Expansion Turbines - Improving Plant Optimization

Integrally geared radial expanders

Integrally geared radial expanders are applied where energy can be recovered from medium to high temperature off-gas or process gas streams from chemical and other industrial processes. The design is based on our integrally geared centrifugal compressor concept invented more than 70 years ago.

Product Information

Integrally geared radial expanders

Energy in the hot gas stream is converted directly to mechanical energy which can then be used to drive a compressor or generator respectively. While improving the overall energy balance of the plant, this also saves operating expenses as well as capital cost because there is no need for additional heat exchangers and steam generation equipment otherwise required for heat transfer.


Radial expanders can be configured as stand-alone units with up to three expansion stages arranged around a central bull gear, or they can be integrated into the casing of an integrally geared compressor transferring power directly to the compressor bull gear by a pinion shaft. 

Package Options

Radial expanders can be integrated with the driven equipment and auxiliaries into easy to handle packages for ease of on-site installation and commissioning.  Packages would normally include the compressor, its driver(s), process gas coolers, lube oil system, process piping, and other auxiliaries. Additional drivers can be electric motors as well as steam turbines. 


  • Purified terephthalic acid (PTA)
  • Dimethyl terephthalate (DMT)
  • Nitric acid
  • Other industrial processes 


  • Designed according to both API 617 and API 672
  • Gas inlet temperature: up to 550 °C / 1,020 °F
  • Maximum inlet pressure: 20 bar / 290 psi
  • Discharge volumes: up to 600,000 m³/h / 340,000 cfm
  • Power recovery: up to 45,000 kW / 60,000 HP
  • Up to three expansion stages in stand-alone configuration
  • Inter-heating between expansion stages possible