Abstract: In the ultrasonic inspection of test pieces, particularly tubular materials, a device for coupling a transducer to the surface of the test material, by a liquid medium, incorporates desirable features of both "contact" and "immersion" transducers. Disclosed is a coupler the housing of which has a cavity having a water supply inlet and an air exhaust vent. Water flow into the cavity if so controlled as to initially purge air from the cavity to fill it with water, after which the water flow is at a carefully controlled rate effective to keep the cavity filled while supplying fresh water only to the extent necessary to make up for water leaking out through a narrow gap defined between the test piece and the face plate of the disclosed coupler. The water within the cavity provides a liquid couplant between the test piece and a transducer carried by a holder mounted in the cavity for precision adjustment.

Abstract: An ultrasonic flaw detecting apparatus of electronically scanning type comprises a plurality of ultrasonic vibrator elements disposed in an arcuate array, wherein groups of N vibrator elements arrayed in the circumferential direction of an object under test are sequentially changed over to one another on one-by-one base to thereby scan an object under test with ultrasonic beams. By controlling phases of pulse signals applied to the individual vibrator elements, a region of focus of the ultrasonic beams is set at a predetermined depth of the object under test. For reception, only the echoes reflected from a predetermined focal range are selectively extracted by providing corresponding window or gate means.

Abstract: A duct probe having a coaxial cable is provided to advance a microphone through an underground or other duct containing a cable in a pressurized sheath for sensing fluid leaks in the sheath. The coaxial cable is embedded in a resilient fiberglass rod of one-piece construction. The rod is sufficiently flexible so that it can be wound onto and unwound from a reel having a cage-like configuration. A stationary base is provided to rotatably mount the reel, and the base is provided with a length measuring device responsive to the movement of the duct probe as it is unwound from the reel so that the distance by which the duct probe penetrates a duct can be determined. At the outer end of the rod, a microphone is mounted for sensing the sounds caused by a fluid leak in the pressurized sheath in the duct.

Abstract: An improved electromagnetic acoustic transducer essentially which comprises supports located at both the ends of a core assembly, a plurality of ferrite members, a plurality of permanent magnets or electromagnets and a plurality of coils wound around the core assembly, said combination functioning to inspect for any defect in a tubing having a small diameter.

Abstract: Apparatus for testing strength of door frames, consisting of a sturdy set of relatively movable pressure plates made of a heavy gauge sheet metal, designed for easy insertion into the usual space between the door and frame jamb at a position directly above the area of the latch bolt, and an interconnecting drive mechanism to apply a balanced force between the door and the frame on the inside only. Energy to drive the mechanism is supplied by the operator, using an ordinary drive socket and torque wrench with a modified scale that provides a direct indication of the force generated at the pressure plates. Frame spreading is also read on another scale and indicates an inverse measure frame strength. Rotary motion from the wrench is converted to linear motion of the plates by means of a lever assembly which also multiplies the driving force to the high level required. This door frame tester provides the user with an accurate high strength means for non-destuctive testing of new and older door frames.

Abstract: Method and apparatus for maintaining parallel relationship between the working face of a sound transducer and a planar surface of a workpiece or object under examination by the transducer, and for measuring and adjusting the thickness of a layer of liquid located between the transducer and object. A calibrating method and circuit is also associated with the transducer. Included is the step of placing the working face of the transducer in a position that is adjacent to but spaced from a front planar surface of the object, and providing the layer of liquid between the two. The transducer is then energized such that sound energy is directed into and reflected from the object after passing through the layer of liquid, the sound energy reflected from the object being received at the working face of the transducer.

Abstract: A conventional ultrasonic B-scan image is converted into a volume backscatter image by accounting for four propagation effects: dispersion of transmitted energy, beam width and beam intensity variations, inhomogeneous attenuation of ultrasonic energy, and signals resulting from specular reflections at interfaces. These images are a two-dimensional map of backscatter efficiency, are independent of details of the measurement system, and are quantitative images of an intrinsic property of tissue and other materials.

Abstract: Integrity of acetylene cylinder filler material is accurately and easily determined by monitoring acoustic emission counts as a function of load and establishing the distinctive signature of faulty filler material.

Abstract: The process comprises the following steps: positioning of at least two pieces connected to one another by means of at least a rivet between a stop member and a pressure member disposed to facing contact with one another and movable towards one another; pressing said members toward one another in order to elastically compress them with a predetermined force, and measuring the variation of the length of said rivet which takes place as a result of the elastic deformation of said pieces.

Abstract: An extensometer readout circuit conditions a strain information signal, representing strain of a specimen being tested, in such a way that yield point measurements and final elongation measurements of such specimen may be concurrently obtained. The strain information signal is provided by subjecting the specimen to a tensile or compression test by any conventional means known in the prior art. The strain information signal is first applied to a preamplifier. The preamplified strain information signal is then concurrently applied to both a high gain amplifier and a low gain amplifier. The signal obtained from the high gain amplifier is used for performing modulus calculations and for obtaining yield point measurements. The signal obtained from the low gain amplifier is used to obtain the total elongation measurement.

Abstract: The characteristics of an ultrasonic scanning system, including band-width, center frequency, and spectrum shape of reflected signals, are determined by directing ultrasonic energy from the system into a phantom having known ultrasonic attenuation and detecting the reflected ultrasonic signal for various depths in the phantom. Band-width is measured from the slope of frequency versus phantom depth. Center frequency is determined from the frequency of the signal reflected from the surface of the phantom. Spectrum shape is determined from the change in frequency of the reflected signal with change in phantom depth.

Abstract: A broadband angle-beam transducer system for producing and/or receiving Reigh waves on the surface of a metal medium comprising a thickness mode piezoelectric polymer transducer element embedded within and impedance matched to a plastic wedge. The transducer element is oriented at an angle determined to be the critical angle for Rayleigh waves in the metal structure to be tested. As a transmitter, the transducer element generates discrete dilatational wave pulses, one of which propagates within the plastic wedge to the plastic face in contact with the metal structure. At this face some of the wave energy is reflected as dilatational and shear waves within the wedge and the remainder of the wave energy passes through a coupling medium into the metal structure producing a Rayleigh wave traveling along the surface of the structure.

Abstract: The present invention relates to a process for producing a crack in a tube.The tube is placed in a groove made in a support, a load is applied by means of a plate disposed along a generatrix of the tube in order to start a crack and permit the propagation thereof. Load application is stopped when the crack has reached the desired dimensions.Application is to the production of faults having a controlled size in a tubular member.

Abstract: A hydrogen embrittlement tester, for a metal sample, has a vise device for holding the sample.For testing bend fracture, the distance between both ends of the sample is measured, which corresponds to that of the distance between the sample holding members. For testing the delayed fracture, the time from when the sample is held until it is fractured is measured.An electric path is formed between the sample holding members and the sample only when the sample is held so that measurement can be automatically stopped when the sample is fractured.

Abstract: Apparatus for picking-up and analyzing emitted accoustic and ultrasonic signals by means of a piezoelectric pick-up element connected to an amplifier with high input resistance, the output of the amplifier being connected for further evaluation to selective circuits and to an evaluation device. The piezoelectric pick-up element is situated in a casing, said casing being fixed to a hollow body being tested as by a strap encompassing at least partly both the casing and the tested hollow body.

Abstract: A method for localizing and analyzing sound emissions, wherein the position of the sound emission source is determined by incoming sound pulses at various measuring locations. The arrival time of a pulse or of a pulse characteristic is measured in three or more adjacent portions of each measuring location whose width is smaller than the expected sound field diameter. From this, the propagation time difference for the portion of each measuring location is determined and the sound arrival direction is determined from these propagation time difference values for each measuring location. Subsequently, the position of the sound emission source is determined from these direction values and the position coordinates of the measuring locations.The device for carrying out this method has three or more separate converter elements (1) for each receiver measurement head (E) whose total width is smaller than the expected sound field diameter.

Abstract: A method of insitu testing of soil compressibility comprises boring a hole in the soil to be tested, reconstituting the lateral stress environment in the soil adjacent the bottom of the borehole and then performing vertical compression tests directly on the undisturbed material at the bottom of the borehole. The testing apparatus of the invention includes a cylindrical container adapted to be pushed to the bottom of the borehole. An inflatable circumferential membrane around the exterior periphery of the container is inflated to reconstitute the lateral stress environment. The load may be applied to the base of the borehole by either a closed or inflatable fluid cell or directly by a flat or stepped load plate.In one embodiment of the invention, a thin-walled cylindrical tube penetrates the soil at the base of the borehole so as to laterally support the test soil for substantially one-dimensional vertical compression testing.

Abstract: The insonification apparatus is designed for the examination of an object, preferably for medical examinations. The apparatus contains an ultrasonic wave-generating transducer for emitting ultrasonic waves toward an examination plane, and an imaging device having principal planes for passing ultrasound waves received from the examination plane toward an imaging plane. The acoustic image formed in the imaging plane is received by a receiving transducer and transferred into electrical signals. The apparatus also contains an ultrasound condensing device such as a lens, a mirror, or a combination of such elements. This condensing device forms an ultrasonic image of the wave-generating transducer in the aperture of the imaging device. Thus, an increased uniformity of the intensity distribution in the image plane and an increased image contrast for high-spatial frequency information are obtained.

Abstract: A rotating scanner for use in ultrasonic echoscopy has a linearly scanned transducer arrangement, for transmitting beams of ultrasonic energy into an object (and receiving reflected ultrasonic echoes from the object). The transducer arrangement is rotated about an axis passing through the center or one end of the linear scan. The linear scanning may be mechanical scanning, or by electronic switching of an array of transducer elements.

Abstract: A rotary ultrasonic scan head includes a housing 10 consisting of generally symmetrical housing portions 10A and 10B having respective mating surfaces 14 and 16 that abut when the housing portions are assembled. A cavity is defined within the housing by recesses 18, 27, 34 and 38 in housing portion 10A and by complementary recesses 20, 28, 36 and 40 in housing portion 10B, by boot 50 disposed on the housing portions in assembly, and by pressure-compensating diaphragm member 42 disposed within the housing portions in assembly. A rotor 12 including a plurality of ultrasonic transducers 22, an impeller 24, and an optically encoded member 26 is supported for rotation within this cavity. An acoustic coupling and driving fluid is supplied to and withdrawn from the cavity through fluid inlet bore 68 and fluid outlet bore 70 in housing portion 10A, with the fluid entering the cavity being directed at impeller 24.