Weld Investigation of Nuclear Power Plant Pressure Vessels

Abstract

Welds in nuclear power plant pressure vessels, which were in accordance with the ASME Boiler and Pressure Vessel Code, though not with some other codes, were investigated nondestructively over a long period of service. The results indicate that the vessels have been operating for many years, with large slag inclusions that do not extend to the weld surfaces, causing no damage to the vessels. Hence, the practical relaxation of excessively conservative acceptance standards is discussed.