Application-Specific Designs
Telescopic hydraulic cylinders utilize multiple nested stages.  These achieve a long working stroke in compact/retracted form.  Aggressive Hydraulics engineers application-specific designs to ensure that you get the proper cylinder for your application.

Common Types of Telescopic Cylinders:

  • Single-acting cylinders
  • Double-acting cylinders
  • Combination of Single- and Double-acting

Features & Specifications

  • Single and Double Acting Telescopic Types
  • Common hydraulic pressures up to 2,000 psi, special applications optional up to 3,000 psi
  • Max bore size available up to 15″
  • Min stage size available down to 3/4″
  • Common stroke lengths up to 500″
  • Number of stages common up to 5

Single-Acting Telescopic Cylinders

  • Single-acting cylinders use hydraulic pressure to extend, and retract due to load from gravity or some other external force.
  • Hydraulic flow and pressure extends the cylinder
  • Gravity or some other external force will retract the cylinder
  • Holds position
  • Long stroke in a compact closed length
  • Larger outer diameter than rod cylinders
  • Less complex design than double acting

Double-Acting Telescopic Cylinders

  • Double-acting cylinders use hydraulic force for both extension and retraction.
  • Hydraulic power retracts cylinder as opposed to gravity/force
  • Retract force is able to pull load
  • Conventional telescopic cylinders
    • Both ports located on rod end
    • Piston seals are typically cast iron rings
    • Cylinder is not designed to hold load in exact positions (drifting)
    • Minimum flow required to prevent stalling
  • Special features can be designed into telescopic cylinders
    • Both ports on the barrel design avoids moving hoses and wear patterns
    • Positive piston seals allow cylinder to hold the load and eliminate the minimum flow requirement
    • Less dead lengths per stage than a conventional double acting telescopic

Partially Double-Acting

Partially double-acting cylinders are typically used in over-center applications. These cylinders will provide retract force for a portion of the stroke, and gravity completes the retract cycle.

  • Plunger rod can be double acting and sleeves single acting.
  • Largest sleeve can be double acting and balance of sleeves and plunger rod single acting.
  • Skip-a-sleeve option, which is a sleeve or stage is skipped during design, thus increasing effective area and retract force.