Siemens STC-SH Compressor Series

Robust and Dependable

Siemens single-shaft centrifugal compressors with horizontally split casings in the STC-SH series can be used for the majority of process applications. Appropriate for process requirements such as medium pressures for a wide range of volume flows, the Siemens STC-SH is the preferred compressor for e. g. cracked gas, coker gas, process air or carbon dioxide.

The Siemens STC-SH is also available with an overhung impeller – a lower-cost alternative design for large volume applications especially with steam turbine drive.

Designed in accordance with API 617, this product line corresponds with all technical requirements imposed by the market.

With the integration of Siemens Turbomachinery Equipment, the Siemens STC-SH series was extended and now even covers chlorine applications.


  • The perfect match for most process applications, especially for toxic and inflammable gases, contaminated gases and low-temperature services
  • Flexible design concept combines custom-tailored design with standardized components for maximum reliability
  • Easy access to compressor internals


  • Petrochemical plants
  • Olefin plants
  • Refineries
    • Wet gas
    • Coker gas
  • Fertilizers
  • General chemicals
    • Dry chlorine gas
  • Oil & Gas Industry (on- / offshore); e. g. compression solutions for:
    • Natural Gas (e.g. gas transmission / gas pipelines)
    • Liquefied Natural Gas (LNG)
    • FPSOs
    • Boil-Off Gas (BOG)
    • End Flash Gas (EFG)
    • Fluid Catalytic Cracking (FCC) / wet gas
    • Sour Gas (Gas Gathering and Gas / Oil Separation)

Design Concept

The design concept of Siemens STC-SH compressors is very flexible, allowing easy adaptation to the requirements of specific process applications (e.g. gas or water injection).

Casings are mostly fabricated, but can also be cast for special applications (e. g. low-temperature applications down to -163° C / – 261° F). Impellers and stator parts (e. g. return vanes) are tailor-made and 100 percent machined, thus ensuring high aerodynamic predictability. The horizontally split casing permits easy access to all compressor internals by simply removing the upper half of the casing.
These centrifugal compressors can be equipped with up to ten impellers per casing and each casing can contain as much as four process stages. Designs include straight-through, double-flow and back-to-back configurations. A well-proven, fully parametric aerodynamic design, based on comprehensive in-house research and development, allows for the perfect matching of compressor performance and rotor dynamics for any application. Compressors of the Siemens STC-SH series are project-specifically designed to meet individual customer needs.

Besides conventional oil-lubricated tilting pad bearings, active magnetic bearings can be used, allowing 100 percent oil-free operation of compression trains in combination with electric motors, which are available also with magnetic bearings.


  • The first impeller of each process stage can be equipped with adjustable inlet guide vanes (IGV) allowing additional throughput and optimum turndown with maintained high efficiency
  • Dry gas seals, whether single, double or tandem, are used as standard as shaft end seals
  • Up to four process stages per casing
  • Up to ten impellers per casing
  • Intercooling and sidestreams
  • Easy access to internals
  • Active magnetic bearings as a referenced option

Control Systems
Perfect protection and process control via flexible Siemens control systems:

  • Anti-surge protection
  • Performance controllers acting on mass flow, suction or discharge pressure
  • Controlled by either IGV control, suction or discharge throttling, bypass operation or speed variation, thus operation with all available drive systems, i. e. electric motors, steam and gas turbines
  • Fully or semi-automatic start-up and shutdown sequences exactly matched to your process demands
  • Certified safety systems available
  • Local and remote control
  • Load-sharing controller for parallel trains


  • Compresses a comprehensive range of process gases
  • The tailor-made solution for individual customer specifications
  • Robust and dependable compressor design
  • Easy maintenance