The National Shipbuilding Research Program. Tank Sealing With Coating Materials

Abstract : The purpose of the project was to improve productivity in ship tank tightness testing. To improve productivity new tank tightness testing methods which are easier faster and at least as reliable as the current hydrostatic method must he implemented. An earlier study conducted by SWRI entitled "Improved Tank Testing Methods" January l98O compared the standard hydro test to a number of other tightness testing methods. The study also performed a preliminary evaluation on how well ship tank coatings plug small pinhole-type flaws in tank boundaries. Results of this work found that (1) greater assurance of tank tightness is provided by a low pressure air and soap test than by a hydrostatic test (2) in a laboratory environment tank coatings can effectively seal flaws which are much larger than the minimum flaw size detectable by current tightness testing methods and (?) only ultrasonic detection methods show potential for improving productivity in ship tank testing.