Abstract: An external focused ultrasonic beam, non-destructive, open-air, inspection method of sheet metal spot and seam weldments using a probe in combination with motion measurement of the probe over the weldments during inspection without immersion of the material. Reflected ultrasonic waves are received and signals produced and processed or displayed as A-scan, B-scan and C-scan images that are easily recognized. An A-Scan is based on the time-of-flight difference between the outer surface, the weldment and inner and opposite surfaces of the component. B-scan and C-scan indicate the degree of weld fusion and provide data relative to fused thickness and defects sheet metal or welds. A special purpose scanner that enables ultrasonic examination welds. Scanner is pencil like ultrasonic probe with bearing face and position sensing device disposed adjacent a weld position. Scanner collects data for method to determine various characteristics of welded items.

Abstract: Spot and seam weldments in sheet metal components are inspected by a method in which a focused ultrasonic beam is directed into the weldment from the outside surface together with measuring the motion of the ultrasonic beam over the weldment. Reflected ultrasonic waves are received and signals indicative thereof are produced and processed or displayed as image forms that are easily recognized by an operator. This data is displayed as an A-Scan where a predetermined time window is established on the display, based on the time-of-flight difference between the outer surface, the weld interface or interfaces and the inner or opposite surface of the component. Certain ultrasonic signals are indicative of the degree of complete fusion in the weld zone and provide data relative to the total fused thickness and to defects either in the sheet metal or in the weld.

Abstract: An ultrasonic image process and system for accurately evaluating the quality of a weld using ultrasonic responses and operator entered data to enhance the quality of weld inspection. Ultrasonic responses useful in accurately indicating the actual location of the weldment, detecting the actual component thickness and the location and characteristic of any other relevant ultrasonic reflectors located in or near the weld heat effected zone are input to a composite image of a weldment for the purpose of enhancing the quality and the ease of detecting, evaluating and sizing of weld defects. Through the superposition of ultrasonic image data from additional complimentary sensors and operator inputs based on prior known data, useful images can be formed to improve the decision making in weldment inspection and evaluation.

Abstract: An improved method for repair of incore-instrumentation-housing and related defects in a nuclear reactor system involves three stages, each with ultrasonically assisted inspections. In the first stage, a defective incore housing is removed and the exposed area and aperture at the former location of the incore housing is ultrasonically inspected using an ultrasonic probe with a tiltable disk-shaped head that self-conforms to the local contour of the reactor vessel bottom. In the second stage, a weld buildup is formed. The reactor is then sealed and the weld buildup is machined to define an aperture therethrough. The weld buildup is then ultrasonically inspected with a second probe with a centering member that is stationary as the probe body is moved vertically relative to it. In the third stage, a J-prep is formed. A new incore housing is inserted through the weld buildup aperture. The new incore housing is welded at the J-prep. The J-weld is ultrasonically inspected using a third ultrasonic probe.

Abstract: An improved method for repair of incore-instrumentation-housing and related defects in a nuclear reactor system involves three stages, each with ultrasonically assisted inspections. In the first stage, a defective incore housing is removed and the exposed area and aperture at the former location of the incore housing is ultrasonically inspected using an ultrasonic probe with a tiltable disk-shaped head that self-conforms to the local contour of the reactor vessel bottom. In the second stage, a weld buildup is formed. The reactor is then sealed and the weld buildup is machined to define an aperture therethrough. The weld buildup is then ultrasonically inspected with a second probe with a centering member that is stationary as the probe body is moved vertically relative to it. In the third stage, a J-prep is formed. A new incore housing is inserted through the weld buildup aperture. The new incore housing is welded at the J-prep. The J-weld is ultrasonically inspected using a third ultrasonic probe.

Abstract: An automated system for examining incore housing welds in a nuclear reactor from above is disclosed. The probe uses both ultrasonic and eddy current non-destructive inspection coils to examine the weld for indications, or flaws. It is inserted into the incore housing tube from above because of the high radiation exposure workers experienced using the prior method of inserting a probe into the incore housing from below. This is conveniently done when the incore flux monitors are removed during standard maintenance, and is performed from the refueling bridge.

Abstract: An apparatus and process for the remote inspection for stress corrosion cracking of welded shut boiling water reactor shroud access cover plates is disclosed. The apparatus consists of a streamline housing having a top side with lugs for the attachment of lowering lines on either end of the housing. Medially of the streamline housing and projecting downwardly from the bottom of the streamline housing, there is provided a central rotating pedestal with a rubber base. The rotating pedestal and rubber base enable the entire housing to rest on and rotate relative to the pedestal and rubber base. A first motor interior of the housing rotates the housing at a bevel gear rigidly mounted to the central pedestal. A second motor rotates a threaded shaft driving a ball screw with an attached mount for an ultrasound transducer. The mount and transducer responsive to rotation of the ball screw traverse along the elongate dimension of the housing over an opening through the bottom of the housing.

Abstract: In operation, the device is lowered with paired lines attached to both housing lugs but suspended under tension only from one line to one lug so that the streamline housing is vertically disposed. With the housing vertically disposed during lowering, obstacles can be avoided such as the guide rod for the steam separator and dryer as well as the feedwater and core spray spargers. When lowered to the vicinity of the ledge and cover plate to be inspected, the slack line is fished around any obstacle and thereafter placed under tension. The streamline housing is then lowered using both lines in a horizontal position so as to expose downwardly the pedestal and rubber foot. Lowering is completed with remote camera assistance. Sample sweeps with the ultrasound transducer of spaced apart sections of the cover plate weld are used for precise centering of the pedestal and rubber base with respect to the center of the cover plate.

Abstract: In a boiling water reactor, an apparatus and process for ultrasound inspection of the top guide is disclosed. The top guide constitutes a lattice of stainless steel bars overlying the core plate and being assembled at confronting grooves with the lattice mounted at the side edges to the reactor pressure vessel. This lattice braces the upper ends of the vertically supported fuel assemblies in their requisite orientation and spaced apart relation to enable among other things the required spatial interval to be maintained for control rod moderation of the reaction. Because of the proximity of the top guide to the fuel assemblies, the individual bars making up the lattice need to be checked for cracking, especially that cracking produced by irradiation assisted stress crack corrosion. With a defined cell in the lattice emptied of its contained and adjoining fuel assemblies, there is disclosed an ultrasound test for cracking.

Abstract: An apparatus for the remote examination of peripheral shroud hold down bolts on steam separators used in boiling water reactors is disclosed. The testing apparatus is used while the steam separator is in a holding pool. The testing apparatus includes a depending pole having attached at the bottom thereof an aluminum shoe. The shoe has a flat, upwardly exposed bottom and opens to one side at gathering surfaces to receive the lower ends of the shroud bolts. The upwardly exposed bottom of the shoe defines an aperture through which an upwardly exposed piezoelectric device is exposed for direct contact with the bottom of the bolt. An overlying clamp member is provided to clamp the lug onto the bottom of the shoe for testing. The clamp member defines a receiving slot to receive the shaft of the bolt immediately overlying the rectangular lug. The clamp member slides over the shaft at the slot into contact with the top of the lug.

Abstract: Apparatus for remotely controlled examination of the control rod drive penetration stub tubes in the wall of a nuclear reactor pressure vessel including a rotatable carriage on which is mounted a reciprocable shaft to which is attached an inspection instrument for scanning the stub tubes.