Assessment of Fire Damage to Pressure Vessels in a Refinery Unit

A systematic approach is proposed to assess the fitness of pressure vessels in the alkylation unit of a refinery after fire damage. Techniques used to study a Jan. 11, 1991, fire included in-situ metallography; hardness testing; crack detection; and measurements of thicknesses, plumb, circumference, and straightness. Emphasis is placed not on conventional techniques such as hardness testing and in-situ metallography, but on methods of measuring the affected vessels and effectively detecting and sizing distortions caused by the fire. Though these methods have been available in the past, they are not used in typical fire damage assessments.