INVESTIGATION FOR CORROSION OF SUBMARINE PIPE

PURPOSE:To obtain an objective and exact investigation result by taking the X-ray transmission photograph of submarine pipe to be examined using submarine X-ray photographing techninque and measuring the depth of reduced thickness due to corrosion by means of the density of the photograph. CONSTITUTION:An X-ray film 4 is sandwiched between a scattered radiation eliminating grid 3 and a lead plate 5 and is attached to a part of a submarine pipe 2 to be examined via said grid 3. When X-ray from an X-ray device 1 irradiates the submarine pipe 2, the X-ray is attenuated in accordance with the thickness of the submarine pipe or a degree of its corrosion and reaches the X-ray film 4 through the scattered radiation eliminating grid 3. The X-ray film 4 is then sensitized to a degree corresponding to the amount of X-ray reaching it. In this case, the photographic density of the resultant X-ray transmission photograph is generally proportionate to the pipe thickness so that an objective and exact investigation result can be obtained from the photographic density, its change, its distribution and the like.