Control System for Combustion of Indirect Heating Furnace——Alternative cascade dual-cross limiting control system

The indirect heating system for the mandrel preheating furnace located at the Tube Rolling Division,Tianjin Steel Tube Co., Ltd. stayed with temperature delay between the furnace and the combustion chamber. With the newly developed control system described here in the paper, the alternative cascade dual-cross limiting control system, better adjustment characteristics have been obtained,thus the heating curve as required for the process and satisfactory effecfiveuess.