Abstract: An improved pipeline caliper pig for providing a record of the deviations of the interior wall of a pipeline including a pig body assembly having a longitudinal axis and support members so that the pig body assembly is supported within a pipeline, the support members impeding the flow of fluid therepast so that the pig body is propelled by fluid flow along the interior of the pipeline, an integrator plate carried by the pig body assembly, arms extending from the pig body assembly for responding to deviations in the interior wall of the pipeline and coupling members to transfer the deviations to the integrator plate, a plurality of axially positionable shafts affixed at one end of the integrator plate, and electrical transducers at the other end of each shaft so that movement of the integrator plate relative to the pig body is transmitted into electrical signals, an orientation detection member and a signal receiver and recorder to record the electrical signals of the transducers and the orientation detection

Abstract: An improved pipeline caliper pig for providing a record of the deviations of the interior wall of a pipeline including a pig body assembly having a longitudinal axis and support members so that the pig body assembly is supported within a pipeline, the support members impeding the flow of fluid therepast so that the pig body is propelled by fluid flow along the pipeline interior, an integrator plate carried by the pig body assembly, arms extending from the pig body assembly for responding to deviations in the interior wall of the pipeline and coupling members to transfer the deviations to the integrator plate, a plurality of axially positionable shafts affixed at one end to the integrator plate, and electrical transducers at the other end of each shaft so that movement of the integrator plate relative to the pig body is transmitted into electrical signals, an orientation detection member and a signal receiver and recorder to record the electrical signals of the transducers and the orientation detection member

Abstract: A speed control for an AC motor varies the frequency and amplitude. The speed control includes a rectifier which converts the AC power supplied to negative and positive DC. A switch connects each power conductor leading to the motor with one of the DC voltages. The switches are switched on and off to provide alternately positive and negative voltage. Controls for the switches include an oscillator which provides pulses of frequency that can be varied. A binary counter counts the pulses from the oscillator and provides binary outputs. A memory unit provides a programmed output to the switches for each binary output received. In one embodiment, the amplitude is varied by comparing a triangular wave from the oscillator with the DC input level. Enabling pulses equal to the excess of the triangular wave over the DC input enable the memory unit. In another embodiment, the enabling pulses are provided to an amplitude switch which is cycled to vary the DC rail voltage.

Abstract: A motor control circuit for submersible pumps has features to prevent restarting while the electric motor is backspinning. The circuit includes a sensor for sensing the voltage produced by the residual magnetism in the rotor of the motor while it backspins. The voltage sensed is amplified, then rectified and compared with a reference voltage that is preset. The reference voltage corresponds to a voltage produced during backspinning at a selected maximum amount tolerable when restarting. The DC pulses are filtered to provide a corresponding voltage, then compared to the reference voltage. The control circuit is disabled from allowing a restart, either manual or automatic, when the corresponding voltage is greater than the reference voltage.