Cylinder classification

The type of cylinder and the application in which it is used are two of the main criteria when selecting the appropriate seals and guides. Applications are referred to as light duty, medium duty or heavy duty applications. These classifications are somewhat subjective but the duty levels are typically characterized by the following criteria.

Light duty cylinders

Light duty cylinders, e.g. cylinders used for stationary equipment indoor in a factory environment, may be characterized by:
  • system pressures up to 160 bar (2 300 psi)
  • temperatures up to 70 °C (160 °F)
  • rare pressure peaks in excess of system pressure
  • minimal side loads acting on guides
  • environment with moderate temperature fluctuations and relatively free of contaminants

Medium duty cylinders

Medium duty cylinders, e.g. cylinders in agriculture off-highway equipment, may be characterized by:
  • system pressures up to 250 bar (3 625 psi)
  • temperatures up to 90 °C (195 °F)
  • moderate pressure peaks in excess of system pressure
  • moderate side loads acting on guides
  • environment with temperature fluctuations and typical external contaminants such as dust and moisture

Heavy duty cylinders

Heavy duty cylinders, e.g. cylinders in off-highway earthmoving or forestry equipment, may be characterized by:
  • system pressures of 400 bar (5 800 psi) or more
  • temperatures exceeding 90 °C (195 °F) with peaks in excess of 110 °C (230 °F)
  • regular pressure peaks in excess of system pressure
  • heavy side loads acting on guides, usually due to heavy components and/or high accelerations
  • tough environment with wide temperature fluctuations and typical harsh external contaminants
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