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A new set of delayed coking units is being installed, and interlocks have been installed in the heating furnace section. Since we have no prior experience with process handling under interlock conditions, we are seeking advice from everyone! As a beginner, I don’t know how to upload images; therefore, I’m unable to share the logic diagram of the interlocks. The conditions that trigger these interlocks are as follows: (1) High temperatures are detected at the two smoke outlet points of the first independent furnace’s convection chamber; (2) High temperatures are detected at the two smoke outlet points of the second independent furnace’s convection chamber; (3) The emergency shutdown button is pressed; (4) High temperature is detected at the non-driving end of the heating furnace’s feed pump; (5) High temperature is detected at the non-driving end of the heating furnace’s feed pump again; (6) High temperature is detected at the stator of phase A of the heating furnace’s feed pump; (7) High temperature is detected at the stator of phase B of the heating furnace’s feed pump; (8) High temperature is detected at the stator of phase C of the heating furnace’s feed pump; (9) High temperature is detected at the inlet temperature of the air preheater; (10) High temperature is detected at the outlet temperature of the air preheater; (11) Low pressure is detected at the outlet of the blower; (12) High pressure is detected at the inlet of the flue gas extractor; (13) The manual shutdown button of the flue gas extractor is pressed; (14) Low flow rate is detected in the feed to the heating furnace; (15) Low pressure is detected in the fuel gas supply for channels 1–4 of the heating furnace; (16) Low pressure is detected in the fuel gas supply for the pilot lights in channels 1–4 of the heating furnace. The consequences of these interlocks are: (1) The flue gas dampers open; (2) The blower of the heating furnace stops operating; (3) The flue gas extractor of the heating furnace stops operating; (4) The radiation pumps stop operating; (5) The radiation control valves for channels 1–4 close; (6) The steam injection valves for channels 1–4 open; (7) The fuel gas valves for channels 1–4 close; (8) The pilot lights for channels 1–4 turn off; (9) The quick-opening doors of the heating furnace open