1 Scope
This document specifies the requirements for the procedures and design criteria used
for calculating the required wall thickness of new tubes and associated component
fittings for petroleum, petrochemical and natural gas industries. These procedures
are appropriate for designing tubes for service in both corrosive and non-corrosive
applications. These procedures have been developed specifically for the design of
refinery and related process-fired heater tubes (direct-fired, heat-absorbing tubes
within enclosures). These procedures are not intended to be used for the design of
external piping.
This document does not give recommendations for tube retirement thickness. A technique
for estimating the life remaining for a heater tube is described
This document is a supplement to API 530, 7th edition (2015) including addendum 1 and addendum 2, the requirements of which
are applicable with the exceptions specified in this document.