A study of the limit pressures of thick-walled pipes with part-through slots on the outside surface

An experimental study of the limit pressures of thick-walled pipes with part-through slots on the outside surface has been carried out. Three types of slots were tested on two groups of thick-walled pipes made of carbon steel. The postulated yield pressure is based on the inflexion point of the tangential strain vs pressure curve. Two geometric parameters combining the slot geometry and the pipe dimensions are proposed. The relative reductions in yield pressure caused by the slots are correlated with those geometric parameters. The correlations are reasonably good and empirical equations have been obtained. These equations can be used to estimate the reduction of yield pressure caused by slots on the outside surface of thick-walled pipes.