Abstract: A system and method for inspecting a spot weld on a workpiece. The system may include an actuator, an inspection assembly coupled to the actuator, and a controller electronically coupled to the inspection assembly. The inspection assembly may include an ultrasound device and one or more adjustment motors coupled to the ultrasound device.

Abstract: A method of inspecting a part in immersion using a focused beam of ultrasound waves oriented perpendicularly to the surface of the part, the method including, when the axis of the focused beam is close to an edge of the part, tilting the axis towards the edge relative to the normal to the surface of the part in order to eliminate the lateral shadow zone over all or substantially all of the depth of the part.

Abstract: An apparatus for the ultrasonic testing of internal areas of prefabricated composite assemblies as described. The composite assemblies have one or more internal areas formed therein. The apparatus includes at least one receive transducer, at least one transmit transducer, a vertical member, a support member slidably attached to the vertical member, a pair of substantially parallel hollow rods, and an ultrasonic testing system. Each rod comprises a transducer attachment end with receive transducers attached to the transducer attachment end of a first rod, and transmit transducers attached to the transducer attachment end of a second rod. The rods are slidably attached to the support member and manually movable with respect to a composite assembly to be tested. The ultrasonic testing system is coupled to the receive transducers through the first rod, and coupled to the transmit transducers through the second rod.

Abstract: An apparatus and method for inspecting a structure are provided which include probes with sensing elements and are disposed proximate the opposite surfaces of a structure, where only one of the probes need be driven. A tracking probe may be magnetically coupled to a driven probe and move in coordination therewith. Ring magnets may be used in the driven and tracking probes to provide the magnetic coupling and align sensing elements disposed in the centers of the ring magnets. The probes include ball bearings such as ball and socket bearings for supporting the structure and maintaining the desired orientation and spacing of the probes relative to the structure. A fluid, such as water or pressurized air, may be used as a couplant between an ultrasonic transducer and the structure. A water column skirt may be used to with a probe employing ball bearings for support.

Abstract: An apparatus and method for inspecting a structure are provided which include probes with sensing elements and are disposed proximate opposite surfaces of a structure, where only one of the probes need be driven. A tracking probe may be magnetically coupled to a driven probe and move in coordination therewith. Ring magnets may be used in the driven and tracking probes to provide the magnetic coupling and align sensing elements disposed in the centers of the ring magnets. The probes may include a fluid bearing, such as a water bearing or an air bearing, for supporting the structure and maintaining the desired orientation and spacing of the probes relative to the structure. The fluid of a fluid bearing may be used as a couplant between an ultrasonic transducer and a structure. A flow moderating skirt may be used to with a probe employing a fluid bearing for support.

Abstract: A method for inspecting a gas turbine engine component includes positioning an ultrasonic probe assembly proximate to a surface of the component, wherein the ultrasonic probe assembly includes a body portion and an inspection bar, coupling the inspection bar to the body portion such that the inspection bar is substantially vertical with respect to the body portion, moving the ultrasonic probe assembly along a substantially horizontal axis while generating ultrasonic data of the component, coupling the inspection bar to the body portion such that the inspection bar is substantially horizontal with respect to the body portion, moving the ultrasonic probe assembly along a substantially vertical axis while generating ultrasonic data of the component, and utilizing the generated data to reconstruct an image of the component.

Abstract: Improved methods, systems, and apparatus for inspecting a structure using angle beam shear wave through-transmission ultrasonic signals involves positioning transducers at offset positions on opposing sides of the structure and permits inspection of the inside of the structure beneath surface defects and features. Magnetic coupling can be used for supporting a pair of leader-follower probes and defining offset positions between angle beam shear wave transducers carried by the probes. Inspection data can be collected for supporting real-time generation of three-dimensional image representations of the structure and of internal defects and features of the structure. Image generation and resolution using inspection data from angle beam shear wave ultrasonic signals can be supplemented using pulse-echo ultrasonic inspection data.

Abstract: An apparatus and method aligning magnetically coupled inspection probes are provided. In this regard, a tracking probe may be magnetically coupled to a driven probe and move in coordination therewith. An alignment compensator for magnetically coupled inspection probes offsets misalignments between a driven probe and a tracking probe. Misalignments between magnetically coupled probes may be caused by gravity, friction, and movement of the probes. An alignment compensator may use one or more magnets, or electromagnets, to improve the alignment of the probes. An alignment compensator may include a control system for adjusting the power to an electromagnet or repositioning a magnet to offset misalignment of probes.

Abstract: A miniature air gap inspection crawler. The miniature air gap inspection crawler may include a base, a linear drive mechanism and a circumferential drive mechanism such that either the linear drive mechanism or the circumferential drive mechanism may be employed, and an inspection module connected to the base.

Abstract: A method and apparatus is provided for inspecting material arranged within an annular recess such as weld beads, particularly weld beads between the shroud, core plate and support structures within a boiling water nuclear reactor (BWR). The apparatus comprises a track support, a generally arcuate track, a carriage, a sensor support and a sensor. The track is configured to correspond and align generally with an inner surface of a shroud or other encompassing structure with the sensor support and sensor configured to be extended into and then moved horizontally along the annular recess. The sensor may be configured with a plurality of sensor elements, such as ultrasonic transducers or eddy current sensors that may be configured to analyze different properties or different regions relative to the sensor location.

Abstract: Method and implementing apparatus useful in acquiring data on acoustic features within a sample provides a pulsed acoustic probe and a stage system for effecting relative movement between the sample and the probe. The stage system is commanded such that the probe interrogates a non-rectangularly bounded space on the sample surface or within the volume of the sample. Acoustic energy reflected from or transmitted through the sample is sensed. Amplitude signals are developed from the sensed acoustic energy. Data characterizing the developed amplitude signals are stored for subsequent processing.

Abstract: In a method and a device for the ultrasonic monitoring of overlapping welded joints between a first sheet and a second sheet pulses are irradiated at an angle of between 15 and 80° into the first sheet by a first rotating probe head. The rotating probe head is arranged on a mount and has a tire rotating about the axle, coupled to the ultrasound transmitter and rolling along the first sheet, parallel to the overlapping welded joint. On ultrasound investigation of the overlapping welded joint the impulses transmitted to the second sheet are received by a second receiving rotating probe head, of similar construction to the first rotating probe head.

Abstract: A dynamically configurable ultrasound transducer element and related circuits and methods. The transducer may comprise an array of capacitive transducer elements, a row decoder coupled to said array of capacitive transducer elements, a column decoder coupled to said array of capacitive transducer elements, a bias voltage source coupled to said row decoder, and a driving signal source coupled to said column decoder. Preferably, a master clock also is provided to allow for a synchronization of signals between the row decoder and column decoder.

Abstract: A method and apparatus for temperature-controlled ultrasonic inspection of an object. The temperature of a coupling medium between an ultrasonic transducer and an object under inspection is controlled to be at a predetermined temperature for which the attenuation of the ultrasonic energy in the coupling medium is reduced compared to the attenuation at an ambient temperature. This improves the efficiency of ultrasonic energy transport between the ultrasonic transducer and the object. The temperature of the object is controlled to simulate operating conditions more closely. An ultrasonic inspection system includes a temperature controller operable to maintain the temperature of the coupling medium and/or an object under inspection at a set temperature.

Abstract: Averaged guided wave inspection method for a throttle cable is disclosed. Access to the engine end of the throttle cable is obtained and a transducer is applied to an end of the ribbon cable. The transducer generates an ultrasonic guided wave in the cable. The ultrasonic guided wave propagates down the entire length of the cable and reflects back from any discontinuity in the cross section of the ribbon cable. By determining the time needed for the reflected wave to travel back to the receiver, the location of any defect along the length of the cable can be determined. By moving the ribbon cable and transducer to different positions with respect to the sheath of the throttle cable, repeating the prior steps and averaging, unwanted noise caused by external influences is eliminated.

Abstract: An apparatus and method for inspecting a structure are provided in which probes including respective sensing elements, such as ultrasonic transducers, are disposed proximate the opposed surfaces of a structure, but only one of the probes need be driven. In this regard, a tracking probe may be magnetically coupled to a driven probe and move in coordination therewith. The apparatus and method can therefore inspect structures in which one surface is inaccessible. The probes may permit liquid to be bubbled between the ultrasonic transducer and the structure in order to couple the ultrasonic signals. By utilizing a bubbled liquid as a couplant, the apparatus and method may operate in an ultrasonic array mode. Additionally, the probes may include at least one contact member, such as a plurality of wheels, for contacting the structure in order to maintain the desired orientation and spacing of the probes relative to the structure.

Abstract: Methods and apparatus for ultrasonically scanning cylinders are provided. The methods and apparatus employ as few as one ultrasonic sensor for full immersion scanning and defect detection. Self-centering fixturing spins the cylinder, reducing vibration, allowing for fast ultrasonic scans. To create the 45 degree angle beam shear waves for the circumferential scans, the ultrasonic sensor is offset from the centerline of the cylinder, creating the correct angle for excitation of the shear wave.

Abstract: The present technique provides a system and method for ultrasonically testing a tubular good along the entire axial length of the material using a single ultrasonic test assembly. The ultrasonic test assembly has an ultrasonic tubular inspection unit movable lengthwise along a tubular and an end-crossing extension mechanism adapted to facilitate end inspection of the tubular.

Abstract: A system and method for delivering a laser beam from a remote laser source through a gantry positioning system for performing ultrasonic testing on a test object. The invention provides for closed-loop error correction of a laser beam delivered through the gantry members of a gantry positioning system (GPS) to ensure unobstructed transmission of the laser beam as the GPS changes operates and changes shape. The invention provides for ultrasonic testing of a test object for identifying material defects by moving the end gantry member of the GPS thereby permitting data acquisition of the test object from various fields of view. The invention also provides for controlling the divergence of the laser beam used for ultrasonic testing.

Abstract: The invention is directed to an apparatus and method for inspecting spring hold down bolts of an upper tie plate of a fuel rod assembly in a nuclear reactor and includes an inspection fixture adapted to be aligned with the upper tie plate of the nuclear reactor fuel rod assembly for placement into a position for rapid and easy insitu inspection of the hold down bolts of the upper tie plate. The fixture is provided with a plurality of ultrasonic transducers which are positioned on the fixture so that when the fixture is placed into the inspection position each transducer will be located proximate to one of the hold down bolts for conducting effective ultrasonic scanning of the bolt while the bolt is in place. A multi-channel ultrasonic flaw detector is connected to each of the transducers for indicating whether there are any flaws in each of the hold down bolts when the fixture is placed into the inspection position and the ultrasonic transducers are activated.

Abstract: An ultrasonic aligning device for laterally aligning a rail testing device with respect to a rail has an ultrasonic transducer formed of an array of closely spaced ultrasonic elements, with center to center distances between elements being selected to determine incremental lateral positions of the array relative to the rail. The ultrasonic elements are selectively actuated to cause the generation of ultrasonic beams towards the base portion of the rail. Reflections from the base portion are detected to produce reflection signals representative of the incidence of the ultrasonic beam onto said base portion. The reflection signals are processed by a reflection analyzer for a determination of the lateral offset of the ultrasonic array relative to the rail. A position signal indicative thereof is produced and used to laterally displace the array to achieve a desired lateral alignment of the rail testing device with the rail.

Abstract: A dynamically configurable ultrasound transducer element and related circuits and methods. The transducer may comprise an array of capacitive transducer elements, a row decoder coupled to said array of capacitive transducer elements, a column decoder coupled to said array of capacitive transducer elements, a bias voltage source coupled to said row decoder, and a driving signal source coupled to said column decoder. Preferably, a master clock also is provided to allow for a synchronization of signals between the row decoder and column decoder.

Abstract: An end effector for supporting an ultrasonic testing probe on a robot arm having a robot mounting bracket for use in a nuclear reactor pressure vessel. The end effector has a wrist assembly with a rotatable wrist axle. The wrist assembly is coupled to the robot mounting bracket and a probe assembly is coupled to the wrist shaft. The ultrasonic testing probe is floatably disposed within the probe assembly.

Abstract: A movement control mechanism of contact-type vibrating probe is provided, where the contact-type vibrating probe can be used as a probe for profiling measurement and continuous measurement and configuration of a workpiece can be measured with high accuracy. The movement control mechanism for controlling movement of a support body (23) which moves a contact-type vibrating probe (100) having high detection accuracy includes a vibrator for vibrating the stylus in an axial direction, a detector (5) for detecting a vibration of the stylus by the vibrator, second vibrator for vibrating the stylus in a direction approximately parallel to an end surface of the workpiece, and a controller (31) for controlling movement of the support body (23) so that change in state quantity of a detection signal detected by the detector is constant.

Abstract: An apparatus for ultrasonically examining a weld in a nuclear steam supply system includes an elongated guide rod for positioning within a pipe of the nuclear steam supply system. An ultrasonic transducer is positioned at an end of the elongated guide rod. A collapsible shoe encloses the ultrasonic transducer. The collapsible shoe includes a biasing mechanism to allow the collapsible shoe to pass through the pipe while the pipe is at a first circumference and while the pipe is at a second circumference. The collapsible shoe continuously contacts the pipe to establish ultrasonic coupling for the ultrasonic transducer.

Abstract: Detecting a defect in the sample is accomplished by photoacousticly exciting acoustic longitudinal, surface Rayleigh, and shear waves at a first point on a near surface of a sample; photoacoustically detecting acoustic waves at a second point spaced from the excitation first point for intercepting shear waves reflected from the far surface of the sample at approximately the angle of maximum shear wave propagation; and detecting the energy level of the intercepted reflected shear waves representative of the flaw in the sample.

Abstract: The present invention provides a mounting assembly, for use with an ultrasound transducer attached to an ultrasound machine, for determining the spacial relationship between a succession of 2D image slices of a target of a subject, generated by the ultrasound machine. The mounting assembly comprises: (i) means to mount an ultrasound transducer; (ii) means to engage a surface of the subject in the proximity of the target, the means to engage a surface being moveably attached to the means to mount an ultrasound transducer; and (iii) sensing means, in communication with the means to engage a surface, to measure the movement of the means to engage a surface during acquisition of the succession of 2D image slices. Preferably, the sensing means comprises a tilt sensor and a displacement sensor.

Abstract: A method and a device for switching between different types of output signals, wherein it is possible to generate at least two different types of output signals by the position measuring system which are transmitted to an evaluating unit. Switching between the different types of output signals takes place by one or several switching signals transmitted by the evaluating unit, which are transmitted over a supply line of the position measuring system.

Abstract: An ultrasonic aligning device for laterally aligning a rail testing device with respect to a rail has an ultrasonic transducer formed of an array of closely spaced ultrasonic elements, with center to center distances between elements being selected to determine incremental lateral positions of the array relative to the rail. The ultrasonic elements are selectively actuated to cause the generation of ultrasonic beams towards the base portion of the rail. Reflections from the base portion are detected to produce reflection signals representative of the incidence of the ultrasonic beam onto said base portion. The reflection signals are processed by a reflection analyzer for a determination of the lateral offset of the ultrasonic array relative to the rail. A position signal indicative thereof is produced and used to laterally displace the array to achieve a desired lateral alignment of the rail testing device with the rail.

Abstract: An ultrasonic one pass inspection system for determining the presence, location, and size of flaws in laminated structure such as an “I” stiffener in a single inspection cycle. The exemplary system includes an immersion tank, six (6) single probes, 184 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stiffener. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stiffener with respect to the position of the transducer. The position encoder is spring-loaded against the stiffener.

Abstract: An ultrasonic one pass inspection system for determining the presence, location, and size of flaws in laminated structure such as an “I” stiffener in a single inspection cycle. The exemplary system includes an immersion tank, six (6) single probes, 184 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stiffener. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stiffener with respect to the position of the transducer. The position encoder is spring-loaded against the stiffener.

Abstract: An ultrasonic one pass inspection system for determining the presence, location, and size of flaws in laminated structure such as an "I" stiffener in a single inspection cycle. The exemplary system includes an immersion tank, six (6) single probes, 184 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stiffener. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stiffener with respect to the position of the transducer. The position encoder is spring-loaded against the stiffener.

Abstract: A device and method for data transmission between a transducer and a processing unit which are coupled by one or several signal transmission lines, to selectively activate at least two different modes of operation of the transducer. The device includes a comparator unit which identifies the respectively activated mode of operation by comparing signals present on at least one signal transmission line with predetermined reference signals.

Abstract: Radially spaced calibration holes are drilled parallel to the exterior surface of a cylindrical shell for a dryer roll. An ultrasonic transducer is mounted in a fixture filled with a coupling medium which allows for adjustment of the spacing and angle of the transducer which traverses the shell as it is rotated. The transducer produces a signal directed to the shell. A computer calculates the time the signal takes to travel from and return to the transducer and the depth of the shell from which the signal returns. A clear signal corresponding to holes up to one inch from the surface are found by adjusting the ultrasonic transmission angle. This angle is approximately 23 degrees from a normal to the casting surface. The calibrated transducer traverses the surface of the shell. The signals are gathered and stored to create data which may be used in maintaining the shell for the dryer roll.

Abstract: A method of non-destructively evaluating or validating a processed area of an object such as a metallic laser shock peened surface by determining Rayleigh wave angles at various positions on the surface.

Abstract: The present invention relates to ultrasonic resonators comprising a resonator chamber body (11) and one or more electroacoustic transducers (13, 14). The resonator body consists of a non-piezoelectric material; it forming a resonant cavity for accommodating a specimen. This resonant cavity is configured so that between the acoustically excitated internal walls a resonant wave field of standing linear acoustic waves is formed. The electroacoustic transducer(s) is(are) acoustically coupled externally to said resonator chamber body (FIG. 2) fixedly or removably or movably.

Abstract: Typically, paint film thickness is measured at a plurality of locations on a vehicle body by a hand-held sensor which is positioned by an operator at a position normal to the respective locations being sensed. This operation may be inaccurate and time-consuming because substantial reliance is placed upon the operator. The invention provides an apparatus for positioning a plurality of sensors in contact with a plurality of locations, respectively, on a non-planar surface such that each sensor is positioned normal to the non-planar surface at the respective location on the surface. The apparatus includes a movable fixture and a plurality of pistons carried by the movable fixture. Each of the pistons is movable independently with respect to the fixture. Each piston includes a distal end, and a sensor is pivotally mounted to each distal end.

Abstract: When an ultrasonic transducer for detecting discontinuities and/or delaminations in a thin layer of coated material applied to a metal plate or the outside wall or surface of a cast iron dryer cylinder is directed at the coated surface to be inspected at a particular angle, about 10 percent of the single will appear as Harris waves which propagate into the coated test plate at 90 degrees to the surface. This signal which propagates vertically is polarized, with the result that the signal has a greatly improved signal-to-noise ratio. For incident medium of Lucite and employing shear wave refracting in the medium of Lucite, the specific angle is approximately 66 degrees from the vertical for best signal-to-noise ratio. Shear or longitudinal waves can be employed to affect the detection of subsurface defects with the particular angle changing depending on the relation of the velocity of the sound waves in the refracting medium to the velocity of sound waves in the incident medium.

Abstract: An ultrasonic inspection apparatus and method tests elongated, cylindrical aluminum billets. The apparatus includes a frame supporting a movable carriage having at least one ultrasonic detector assembly mounted thereon. Each ultrasonic detector assembly includes a bracket detachably mounted to the carriage, at least one holder movably coupled to the bracket, a spring-biasing mechanism to bias the holder from the bracket, a transducer shoe attached to the holder and a transducer attached to the shoe. The shoe is configured to conform to the outer surface of the billet and to be flooded with fluid to assist in testing.

Abstract: In a device for the arrangement of at least one ultrasonic testing head on a tube having a welding seam for the ultrasonic testing of the welding seam of the tube each ultrasonic testing head is built in a support. The support is provided with front and rear support points and led in constant radial distance to the tube on a test trace. The ultrasonic testing head is arranged in the area of the front support points, which are closest to the welding seam to be examined seen in the peripheral direction of the tube. A mechanical scanning device is provided, it is connected to the ultrasonic testing head and is arranged at the support in the area between the front and rear support points. The ultrasonic testing head has a single ultrasonic vibrator.

Abstract: Ultrasonography together with computer analysis tools are used to obtain measurements of gonadal density and size in male livestock, and particular in immunologically castrated boars in a slaughterhouse. These measurements are compared with reference thresholds with the main purpose of determining whether the immunologically castrated boars have entered puberty. Boars are likely to be subject to meat tainting subsequent to the onset of puberty due to biological secretions which occur at that time. This method allows the majority of tainted meat to be screened out prior to delivery.

Abstract: When an ultrasonic transducer for detecting flaws in metal plates or the wall of a metal cylinder is directed at a surface to be inspected at a particular angle, about ten percent of the signal will appear as Harris waves which propagate into the test plate at ninety degrees to the surface. This signal which propagates vertically is polarized, with the result that the signal has a greatly improved signal to noise ratio. For an incident medium of water and employing shear wave refracting in the medium of cast iron the specific angle is approximately 33 degrees from the vertical for best signal to noise ratio. For steel the specific angle is approximately 31 degrees and is about 50 degrees for brass. Shear or longitudinal waves can be employed to affect the detection of subsurface defects with the particular angle changing depending on the relation of the velocity of the sound waves in the refracting medium to the velocity of sound waves in the incident medium.

Abstract: A process and an apparatus for the ultrasonic testing of a component accessible only through a gap, includes driving a carrier accommodating an ultrasonic testing head into an annular gap and bringing the ultrasonic testing head into a position of alignment with the component, for the purposes of repeated testing of components disposed in the poorly accessible gap. Subsequently, the ultrasonic testing head is driven out from the carrier approximately at right angles to the driving-in movement, and is brought into contact with the component. After completing the testing process, the ultrasonic testing head is driven once more into the carrier and brought into a position of alignment with the next component.

Abstract: An ultrasonic inspection system for determining the presence, location, and size of flaws in laminated structure such as an "I" stiffener in a single inspection cycle. The exemplary system includes an immersion tank, five (5) single probes, 188 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stringer. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stringer with respect to the position of the transducer. The position encoder is spring-loaded against the stringer.

Abstract: A mechanical contour follower is disclosed for maintaining a transducer ninety degrees to a workpiece surface, with respect to longitudinal and transverse axes of the workpiece surface, and for keeping the transducer at a constant distance from the workpiece surface during an ultrasound inspection of the workpiece (these conditions being referred to as keeping the transducer normal to the workpiece surface).

Abstract: A continuous nondestructive process for controlling the rails on a railway line by ultrasounds is carried out by the emission of ultrasounds at successively different points along the rail which are spaced apart by a measured value. For each echo, the acoustic distance between the point of emission and the point of reflection of the beam of ultrasounds is determined, and then a bidirectional map of the echoes is established by correlation. Finally, this echo map is compared to a mask having a window, of which the shape, the orientation and the dimensions are determined by the characteristic features of the rail to be examined and by the type of defect looked for, only those echoes which appear in this window being then taken into consideration.

Abstract: An inspection apparatus and associated method includes a sensor housing defining an internal cavity in which a sensor is at least partially disposed for inspecting the surface of a structural part and for detecting defects in the surface and the substructure of the part. The inspection apparatus includes a plurality of compliant fibers extending outwardly from a first end of the sensor housing and circumferentially about an opening defined by the first end of the sensor housing. The compliant fibers support the sensor housing above the surface of the part and maintain the sensor in a predetermined position relative to the surface of the part. The plurality of compliant fibers are adapted to flex laterally to accommodate obstructions on the surface of the part, such as raised fasteners, doublers or lap joints while maintaining the sensor in the predetermined position relative to the surface of the part.

Abstract: Ultrasonic wave converged by an acoustic lens is made incident onto a sample and wave reflected from the sample is received and converted into received electric signal by a transducer. A part of this electric signal is picked up by a gate section and the signal thus picked up is applied to an attenuator where it is converted into a variable ratio of input to output. The strength of the signal thus gain-adjusted is compared with a threshold value by a comparator. Responsive to the comparison result thus obtained, the gain of the attenuator is adjusted to make the input/output ratio of the attenuator a desired value. A computer calculates the focus position of the acoustic lens from a gain curve of the attenuator changing when the acoustic lens is moved from a position, remote enough from its focus position, to the sample. Drivel signal responsive to the result thus calculated is applied to a Z-drive control section.

Abstract: A transfer device an ultrasonic sensor having an oscillating section for oscillating an ultrasonic beam toward wafers which are horizontally arranged in a carrier and a receiving section for receiving a reflected ultrasonic wave, and driving mechanism for vertically moving the ultrasonic sensor relative to the carrier so as to sequentially radiate an ultrasonic beam to the end faces of the wafers. The presence/absence of a wafer and projection of the wafer in and from the carrier are detected based on the reflected wave received by the receiving section.

Abstract: The invention is a compact ultrasonic tester involving rotating sensors The processor rotates with the sensors so that the output signal of the processor goes through the slip rings, rather than the output signal of the sensors. A spraying system is incorporated in conjunction with rollers. The rollers take the applied spray on the pipe surface and paint a film on the outer pipe surface to allow a good contact for meaningful results. A floating shoe is provided for holding each sensor against the pipe wall. The sensors are biased into contact with the pipe surface and the machine can handle different diameters of pipe. By controlling the pipe speed of advance and the rotational speed or the sensors, 100 percent coverage of the pipe wall is assured. The machine is compact and can be installed behind existing electromagnetic/gamma testers without major modifications to pipe-testing facilities.