Penstock Codes—U.S. and Foreign Practice

Penstock design and construction in the United States have been guided to a large extent by the ASME Code for Unfired Pressure Vessels. At the same time, the penstock practice often deviates from the latter, particularly in the critical area of the allowable working stresses. As a result, safety standards in penstock design in the United States are far from being uniform. A study of three foreign penstock codes brings out certain advantages of separate design standards for this specialized field. It also suggests the use of higher allowable working stresses in penstocks than those permitted by the ASME Code. The contents of the foreign codes are listed and their more important aspects reviewed. Action by the ASCE toward creation of a uniform set of recommended rules for design and construction of penstocks in the United States is proposed.