lightweight reelable tube configurable from a rolled retracted state to an extended tubular state by unrolling downwardly, and back to a rolled retracted state by rolling upwardly. An inspection camera is attached to an end of the reelable tube. Other embodiments are also disclosed.

Abstract: An object of the present invention is to provide an inspection apparatus for inspecting weld zones in a reactor pressure vessel, the inspection apparatus comprising: an ultrasonic probe 6 for emitting an ultrasonic wave; a probe holding unit 60 for holding the ultrasonic probe 6 such that a ultrasonic wave transmitting surface of the ultrasonic probe 6 is kept in direct contact with or at a constant distance from the outer surface of the reactor pressure vessel 1; a pressing unit 50 for pressing the probe holding unit 60 parallel to a central axis of a control rod drive housing 8 against the reactor pressure vessel; and a rotator 40 for rotating the probe holding unit 60 and the pressing unit 50 about the central axis of the control rod drive housing 8.

Abstract: In a clamping jig and system for inspecting spacer grids for a nuclear fuel assembly, the jig firmly and precisely clamps a variety of grids on a measurement stage moving at high speed so that, among constituent parts of the nuclear fuel assembly, the spacer grids can be inspected using a non-contact measurer. The clamping jig includes a frame having a plurality of holding recesses into which the corresponding spacer grids are inserted, supporting means mounted in each holding recess of the frame to allow each spacer grid to be adjusted from below so it can be maintained in a horizontal state, clamping means installed around each holding recess to clamp two adjacent sides of each spacer grid to a corner of the respective holding recess, and resilient means installed on the sides opposite the clamping means and resiliently supporting the other two sides of each spacer grid.

Abstract: A tool for use in servicing an LPRM assembly of a nuclear reactor vessel includes a structural member having a first bore that is structured to receive an LPRM device associated with the LPRM assembly, a headpiece provided at a first end of the structural member, and a nut engaging assembly slideably mounted on the structural member. The headpiece has a plurality of projections structured to mate with a plurality of bores provided in a seal of the LPRM assembly to enable the seal to be removed, and the nut engaging assembly has a housing that defines a second bore and that has first and second nut engaging portions. The nut engaging assembly is free to slide along the structural member and over the headpiece to a position wherein the engaging portions extend beyond the headpiece so that they may be used to remove the assembly nut.

Abstract: Method of repairing nuclear reactors that include one or more submerged lines welded to one or more support brackets may include: removing a damaged section of one of the one or more submerged lines; and replacing the damaged section of the one of the one or more submerged lines without welding. Methods of operating nuclear reactors that include one or more submerged lines welded to one or more support brackets may include: shutting down the nuclear reactor; repairing damage to at least one of the one or more submerged lines without welding; and starting up the nuclear reactor. Methods of operating nuclear reactors that include one or more submerged lines welded to one or more support brackets may include: cooling down the nuclear reactor; repairing damage to at least one of the one or more submerged lines without welding; and heating up the nuclear reactor.

Abstract: A device for monitoring a reactor during normal and off-normal operating conditions may include a case formed of a rigid material, the case including a shielding layer configured to insulate an internal portion of the device from external heat and radiation; a coupling unit configured to adhere the case to a surface location of a reactor; a sensing unit configured to generate environmental measurements by measuring environmental conditions in the vicinity of the reactor; a data processing unit configured to generate measurement data by processing the environmental measurements; a transmitter configured to transmit the measurement data externally from the device; and a power unit configured to power the device independently of an external power source.

Abstract: An apparatus and method for maintaining contact between a pod of transducers and an inner surface of a reactor pressure vessel filled with water of a nuclear power plant is described. An underwater carriage carries the pod of transducers each of which is independently movable and are constantly urged against the surface of the vessel during inspection. Each transducer is independently pivotable about two axes. Each transducer emits and receives signals to detect any flaws of potential problems in the reactor pressure vessel.

Abstract: A method and apparatus for inspecting the upper portion of a core shroud of a nuclear power plant is provided. The upper shroud scanner mounts on an arcuic section of a steam dam of the core shroud and moves back and forth there along. A vertical arm with transducers thereon extend down from a Y-car portion of the upper shroud scanner. Transducers adjacent the core shroud emit and receive an ultrasonic sound to inspect for flaws and defects in the core shroud.

Abstract: A device is provided to inspect welds in nozzles located in water within a containment vessel of a nuclear power plant. A computer connected to the device controls movement by use of thrusters located along a main rail while buoyancy packs regulate the depth. After the device is navigated to a weld needing inspection, feet extend radially outward from the main rail to secure the device in the nozzle. Then transducer clusters are moved along the main rail to be radially inside the weld to be inspected. Thereafter, the transducer clusters are extended radially outward and rotated adjacent to the weld while simultaneously emitting test signals and receiving reflected signals to indicate the condition of the weld.

Abstract: A fixture for performing visual inspections of the underside of the top guide of a boiling water reactor. The inspections are performed in the reactor vessel, under water, and includes a framed structure that rests on top of the top guide and supports a wheel track within a fuel assembly opening in the top guide, that follows the contour of the opening. A camera support, suspended from the frame, is then remotely, manually rotated to follow the contour of the wheel track as the fixture maintains the camera at a fixed angle and known constant distance from the underside of the top guide.

Abstract: Disclosed is a water jet peening method that includes the steps of: preparing a water jet peening apparatus having a supporting member, a first divider plate, a nozzle support body, and a second divider plate; inserting the water jet peening apparatus into a piping in which a structure or electronic device is mounted that is susceptible to damage by a jet of water discharged from a jet nozzle or by shock waves; disposing either the first divider plate or the second divider plate between the jet nozzle and the structure or electronic device; filling water into an internal area formed in the piping between the first divider plate and the second divider plate; and subjecting the inner surface of the piping to water jet peening by allowing the jet nozzle to discharge a jet of water into the water in the internal area.

Abstract: Vibration of a jet pump installed in a reactor pressure vessel of a boiling water reactor is monitored. Ultrasonic waves are transmitted from an ultrasonic sensor installed on an outer surface of the reactor pressure vessel toward a throat and a diffuser of the jet pump. When the ultrasonic waves reach respective outer surfaces of the throat and diffuser, reflected waves are generated at the respective outer surfaces. The ultrasonic sensor receives those reflected waves. The ultrasonic signal process section obtains a distance in the horizontal direction between the throat and the diffuser based on a time difference of the reflected waves reflected from respective reflection surfaces of the throat and diffuser and a sound speed in reactor water in the neighborhood of the throat and diffuser. A relative vibration is obtained based on the change with time of the distance.

Abstract: An inspecting device including a detachable probe has a link structure, and thus a subject having various diameters is tested. In addition, since various probes are changeably used in a scanner housing, ultrasonic wave testing and eddy current testing are simultaneously performed.

Abstract: A water-chamber working apparatus (1) that performs a predetermined work inside a water chamber (131) of a steam generator (130) including a support shaft (2) that is formed to be extendable and retractable, a rotary means (3) that is respectively provided at opposite ends of the support shaft (2) rotatably around a vertical shaft center, while coming into contact with an inner wall surface (131a) of the water chamber (131) by extension of the support shaft (2), and a movable body (4) that is provided to be movable along the support shaft (2).

Abstract: A working apparatus has: a working equipment for doing works on a structure; a folding/unfolding mechanism for conveying the working equipment to the working position in a folded state; a conveyance mechanism (such as a horizontal thruster) for conveying the working equipment and the folding/unfolding mechanism to the working position; a pressing mechanism (such as a ballast tank) for pressing the working equipment against the lower surface of the structure; and a traveling mechanism including a wheel for traveling along the lower surface of the structure and positioning the apparatus.

Abstract: An assembly adapted to access a weld extending circumferentially around a core shroud of a nuclear reactor, wherein the core shroud is contained in a pressure vessel reactor, the assembly including: a baffle plate rail having a lower surface adapted to abut a baffle plate in a gap between the core shroud and the pressure vessel reactor; a telescoping rail slidably coupled to an upper region of the baffle plate rail, and a reciprocating rail slidably coupled to an upper region of the telescoping rail, wherein the reciprocating rail includes at least one of a weld conditioning tool, a weld inspection sensor and a weld repair device.

Abstract: A plurality of signal anomalies are identified in a number of tubes in a steam generator. Since the geometry of the steam generator is known, the location of each signal anomaly along each tube is converted into a location within the interior of the steam generator. If a plurality of signal anomalies are at locations within the steam generator that are within a predetermined proximity of one another, such a spatial confluence of signal anomalies is determined to correspond with a loose part situated within the steam generator. Additional methodologies can be employed to confirm the existence of the loose part. Historic tube sheet transition signal data can be retrieved and subtracted from present signals in order to enable the system to ignore the relatively strong eddy current sensor signal of a tube sheet which would mask the relatively weak signal from a loose part at the tube sheet transition.

Abstract: An inspection robot for inspecting a nuclear reactor that includes a hull and an on-board control mechanism that controls the operation of the inspection robot. The on-board control mechanism controls one or more sensors used to inspect one or more structures in the nuclear reactor as well as the movement by the inspection robot. A gimbal mechanism rotates the inspection robot hull by shifting the center-of-mass so that gravity and buoyancy forces generate a moment to rotate the hull in a desired direction. A camera is coupled to the gimbal mechanism for providing visual display of the one or more structures in the nuclear reactor. The camera is allowed to rotate about an axis using the gimbal mechanism. The inspection robot communicates its findings with respect to the inspection tasks using the wireless communication link.

Abstract: According to an embodiment, an in-reactor operation system which is provided with a crack detection vehicle that moves in a circumferential direction along an outer surface of a shroud disposed in a reactor pressure vessel with the axis vertical, an inspection/check sensor that is mounted on the crack detection vehicle and performs an operation with respect to the shroud, a vehicle positioning mast for setting an initial position of the crack detection vehicle on the shroud, a vehicle fixation mechanism for attaching and detaching the crack detection vehicle to and from the vehicle positioning mast, and a conveyance vehicle for conveying the vehicle positioning mast on which the crack detection vehicle is mounted into the reactor pressure vessel.

Abstract: A method and an apparatus for test an annular weld at a main coolant line connected to a reactor pressure vessel in a nuclear power plant, include a self-propelled submersible vehicle which is introduced into an opened, flooded reactor pressure vessel. The submersible vehicle has at least one test device to be placed against an inner circumferential surface of the main coolant line and moved in circumferential direction of the main coolant line. The submersible vehicle is advanced into the main coolant line, which is also flooded, and is fixed in the region of the weld by radially deployable spreading or extension arms. The test device is then placed against the weld and is moved therealong in the circumferential direction.

Abstract: A construction method of a pipeline that forms a pipeline by joining tubular members to each other by butt welding, includes: a tubular member preparation step for preparing a tubular member having a smooth length of an outer surface along an axial direction from a joined end, which is set based on conditions of ultrasonic inspection of a welded portion, which are determined by usage conditions of the pipeline; a tubular member welding step for welding together prepared tubular members; and a welded portion inspection step for inspecting a welded portion by ultrasonic inspection.

Abstract: A fixture for performing visual inspections of the underside of the top guide of a boiling water reactor. The inspections are performed in the reactor vessel, under water, and includes a framed structure that rests on top of the top guide and supports a wheel track within a fuel assembly opening in the top guide, that follows the contour of the opening. A camera support, suspended from the frame, is then remotely, manually rotated to follow the contour of the wheel track as the fixture maintains the camera at a fixed angle and known constant distance from the underside of the top guide.

Abstract: An inspection system for inspecting a core shroud includes a remotely operated vehicle with a profile, scanning ability, and reliability that contribute to expanded inspection coverage and reduced inspection times.

Abstract: The present invention relates to an inspection apparatus for detecting defects in a test object in a liquid filled space. The inspection apparatus comprises an inspection body, a camera and vertical positioning equipment adapted to adjust the position of the camera in a vertical direction. The vertical positioning equipment comprises an elongated element having a vertical portion, a fastening member adapted to attach the detection device to the vertical portion, a vertical drive mechanism adapted to provide a motion of the vertical portion of the elongated element such that it moves the detection device to a desired vertical position along a vertical axis. The vertical portion of the elongated element has the property of being torsion rigid about the vertical axis.

Abstract: A welded portion inspection apparatus of a reactor pressure vessel moves on an outside surface of the reactor pressure vessel, and is provided with a scan portion having a sensor for detecting a state of the welded portion to be inspected. The apparatus has a first scan axis with a pedestal having the sensor installed for moving the sensor in a predetermined first direction to perform scanning, and a second scan axis orthogonal to the first scan axis for moving the first scan axis in a predetermined second direction. Drive portions are installed removably on both sides of the scan portion for moving the scan portion to a position of the welded portion to be inspected, and a motor is provided for driving the drive portions. The drive portions include a plurality of magnets which are endlessly formed in a line.

Abstract: A method of inspecting, performing maintenance on, or repairing a nuclear reactor may include operatively connecting a fixing device, a first track, an arm including one or more second tracks, and an effector to form an apparatus; inserting the apparatus into the reactor; fixing the apparatus within the reactor; and operating the apparatus. At least one of the one or more second tracks may include at least three track sections. The arm may have a contracted length. The arm may have an expanded length. The expanded length may be greater than two times the contracted length. The first track may include one or more motors configured to move the arm relative to the first track. A method of operating a reactor may include shutting down; inspecting, performing maintenance on, or repairing the reactor; and starting up the reactor.

Abstract: Disclosed is a nozzle stub working system for a reactor vessel that performs work inside a nozzle stub of the reactor vessel, the nozzle stub working system for the reactor vessel including: a platform unit that is provided at an upper portion inside the reactor vessel and includes a substantially cylindrical side wall portion and a bottom portion blocking the lower end of the side wall portion; an access window that is provided at the side wall portion of the platform unit to allow the inside of the platform unit to communicate with the nozzle stub; an access window moving device that opens and closes the access window; a working device that advances from the inside of the platform unit to the inside of the nozzle stub to perform work inside the nozzle stub; and a control device that is provided at the outside of the reactor vessel and controls the access window moving device and the working device, wherein the control device drives the access window moving device to open the access window, drives the workin

Abstract: An assembly for detecting and measuring the fouling rate by deposits containing at least one ferromagnetic material, including a probe which can be continuously moved inside a tube and which has a body carrying on its outer surface at least one magnetized source for self-orientation of the body of the, at least three magnetic field emitters and at least three magnetic field detectors each positioned between two contiguous emitters.

Abstract: A vibration measuring apparatus for nuclear reactor internal structure includes a holder which has an opening contact on a surface of a pressure vessel of a nuclear reactor; a vibrator accommodated in the holder so as to transmit or receive an ultrasonic wave; a couplant with which the holder is filled up; and, a bias component applies a biasing force to the vibrator in the direction of the opening; The couplant is a solid state of metal material at normal temperature and change to liquid stage by heat transfer from the pressure vessel.

Abstract: A remote, precise gap-measuring apparatus for automatically measuring the gap between reactor internals, including a nuclear reactor vessel, a core support barrel, a core shroud, and a lower support structure. The remote, precise gap-measuring apparatus includes digital probes measuring a gap between a nuclear reactor vessel protrusion and a core support barrel protrusion. The nuclear reactor vessel protrusions are disposed on an inner surface of the nuclear reactor vessel, and the core support barrel protrusions are disposed on an outer surface of the core support barrel, engaged with the nuclear reactor vessel protrusions. The apparatus includes a computer coupled to the digital probes to display and store measured values of the gap. A solenoid valve, controlled by the computer, controls compressed air supplied through an air hose to operate the digital probe.

Abstract: A tool for inspecting a cell formed by grid beams of a top guide structure in a nuclear reactor is provided. The tool includes a camera; a support structure coupled to the camera for contacting at least one of the grid beams to support the camera within the cell; and at least one actuator moving the camera with respect to the support structure and along one of the grid beams, the at least one actuator coupling the camera to the support structure. A method for inspecting a cell formed by grid beams of a top guide structure in a nuclear reactor is also provided.

Abstract: According to an embodiment, a pressurized water reactor plant has a primary system which includes: a reactor vessel for housing a reactor core which is cooled by a primary coolant, a single steam generator, a hot leg pipe for connecting the reactor vessel and the steam generator, cold leg pipes, at least two primary coolant pumps, and a pressurizer for pressurizing the primary coolant pressure boundary in which the primary coolant flows. The plant also has: a passive cooling and depressurization system which is a primary depressurization means for equalizing the primary system pressure to the secondary system pressure at the time of a tube rupture accident of the steam generator, and a reactor containment vessel containing the primary system and cooling the primary system by air cooling. Thus, a compact pressurized water rector with high economic efficiency, safety, and reliability can be provided.

Abstract: The present invention relates to a method of detecting deposits comprising at least one ferromagnetic material, such as nickel, magnetite or the like, on or near the external wall of a tube, notable in that it comprises at least the following steps of: moving a magnetized source inside the tube in the lengthwise direction using an electric motor, measuring the strength of the current in the electric motor, and determining the position and/or the thickness and/or the volume of the said deposit as a function of the variations in the strength of the current measured in the electric motor. Another subject of the invention is a device implementing the said method.

Abstract: An object of the present invention is to provide an inspection apparatus for inspecting weld zones in a reactor pressure vessel, the inspection apparatus comprising: an ultrasonic probe 6 for emitting an ultrasonic wave; a probe holding unit 60 for holding the ultrasonic probe 6 such that a ultrasonic wave transmitting surface of the ultrasonic probe 6 is kept in direct contact with or at a constant distance from the outer surface of the reactor pressure vessel 1; a pressing unit 50 for pressing the probe holding unit 60 parallel to a central axis of a control rod drive housing 8 against the reactor pressure vessel; and a rotator 40 for rotating the probe holding unit 60 and the pressing unit 50 about the central axis of the control rod drive housing 8.

Abstract: An object of the present invention is to provide an inspection apparatus for inspecting weld zones in a reactor pressure vessel, the inspection apparatus comprising: an ultrasonic probe 6 for emitting an ultrasonic wave; a probe holding unit 60 for holding the ultrasonic probe 6 such that a ultrasonic wave transmitting surface of the ultrasonic probe 6 is kept in direct contact with or at a constant distance from the outer surface of the reactor pressure vessel 1; a pressing unit 50 for pressing the probe holding unit 60 parallel to a central axis of a control rod drive housing 8 against the reactor pressure vessel; and a rotator 40 for rotating the probe holding unit 60 and the pressing unit 50 about the central axis of the control rod drive housing 8.

Abstract: An underwater remote inspection device is provided with an etching device and a magnifying observation device mounted to a supporting member. A chamber of the etching device is provided with a negative electrode, a positive electrode and a sealing device, and is connected to an etchant supply pipe and an etchant exhaust pipe. A single pair of annular sealing members of the sealing device is provided to a distal end portion of the chamber. A suction passage formed in the side wall of the chamber communicates to a sealing region formed between the sealing members. The magnifying observation device is provided with a magnifying camera in a waterproof container and a plurality of LED lights are installed to the waterproof container. The underwater remote inspection apparatus can prevent leakage of an etchant and reduce execution time of etching.

Abstract: An object of the present invention is to provide an inspection apparatus for inspecting weld zones in a reactor pressure vessel, the inspection apparatus comprising: an ultrasonic probe 6 for emitting an ultrasonic wave; a probe holding unit 60 for holding the ultrasonic probe 6 such that a ultrasonic wave transmitting surface of the ultrasonic probe 6 is kept in direct contact with or at a constant distance from the outer surface of the reactor pressure vessel 1; a pressing unit 50 for pressing the probe holding unit 60 parallel to a central axis of a control rod drive housing 8 against the reactor pressure vessel; and a rotator 40 for rotating the probe holding unit 60 and the pressing unit 50 about the central axis of the control rod drive housing 8.

Abstract: A device and method for measuring the back pressure in chemical reactor tubes includes many automated features. Inflatable tube seals may be automatically inflated. The device may measure several tubes at once. It may transmit data electronically to a remote computer for analysis and graphic display.

Abstract: An apparatus and method for remote frequency-based inspection of a valve seat includes inserting a frequency-based inspection tool into an inspection position over the valve seat and contacting the one or more supports to the inner surface of the valve seat. An input signal is transmitted at a desired frequency through the valve seat to a joint between the valve seat and a valve shaft via the one or more transducers. The shaft is rotated to remotely rotate the fixture, thereby allowing an inspection of an entire perimeter of the joint. An output signal is received and is evaluated to determine if an anomaly is present in the joint.

Abstract: A working apparatus has: a working equipment for doing works on a structure; a folding/unfolding mechanism for conveying the working equipment to the working position in a folded state; a conveyance mechanism (such as a horizontal thruster) for conveying the working equipment and the folding/unfolding mechanism to the working position; a pressing mechanism (such as a ballast tank) for pressing the working equipment against the lower surface of the structure; and a traveling mechanism including a wheel for traveling along the lower surface of the structure and positioning the apparatus.

Abstract: A tool assembly provides for brushing circumferential welds in a restrictive access area between a cylindrical inner member and a cylindrical outer member such as the shroud and vessel in a nuclear reactor. The tool assembly includes a circumferential plate sized larger than an outside diameter of the inner member and smaller than an inside diameter of the outer member. At least one renew brush is coupled with the circumferential plate, and a motor is coupled with the renew brush that rotates the renew brush. A driving assembly mounted between the inner member and the outer member engages the circumferential plate and circumferentially drives the circumferential plate in the restrictive access area.

Abstract: A handling method for a natural circulation boiling water reactor having a chimney having cylindrical chimney shell disposed above a core in a reactor pressure vessel, a plurality of square tubes disposed in the chimney shell, and a grid support plate with grid holes supporting and in communication with a lower end portion of the square tubes so that adjacent square tubes are disposed at an interval which exceeds the width of one square tube between them. The method includes steps shifting predetermined ones of the square tubes to the interval between the square tubes, and performing maintenance and inspection of members around a core via the grid holes which appear at positions from which the predetermined square tubes are taken out due to the shift of the predetermined square tubes.

Abstract: An apparatus for inspecting a nuclear reactor may include a track, arm, fixing device, and effector. The arm may be operatively connected to the track, the fixing device may be operatively connected to the track, and the effector may be operatively connected to the arm. The arm may have contracted and expanded lengths. The expanded length may be greater than two times the contracted length. The track may include one or more motors adapted to move the arm relative to the track. A method of inspecting, performing maintenance on, or repairing a reactor may include: operatively connecting a fixing device, track, arm, and effector to form an apparatus; inserting the apparatus into the reactor; fixing the apparatus within the reactor; and operating the apparatus. A method of operating a reactor may include shutting down; inspecting, performing maintenance on, or repairing the reactor; and starting up the reactor.

Abstract: An operation method and apparatus in a pressure vessel of a nuclear reactor is provided. The operation apparatus including a body and a guide inserted from the upper side of the nuclear reactor to an interior of the jet pump. The operation apparatus circulate water inside the pressure vessel. The guide is positioned at the end of a body of the operation apparatus, and is inclined with respect to the center axis of the body so as to be inserted into a side opening of the jet pump.

Abstract: A device and method for measuring the back pressure in chemical reactor tubes includes many automated features. Inflatable tube seals may be automatically inflated. The device may measure several tubes at once. It may transmit data electronically to a remote computer for analysis and graphic display.

Abstract: A working apparatus has: a working equipment for doing works on a structure; a folding/unfolding mechanism for conveying the working equipment to the working position in a folded state; a conveyance mechanism (such as a horizontal thruster) for conveying the working equipment and the folding/unfolding mechanism to the working position; a pressing mechanism (such as a ballast tank) for pressing the working equipment against the lower surface of the structure; and a traveling mechanism including a wheel for traveling along the lower surface of the structure and positioning the apparatus.

Abstract: A method for executing water jet peening for giving an impact force to a surface of a structure member by a crushing pressure of a water jet and cavitation and improving residual stress, or washing, or reforming said surface, wherein said water jet peening is executed so as to make a natural frequency of oscillation of said structure member and a excitation frequency of oscillation of water jet peening different from each other.

Abstract: A BWR steam dryer remote visual inspection system including a support moveable along a first axis over the steam dryer, the support having a longitudinal direction; a trolley movable along the support in the longitudinal direction; a mast fixed to the trolley and moveable at a predetermined angle with respect to a plane defined by the first axis and longitudinal direction; and a camera coupled to an end of the mast.

Abstract: In a method and a device for testing a weld seam (8), located on the inner surface of a reactor pressure vessel (2), by which the outer circumference of an instrumentation nozzle (4) leading into the interior of this reactor pressure vessel (2) is welded onto the reactor pressure vessel (2), an ultrasound test probe (20) with a linear ultrasound transducer array (30) is inserted into the instrumentation nozzle (4), which ultrasound transducer array (30) is parallel to the central axis (12) of the instrumentation nozzle (4) in terms of its longitudinal direction, and is used to couple a transmitted ultrasound signal (S) into the instrumentation nozzle (4) in the region of the weld seam (8) and to receive a reflected ultrasound signal (R).

Abstract: Two transducers to be rotated around a circumferential location on a cylindrical body for structural testing of the body are carried on a mounting and drive apparatus including a magnetic attachment which can be manually brought up to a pipe from one side only for fixed connection to the pipe on that side at a position axially spaced from a weld. A collar shaped support for the pair of transducers is formed of a row of separate segments which wrap around the pipe from the one side and is rotated around the axis of the pipe to carry the transducer around the circumferential weld. The segments carry rollers to roll on the surface and are held against the pipe by magnets. The transducers are carried on the support in fixed angular position to track their position but in a manner which allows slight axial or radial movement relative to the pipe.