Water Bath Heaters

EPCM Holdings offers a variety of indirect heaters which are purposefully designed and fabricated. Our indirect water bath heaters are skid-mounted, factory-wired and piped to meet design criteria for specific client requirements.

Customized and Standardized Solutions

EPCM offers a custom-designed range of water bath heaters, tailored to the application, to ensure the medium (typically high-pressure natural gas) is reliably and safely heated to the necessary temperature to meet the downstream process requirements.

Standard capacity and size of indirect water bath heaters are tabulated below. The table is for reference purposes only, actual model number and size will depend on the process condition and other requirements. Standard heater sizes vary between 30 000 – 35 000 000 BTU/hr (10-10 000 kW).

Model NumberHeating CapacityVessel Size
kWMM BTU/hrDia (mm)Length (mm)
EWH – 10100.034502000
EWH – 25250.095003500
EWH – 50500.176003500
EWH – 75750.267503500
EWH – 1001000.347504500
EWH – 1251250.439004500
EWH – 1501500.519005000
EWH – 2002000.689006000
EWH – 2502500.8510006500
EWH – 3003001.0211006500
EWH – 4004001.3612506500
EWH – 5005001.7112508000
EWH – 6006002.0515008000
EWH – 7507502.5615009500
EWH – 1 00010003.4117509500
EWH – 1 50015005.1220009500
EWH – 2 00020006.82225010500
EWH – 2 50025008.53240011000
EWH – 3 000300010.24260011000
EWH – 4 000400013.65300011000
EWH – 6 000600020.47350012500
EWH – 7 500750025.59400012500
EWH – 9 000900030.71400014000
EWH – 10 0001000034.12400014000

EPCM offers customized design alternatives to meet client specifications and requirements. Contact us for assistance with a customized solution for your project needs: Contact page

Principle of Operation

EPCM’s indirect water bath heaters consist of a heater shell that contains a process coil and fire tube which is submerged in the heat transfer medium. The heater shell is commonly an atmospheric vessel designed and manufactured per API 12K requirements, or as a pressure vessel (ASME VIII), depending on client specifications. All designs can accommodate custom dimensions.

Depending on the heat transfer requirements, the fire tube (combustion chamber) design can feature single- or multiple tubes. In larger heaters, the fire tubes are designed to have multiple flue gas return pipes to optimize the heat transfer area and increase the overall system efficiency. The tubes are removable and designed to efficiently transfer heat into the surrounding heat transfer medium and minimize flue gas frictional losses. The fire tube is installed in the lower half of the heater shell, fully immersed in the water bath, to transfer the heat efficiently.

The fire tube transfers the heat released by the burner to the heat transfer medium, which then transfers the heat to the process fluid through the process coil. A temperature transmitter controls the burner to maintain the required bath temperature for both the inlet and outlet conditions.

We can design single or multiple burners depending on client requirements. Forced or natural draft burner designs are available depending on working conditions and power availability on site. Natural draft burners are popular for remote locations or locations with limited or no available power supply. Forced draft heaters are ideal whenever there is a low emission requirement while offering superior burner control compared to natural draft style heaters.

The main benefits of indirect heating are that the heat is transferred evenly, and the coil inside wall temperatures are lower than those of direct heaters – reducing scaling, coking and plugging. Indirect heaters are also safe due to the separation of the process stream from the combustion chamber and flue gasses. Indirect water bath heaters are widely applicable to the petroleum industry, power generation and industrial systems.

Heater shells are thermally insulated, while still ensuring access to the coils, burner/s or stack. Insulation materials are appropriately selected based on operating temperatures and climate conditions.

Safety, Health, Environmental and Quality

From within the EPCM Group of Companies, HSEQ assurance is provided from our Germany-based centre of excellence. Our team of experts specializes in machinery designs inclusive of water bath heaters. EPCM is fully accredited with ISO 9001; ISO 14001; ISO 45001 and ISO 3834. All our facilities and subsidiaries conform to the group’s systems and procedures, complying with industry best practices and international standards.

Design Codes and Standards

  • NACE
  • NFPA
  • API 12K
  • API 6A, API 6D
  • ASME Section VII
  • ASME B31.1
  • ASME B31.3
  • ASME B31.8

Design Features and Benefits

  • Advanced Control Systems
  • Fuel Source and Burner Flexibility
  • Custom Sizes
  • Simplified Maintenance – Easily Accessible and Removable Coils and Tubes
  • Economical – Efficient Design and Fuel Consumption
  • Large Turndown Ratio
  • Safe and Reliable

Typical Applications

  • Heating High-Pressure Natural Gas
  • Heating Crude Oil
  • Heating of Chemicals
  • Hydrate Prevention
  • Vaporizing and superheating of LPG and LNG

Types of Fuels

  • Natural Gas
  • LPG
  • Fuel Oil/Light Oil
  • HFO
  • Dual Fuel Burners

Heat Transfer Medium Types:

  • Water
  • Glycol
  • Thermal B

Typical Standard Features, Controls and Components:

  • Heater Shell, Removable Fire Tube and Process Coil
  • Exhaust Stack and Water Expansion Tanks
  • Burner Management System
  • High-Temperature Shutdown
  • Level Detection (Low-Level Hazard)
  • Insulation

Optional Features and Extras:

  • Dual Temperature Control
  • Electric Heating Element
  • VSD for Air Intake Control (Reduced Power Consumption)
  • Black Start Package
  • Functional Testing During FAT (Factory Acceptance Tests)
  • Skid-Mounted

Further Reading

From our blog:

For more information on our fabrication capabilities and facilities:

Key Projects

  • Tema LNG (involving Water Bath Heater capacity of 390 mmscfd)