Combustion Engineering, Incorporated, Single Furnace Natural Circulation Boiler for Ddg-15 Class

摘要

A Combustion Engineering single furnace integral superheater boiler, with accessories including automatic feedwater controls and air operated retractable superheater cavity soot blower, was evaluated to determine performance and general suitability for use on DDG-15 Class ships. Tests were conducted at steaming rates comparable to those of the ships for which the unit was designed to determine optimum return flow sprayer plates, burner performance, circulation characteristics, steam baffle efficiency, automatic feedwater regulator capabilities, superheater cavity retractable soot blower performance, and to evaluate the unit and its components under normal and emergency conditions. To correct performance deficiencies, refractory gas baffles were developed to increase superheater outlet temperature; additional screen tubes were installed to shield the superheater outlet pass and reduce tube metal temperatures in that pass; steam drum girth plates were modified to improve circulation; and minor improvements in the feedwater regulating valve and the superheater cavity retractable soot blower system were made. Following completion of all modifications the overall boiler performance was considered satisfactory. (Author)