| 摘要 |
1436101 Monitoring pipes electrically SNAMPROGETTI SpA 23 May 1974 [4 June 1973] 23204/72 Heading G1N Apparatus for monitoring the attitude of a pipe comprises a wheeled carriage 1, Fig. 1, driven through the pipe by a motor 3 energized via a cable (not shown) or a battery 5, and attached to a probe consisting of four extended arms 8, spring- biased so that the wheeled extremities 10 rest on the inner surface of the pipe. Each arm 8 is pivotted at 9 and carries a wire rope 13 attached through gears 12, 15 to the slider 16 of a potentiometer 17, Fig. 2, whereby a change in the internal diameter of the pipe produces a corresponding change in the voltage at the slide 16. The potentiometer 17 of each pair of diametrically opposite arms 8 are connected via oppositely poled diodes 18, 19 to an A.C. supply 20 and their sliders 16 are both joined to a conductor 21, whereby the potentiometers are energized alternately by positive and negative A.C. half-cycles to send alternate displacement signals through conductor 21 to a central station. Conductor 22 carries similar signals from the other pair of arms 8. An alarm is actuated when the displacement signals exceed a predetermined value. The carriage 1 also carries a pendulum type inclinometer 23, measuring on a potentiometer 28 the deviation of the axis of the pipe from horizontal, and a gyroscope 30, measuring on a potentiometer 32 the axial twist of the pipe about a vertical axis. The potentiometers 28, 32 are fed through diodes 29, 33 and the signals from sliders 27, 31 alternate along conductor 34. The position of the probe along the pipe is determined by counting pulses from a switch 35, 36, 37 on one wheel 11, which are superposed on conductor 34. The apparatus may be programmed to proceed along the pipe for a pre-set distance and then return. |
