Device for the panoramic radiography of weldings in metal pipings

Claim 1

Apparatus for radiographing welds from the inside of a pipeline comprising: (a) carriage means including a two wheel drive system arranged to propel the carriage means inside the pipeline; two wheel means for steering and maintaining the travel of the carriage on the bottom of the pipeline; (b) a radiography source; a safety, radiation impervious housing for said radiography source including first and second shield diaphragms defining a 360° panoramic exposition zone transversely to the pipeline; a spring loaded electromagnet for reciprocally moving the radiography source axially between said diaphragms for exposition and the safety housing, the spring loaded electromagnet normally biasing the source to a safety position within the safety housing; (c) means mounted on said carriage means for selectively stopping the carriage at a location to be radiographed including a GM counter positioned to receive radiation from a source located outside the pipeline at said location; circuit means operatively coupled to the GM counter to receive a signal input therefrom including a programmer for energizing said source electromagnet, said circuit means including means for terminating power to said drive means to stop the carriage, and energizing the programmer, said programmer being operatively coupled to energize a pulsating acoustical alarm for a predetermined period prior to energizing said source electromagnet.