Abstract: Method and apparatus for ultrasonic flaw inspection of non-rotating tubular goods. The apparatus includes a test head with circumferential arrays of transducers oriented for inspection for each of transverse, longitudinal and wall thickness defects, and the test head includes individual pulser and pre-amplifier arrays as sequentially controlled from a remotely disposed operator console. The console includes sequential signal processing circuitry for developing and displaying defect indications for the test specimen as it is moved longitudinally through the test head.

Abstract: A swiveling device for tensioning a pre-stress bar having a threaded end projecting from an end face of the element to be pre-stressed comprises a jack having a movable part attached to the bar and a fixed part bearing against the element. A first bearing plate is mounted on the end face of the element around the bar and includes an annular spherical cup surface. A swivel joint nut is threaded on the end of the bar and has a spherical ball part seated in the cup surface of the first bearing plate forming a first swivel joint. A second bearing plate is slidably disposed on a face of the first bearing plate and includes a second annular spherical cup surface. The end of the fixed part of the jack proximate the element includes a spherical surface seated in the second annular spherical cup surface forming a second swivel joint.

Abstract: A method of measuring a contact stress at contacting surfaces of solid masses of a same kind or different kinds by utilizing an ultrasonic wave, including the steps of causing an ultrasonic wave to impinge onto the contacting surfaces; comparing an acoustic wave of the ultrasonic wave reflected from the contacting surfaces with an acoustic wave of the ultrasonic wave transmitted through the contacting surfaces (4); and measuring the contact stress using the value of the comparison as the index of evaluation, whereby measuring non-destructively, easily, quantitatively and with a high precision, the contact stress of the contacting surfaces of parts or members constituting, for example, a machine or equipment in their stationary as well as dynamic conditions.

Abstract: In an acoustic microscope device using an acoustic surface wave, a plurality of interdigital electrodes are provided on an acoustic surface wave propagating medium in a linear or circular manner, and these electrodes are selectively connected to a transmitting signal source via a multiplexer and respective delay lines having such delay times that the acoustic surface waves generated from the selected electrodes are focused at a focal point on the medium. The selection of the electrodes and the delay times of the delay lines are so changed that the focal point is moved two-dimensionally over the medium surface. The acoustic surface waves reflected at the focal points are received by the selected electrodes and electric signals from the electrodes are summed through the delay lines to derive an image signal at the relevant focal point. In this manner, a tomographic image of a specimen near its surface which is made in contact with the medium is formed.

Abstract: A novel test device particularly adaptable for simultaneously applying bending and torsion loads to whole bone specimens is provided, which comprises a substantially rigid support frame, first and second supports pivotally mounted to the frame for supporting the specimen therebetween, transverse loading (bending) means supported by the frame intermediate the supports for applying loads to the specimen at predetermined locations therealong, a torsion loading means supported on the frame for applying torque to said specimen by rotation of the second support, and force sensing means for measuring the bending and torsion loads and providing an output signal proportional thereto.

Abstract: A multi-axis force transducer capable of producing discrete output signals for forces and moments in each of three orthogonal directions is taught. Briefly stated, a base having three U shaped slots nested within each other are disposed inside a base or body. A series of holes through the base are placed parallel to the leg of the U-shaped slots with strain gages positioned therein thereby providing a plurality of beams. The body is relatively rigidly supported so as to allow free movement of the beams with an additional beam attached thereto to provide measurement capability for moments about one of the orthogonal axis. The strain gages are electrically interconnected so as to provide discrete output signals for forces and for moments in each of three orthogonal directions.

Abstract: A method and apparatus for detecting metal wipe damages of plane bearings with the metal wipe generating an ultrasonic signal as an acoustic emission signal when it occurs. The ultrasonic signal has a periodic appearance therefore, the metal wipe damages, can be detected by monitoring the periodic nature of the ultrasonic signal. The ultrasonic signal is received by a transducer fixed to the plane bearing with the periodic nature of the received ultrasonic signal being computed by a processing unit so as to provide a output signal of the occurrence of a metal wipe when the received ultrasonic signal is periodic.

Abstract: An inexpensive device which is easily operated to accurately measure the Coulomb parameters of the soil. The Coulomb parameters are used in Coulomb's equation to calculate the shearing stresses along a failure surface of the soil. The device includes an instrument to test soil shear strength to which several weights have been added. To obtain the Coulomb parameters, the instrument is placed on the soil to be tested and weights are incrementally added to it. The instrument is rotated at each weight increment and the shearing stresses are read from its calibrated dial. The stresses are plotted on a graph from which the Coulomb parameters are determined. The shearing stress of the soil with any known force applied to it can then be determined.

Abstract: A loading mechanism which may be moved relative to a free belt strand is provided with a measuring roller which is driven by the belt upon contact and furnished with pulse markers, and which, together with a pulse transducer sets to zero a device measuring the distance travelled by the loading mechanism, as soon as the measuring roller begins to rotate. The distance measured after a given period of contact of the loading mechanism acting with a known force is used as a measure for the belt tension.

Abstract: An electrodynamic instrument transformer head (10) for the non-destructive testing of materials by means of ultrasonics has a pole shoe (20) provided with exciting and receiving coils (14, 16), said pole shoe comprising a slotted end section (24) to prevent a formation of eddy currents. The end section (24) thereby is continuing into a basic body (22) preferably being made of a different material.

Abstract: A resonator force transducer assembly includes an elongate base element, a first arm disposed generally in parallel with a front portion of the base element, a first hinge joining the arm near a rear end thereof to the base element at about the middle thereof, an elongate resonator element such as a quartz crystal attached to the front ends of the arm and base element to extend therebetween, a second arm disposed generally in parallel with a rear portion of the base element, and a second hinge joining the second arm to the base element. A third hinge joins the front end of the second arm to the rear end of the first arm to form a type of compound lever arrangement so that when a force is applied to the second arm to urge it either toward or away from the base element, a portion of this force is transmitted via the third hinge to the first arm to urge it either away from or toward the base element to thereby stress the quartz resonator element.

Abstract: A material testing apparatus for testing physical properties of a test specimen includes an improved crosshead member adjustably supported on spaced vertical columns and adapted to support a grip for a test specimen to be loaded along a load axis. The improved crosshead member includes a load measuring (load cell) section defined by four spaced-apart openings located symmetrically with respect to the load axis. As shown there are two openings on each side of the load axis. The openings extend through the crosshead member. The crosshead is reduced in thickness or cross section between the openings to raise the stress levels in the crosshead so that strain gages are applied directly to the measuring section and can be used to measure the load applied to a test specimen.

Abstract: A variable speed machine for continuous testing of articles by use of processing air including: a shaft member rotatably supported on a frame and driven by a variable speed motor, a transfer wheel with a plurality of article holding pockets affixed to the shaft member, sealing apparatus mounted on the shaft member and associated with each article holding pocket and an extendable and retractable apparatus for sealingly engaging a portion of an article carried by an associated pocket during a testing period, pressurizing apparatus associated with the sealing apparatus for providing pressurized air to the seal and the test article, control valve apparatus for regulating the air pressure to the seal and the test article, shaft rotational speed monitoring apparatus providing a speed based signal and processing means for controlling operation of the control valve apparatus based on the speed based signal to provide an optimum air pressure to the sealing apparatus and associated test article.

Abstract: A method of measuring a characteristic of a material in a structure is the subject of the present invention. A known stress relationship S=TC/J is utilized in practicing the method of the present invention. In the foregoing formula S=strength in p.s.i.; T=torque force in pounds/inch; C=distance to the point of interest in inches; and J=.pi./2r.sup.4 where J is the polar moment of inertia for a circle of radius r (in inches). A drive head is adhesively secured to a segment of the structure to be tested. A known torque force is then applied to the drive head and this known force is translated into a measurement of the material characteristic utilizing the formula indicated. The method may be utilized to test the ultimate shear strength by failing the material or may be utilized to measure strength up to a design criteria without carrying the material to failure. Other material characteristics may also be measured utilizing the known formula set forth above and other known relationships.

Abstract: Ultrasonic wave attenuation is determined for a plurality of limited volumes of tissue comprising a body under examination by directing ultrasonic waves through each limited volume along a plurality of vectors, determining a measure of attenuation of the limited volume by detecting the frequency shift of reflections of the ultrasonic wave along each vector, and averaging the attenuation of each limited volume from each vector intersecting the limited volume.

Abstract: The ultrasonic wave attenuation of tissue undergoing examination is determined by directing a plurality of ultrasonic signals into the tissue, receiving and detecting a measure (e.g. zero crossings) of the frequencies of ultrasonic signals reflected from various depths in said tissue, and averaging the measures of the frequencies for each of the various depths. Attenuation of the tissue between a first depth and a second depth is determined from a comparison of the averaged measure at the first depth and the averaged measure at the second depth.

Abstract: Time gain control of a variable gain amplifier in an ultrasonic scanning system is defined from ultrasonic attenuation of tissue under examination. An ultrasonic signal is directed into the tissue and a reflected signal is detected. The frequency of the reflected signal is measured, and frequency dependent scatter perturbations are identified and eliminated from the measured frequency. Tissue attenuation is then established from the measured frequency after perturbations are eliminated.

Abstract: A device to permit easily preloading a grip used in specimen testing by providing load carrying links and means for stressing the links to a load level higher than that encountered during the normal loading of the grip, and providing mechanical compressive load carrying surfaces between the load applying member and the grip which are held in compression under the prestress load. Specifically, the link is formed as part of the piston rod in a hydraulic test system and a separate hydraulic chamber is subjected to pressure to load the link after which the grip can be hand threaded down into a metal surface to metal surface abutting relationship with the load applying member. Once the pressure is relieved in the auxiliary cylinder the full force of the stress in the link will hold the load applying member and the grip in contact.

Abstract: The image display in an ultrasonic scanning system is improved by compensating electrical signals representing reflections of ultrasonic waves at various distances from a transducer in accordance with the gain and sensitivity of the transducer to reflections at the various distances from the transducer. Gain represents a first order adjustment and sensitivity to change represents a second order adjustment.

Abstract: A roller-type ultrasonic inspection device for inspecting vehicle tires comprises a roller assembly 20 mounted on a non-rotatable hug 16. Two piezoelectric crystals 80,82 are mounted in the hub 16 such that their principal transmitting/receiving axes A and B converge generally radially outwardly of the hub. The angle between the axes A and B is selected such that when the roller assembly 20 is urged into rolling contact with the tread-bearing surface of a tire 90, the axes meet (allowing for refraction effects) in the body of the tire beneath the tread. This ensures that the device can detect defects in the body of the tire, and is relatively insensitive to the tread.