Fired heaters use the heat generated from fuel combustion to heat up process fluids contained in the coils of a heater vessel. A heater can be designed to a direct heating type where the process medium flowing in the heating coils is heated directly. For indirect heating, the heater heats up the Heat Transfer Medium (HTM) which is then circulated to heat up the process; like heating coils in the tank or providing heat source for a heat exchanger.


DFINITI’s fired heaters are designed and constructed according to industrial standards such as API 560 (ISO 13705) and DIN 4754.
Subject to design code, a fired heater system may have the following typical components:

  • Fuel system and air system
  • Fired Heater Chamber including Casing, Refractory Wall and Internal Support
  • Stack
  • Skid Structure, Platform
  • HTM Pumps
  • Burner and BMS
  • Heating Coils, Radiant and Convection
  • Instruments, PLC Control Cabinet
  • HTM Storage and Expansion Tanks


  • Crude oil transportation
  • Crude benzene refining
  • Methyl ethyl ketone (MEK)
  • Printing and dyeing
  • Textile
  • Engineering plastics
  • Resin
  • Organic Silicon
  • Pulp and paper
At DFINITI, we use industry recognised software to perform calculation and simulation for different parts and processes. The software in use include:
  • FRNC-5 software for fired heater simulation covering furnace, tube and transfer lines, etc.
  • STAAD software for 3D structural design and analysis
  • CAESAR II for pipe stress analysis
  • Other proprietary software for calorific value calculation
With extensive field experience, we offer turnkey solutions covering different project milestones to our customers. Our capabilities are as follows:
  • Design
  • Materials and Fabrication
  • Site Assembly Assistance
  • After-sales Support
  • Engineering
  • Inspection and Testing
  • Commissioning and Pre-commissioning

With customised robust design and modularised construction, DFINITI’s fired heaters deliver a safe, reliable and high efficiency performance in a cost-effective manner while complying with relevant environmental emission regulations.

POWERTypical 100kW ~ 54MW
FUELNatural Gas / Fuel Gas / Fuel Oil / Gas-oil Dual Fuel
DESIGN CODEAPI 560 (ISO 13705) / DIN 4754 / Others
INDUSTRIESOil and Gas Refinery, Petrochemical, Natural Gas, Chemical Plants, Waste Gas Treatment, Incineration
MATERIALS OF CONSTRUCTIONTubesCS, Cr-Mo, SS304(H), SS321(H), SS316/317(H), etc.
SupportCS, Cr-Mo, SS304H, SS309H, SS310H, etc.


Direct fired heaters are also referred to as furnaces in which the medium in the heater tubes gains heating energy directly from fire. Heat is transferred using radiant heat from a burner with convection section to provide heat recovery from flue gas. The governing standard for design and construction is typically API 560 (ISO 13705 identical). The primary heater components may include APH, fuel train, burner and BMS, heating tubes (radiant section and convection section), refractory wall, casing, stacks, control and electric cabinets and other accessories as required.

Indirect fired HTM heaters use fired fuel to heat up the HTM (heat transfer medium) and supply the heated HTM to the required process section to provide heat energy. Indirect fired HTM heaters share similar components with direct fired heaters, but they have extra modules such as storage tank, expansion tank and pump skid to store and circulate the HTM.



As compared to a direct fired heater which has a single process port-in/port-out connection, an indirect fired HTM heater creates a sustainable loop to power up individual heating needs from different process sections. The HTM(s) will ultimately be collected at one common point for re-heating. This offers more flexibility in process designs. The governing code for an indirect fired HTM heater is API 560 or DIN 4754.

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