Abstract: An object detecting method and apparatus is disclosed and which operates by transmitting a wave toward an object embedded in a medium having a reflective coefficient at its surface, receiving the resultant reflected wave from the object, applying the received signal to a signal processing unit, and displaying the results of signal processing by the signal processing unit on a display unit.

Abstract: A chain-like self-moving robot includes three or more capsule units connected to one another in a string by means of couplers. By expanding and contracting intercapsule spaces in a predetermined sequence so that a smaller number of the capsules are moved while a larger number of capsules remain stationary, the chain-like robot can move forwardly or backwardly.

Abstract: A two-probe ultrasonic flaw detection apparatus, in which an ultrasonic wave is transmitted from a transmission probe into an object being inspected and ultrasonic waves reflected from a reflection surface in the object are received by a reception probe, operates to determine the position at which the combined intensity of ultrasonic waves reflected from each part of the reflection surface form a maximum. The reception probe is then moved to the position of maximum reception intensity. The position of maximum reception intensity is determined using as input parameters the ultrasonic characteristics of the object being inspected and of the transmission and reception probes, and the position of the transmission probe and the angle of incidence of the ultrasonic wave into the object.

Abstract: The surface of a specimen to be inspected is irradiated with a light having an intensity which varies from a position distant from the material, so that ultrasonic beams are generated in the material to be inspected. A coherent light is also projected onto a fixed surface provided at a given position and onto the surface of said material to be inspected. Vibration generated in the surface of said material due to ultrasonic beams reflected by a defect in the material, is detected in the form of change in phase of the coherent light that is reflected by the surface of the material. The change of difference in phase between the coherent light reflected by said fixed surface and the coherent light reflected by the surface of the material is measured with the lapse of time, in order to detect the flaw.

Abstract: An ultrasonic flaw detector driving apparatus with no guide rail and including a traveling member (2) capable of being freely mounted to and dismounted from piping (1) to be inspected, and a turning member (3) detachably attached to the traveling member for turning movement thereabout. The traveling member is equipped with a multiplicity of sets of traveling rolling elements (9,9a) maintained in contact with an outer peripheral surface of the piping and spaced apart from one another circumferentially of the piping while each set of the traveling rolling elements of comprises at least two rolling elements which are spaced apart from each other axially of the traveling member (2). The turning member (3) is equipped with at least one ultrasonic wave probe (4) which scans the outer peripheral surface of the piping to inspect it.

Abstract: A fluid composition suitable for use in drilling containing a sulfoethylcellulose alkali metal salt of which a degree of substitution is from 0.5 to 2.5 and the viscosity of a 1% by weight aqueous solution is 5 to 5,000 cP. The sulfoethylcellulose alkali metal salt has excellent water loss reducing ability and viscosity building ability and is soluble and stable in the presence of any monovalent and polyvalent salts at a wide pH range, and is applicable as a high molecular additive to a drilling mud and a completion fluid.

Abstract: A defect-responsive echo signal received by a transducer for transmitting and receiving an ultrasonic pulse beam is converted into a digital echo signal by an analog-to-digital converter. The amplitude of the digital echo signal is amended with compensation data stored in correspondence with lapsed times after the ultrasonic pulse beam has been transmitted from the transducer, and an amended echo signal is delivered. The amended echo signal is applied to maximum amplitude value-memory means. First decision means compares a stored value m of the memory means and the amended echo signal delivered anew n.sub.i, and alters the stored value of the memory means to n.sub.i when n.sub.i >m holds. Second decision means compares a value m' obtained by attenuating the value m and the value n.sub.i, and delivers the stored value m of the memory means as the peak value of the defect-responsive echo when n.sub.i <m' holds and besides n.sub.i <m holds.

Abstract: A digital type ultrasonic holography apparatus includes a clock generator for generating a clock pulse signal having a fixed period, a transducer for transmitting spike-like ultrasonic pulses toward an object in synchronism with trigger pulses derived through the frequency division of the clock pulse signal and receiving the reflected wave from the object, a waveform shaping circuit for shaping the received wave into a digital pulse signal, a coincidence detecting circuit for narrowing the pulse width of the digital pulse signal to a magnitude shorter than the period of the clock pulse signal and judging whether or not the pulse width-narrowed digital pulse is present at the level-changing time of the clock pulse signal, thereby to generate a coincidence signal, a scanner for scanning the transducer, and a device for displaying a hologram of the object in accordance with the value of the coincidence signal and the scanning of the transducer.

Abstract: To provide an improved holographic operation, a digital type ultrasonic holography apparatus is provided utilizing a clock pulse generator having a predetermined periodicity, an ultrasonic pulse beam generator for directing an ultrasonic beam to an object for measurement in synchronism with said clock pulse, a reflected wave conversion unit for converting reflected ultrasonic pulse beams from said object for measurement into digital pulses, a time coincidence detector for detecting time coincidence between said clock pulse and said digital pulses contained in a predetermined gate period and producing as output a coincidence signal when they coincide with each other, a unit for moving an ultrasonic generating and receiving transducer included in said ultrasonic pulse beam generator to a desired position, and a display device for displaying the hologram of said object for measurement using said coincidence signal as a luminance signal and a position signal of said ultrasonic generating and receiving transducer