Indirect Fired Vessel : A vessel used to increase the temperature of a fluid by the transfer of heat from another fluid which is heated by a flame in the same vessel. The flame is contained within a fire tube or tubes. (RP 2G)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}