Hydraulic cylinders differ both in their design and in their drive characteristics. Due to the wide variety of options, there is an optimal cylinder solution for almost any application. To make it easy to distinguish between the various solutions, at AHP they are assigned various number combinations. The most important of these are listed below.

Single acting:

  • 101: single-acting – retraction via external force
  • 102: single-acting – extension via external force 
  • 111: single-acting – retraction via an integrated spring
  • 112: single-acting – extension via an integrated spring


When the cylinder is retracted via an integrated spring, only the force for the return stroke is applied. External masses are not taken into account.
In practice this type of piston return of single acting cylinders is generally only relevant for short strokes.

Double acting:

  • 201: double-acting – non cushioned
  • 204: double-acting – forward and return stroke cushioned 
  • 206: double-acting – cushioned forward stroke
  • 208: double-acting – cushioned return stroke
  • 244: double-acting – linear cushioning on both sides 
  • 246: double-acting – linear cushioning front side 
  • 248: double-acting – linear cushioning rear side


Special designs:

  • 202: double acting for various media
    (consultation with AHP Merkle is necessary)



Not all operation modes are available for all cylinders. Additional options, and special design requirements are available upon request for each cylinder. Please contact us!