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Heater-Treaters - Fabrication Services


TransTech delivers custom engineered and fabricated ASME heater-treaters for effectively removing water and sediment from large volumes of crude oil, when first-line separators fail to fully separate oil-water emulsions.

By utilizing mechanical separation methods in conjunction with the application of heat, heater-treater vessels facilitate oil/water separation and simultaneously reduce paraffin and other production stream impurities as necessary to prepare crude oil for delivery.

TransTech stands ready to address your most challenging separation challenges, including the design of units for colder climates and in cases where slugging may be a risk.  Our field service teams also have the expertise to evaluate and diagnose existing VRT operations, when desired results are not being met. 


Functionally, heater-treaters operate in a fashion that is fairly similar to other three-phase separators.  Oil/water emulsion enters the heater-treater vessel via a vessel inlet.  As the emulsion enters the vessel, an inlet diverter promotes initial separation.   Separated gas is immediately vented while any associated free water will fall to the bottom of the vessel where it is collected and drained away. 

Remaining emulsion then flows into a heating section containing fire tubes immersed in water, or at times oil, which serves to indirectly heat the emulsion to specified temperatures. 

It is the utilization of heat during the separation process that primarily distinguishes heater-treaters from other three-phase separators. The application of heat lowers the viscosity of oil, promoting oil/water separation and boosting the coalescing of water droplets. 

In some cases, heater-treaters are also fitted with an excelsior section, which acts as a filter for the further removal of impurities from the crude oil. 

Final clean oil exits the top of the vessel, while water is drawn off at the bottom.


Vertical and horizontal heater-treaters operate according to the same principals however, due to their upright position, vertical vessels can be installed on a smaller footprintand offer an ideal solution when well pad space is limited.  It’s important to note that vertical heater-treaters support a smaller treating area than horizontal vessels and therefore do not allow for the lengthier settling time (‘residence time’) often necessary to separate heavier crudes.


Horizontal heater-treaters are cylindrical bullet vessels with horizontal orientation, requiring a larger footprint on your well pad, but offering significantly more treating capacity than vertical vessels.  The additional treating area afforded by horizontal vessels allows for the residence time typically needed for processing heavier crudes. 

We design and build heater-treater vessels in both vertical and horizontal orientations, customized to meet your specific operating demands.


  • Efficiently treat large volumes of crude oil
  • Manage heavy and lighter grade crudes
  • Optimize separation
  • Minimize BS&W (basic sediment & water) 
  • Pressure ratings from 50 PSI to 250 PSI
  • Control liquids carryover 
  • Optimize the removal of impurities
  • Reduce and eliminate damaging paraffin & asphaltenes 
  • Customize units for any production requirements
  • Built to the latest ASME standards


  • Removable water or oil-immersed fire tubes 
  • Inlet diverter
  • Liquid gauges
  • Pre-heat system 
  • Temperature controller
  • High-temperature automatic shut-down
  • Pressure gauge
  • Vessel internals options
  • Vane demister
  • Valving & instrumentation
  • Controls
  • Oil & water dump valves or siphon
  • Oil & water liquid level controllers
  • Fuel gas scrubber
  • Skid-mounted 


  • Single- and multi-well designs
  • Horizontal or vertical orientation
  • Hay/excelsior section
  • Cold weather enclosures
  • Electrostatic grids
  • Specialty coatings
  • Insulation
  • Platforms & ladders
  • Liquid shut-off
  • Valving & instrumentation
  • Automation & control options
  • Safety features
  • Installation, startup & commissioning


Contact our ASME fabrication experts today to discuss your heater-treater needs at: 1-888-206-4563 —or click to contact us below:

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