Abstract: The defect detection system of the present invention includes an encircling coil for providing a saturating DC magnetic fields to tubular goods. Also included is an encircling drive coil for applying a low level AC field using three-phase AC. Encircling pick up coils within the AC drive coils detect uniform, time varying magnetic fields to reveal defects within the tubular goods passing through the system.

Abstract: A test apparatus 10 for testing the diameter of oilfield tubulars having various nominal diameters includes a machine frame 12 for successively receiving the axially movable tubulars, and upper and lower radially opposing carriages 16 and 18 each movable relative to the machine frame. First and second light generating sources 24 and 26 are each mounted on a respective carriage and transmit a wide light beam directed to intersect radially opposing sides in the oilfield tubular, such that the width of each light beams is reduced by engagement with the tubular. First and second light detectors 28 and 30 are each mounted on the carriages and are positioned for detecting the position of the reduced width light beams relative to the carriages and generating test signals in response thereto. Computer 32 is provided for receiving test signals from the sensors and generating a tubular diameter test measurement in response thereto.

Abstract: A plurality of magnetic field members are provided, each for selectively generating a time-varying magnetic field for combination into a o time-varying composite longitudinal magnetic field with magnetic flux lines which are substantially aligned with the central longitudinal axis of the cylindrical ferromagnetic member. Additionally, a traverse magnetic field member is provided which selectively generates a time-varying traverse magnetic field with magnetic flux lines which are substantially traversed to the central longitudinal axis of the cylindrical ferromagnetic member. The plurality of magnetic field members and the traverse magnetic field member are maintained out of contact with the cylindrical ferromagnetic member. Magnetic particles are placed on selected portions of the cylindrical ferromagnetic member. A time-varying composite longitudinal magnetic field and a time-varying traverse magnetic field are applied to the cylindrical magnetic member, while it is being rotated.

Abstract: The apparatus of the present invention is a machine for feeding, indexing, testing, and storing tubular goods. The machine concentrates on the end segments of the tubular goods. The machine uses the eddy current test method to test the outer surface, the inner surface, and internal and external threads. The tests may be conducted simultaneously and at each end of the pipe. The pipe is spun during the examination so that the sensors of the inner and outer surfaces, when driven, trace a helical pattern on the pipe, and the thread sensor is driven along the thread by the rotational force applied to the pipe being tested.