A device for examining x-ray chi circular welds of lines of tubes

摘要

887,196. Pipeline testing. GELSENBERG BENZIN A.G. July 8, 1958 [July 8, 1957], No. 21917/58. Class 40(3). In apparatus for testing a pipeline formed of pipe elements welded end to end and in which a photographic film arranged around the periphery of each weld is exposed to radiation from a radio-active isotopic source supported on a carriage within the pipeline, the position of the source within the pipeline is determined by calibrated tape. An isotope 3, e.g. Iridium 192, is supported by the conical ends 8 of lead plugs 7 mounted in a carrier tube 12. Bushings 17 and 18 at the outlet and inlet ends respectively of the carrier tube carry pistons 19 and 20 comprising soft rubber cup-shaped discs 21 supported against sheet metal discs 22. The metal discs also support roller assemblies 24 and 25 by means of radially extending leaf springs 23 which maintain the radio-active source at the axis of pipeline 1. A tape 31 is attached at 30 to a swinging arm 29, pivoted about the inlet end 16 of the carrier tube, and passes via reversing pulleys 32 and 33 at the inlet end of the pipeline and eyes 39 to a reel 34 disposed at the outlet end of the pipeline. The inlet end is sealed by means of a clip 40 and a tubular attachment 43 covered by a plate 47. The carriage is driven along the pipeline by compressed air applied at a union 49 controlled by a throttle valve 48: In operation each welded seam 5 is surrounded by a photographic film 6, the tape is unwound over the length of the pipeline and clamped at the upper rim of the pipeline inlet. The external position of each joint is marked on the tape and the tape is then attached to the swinging arm 29. The carriage is driven along the pipeline until the first mark registers at the pulley 33, the drive is removed and after an exposure period of 3 minutes the carriage is driven on until the next mark registers. The quality of each weld is determined from its associated: exposed film.