MICROSCOPY OF FAILURE MECHANISMS IN FILAMENT-WOUND PIPE

Filament-wound pipes pressurized in one of two modes, to give biaxial or uniaxial stress conditions, have been examined using standard microscopic techniques. Whitening of the pipes which develops during testing has been correlated with different types of cracking. A mechanism for weepage in filament wound pipes by the crossing of transverse cracks in adjacent laminae is described. The types of crack present in the pipe at loads up to final failure were found to be consistent with predictions of the stresses acting in the pipe walls. © 1979 Chapman and Hall Ltd.