Select Page

On hydraulic excavators, the boom and arm cylinder assemblies control the movement of the boom arm and stick arm. These important components utilize pressurized hydraulic fluid to generate linear motion, enabling the excavator to perform digging, lifting, and loading tasks.


Boom and arm cylinder assemblies are responsible for controlling the movements of an excavator’s boom arm and stick arm respectively. They convert hydraulic pressure into the linear motion needed to raise, lower and rotate these structures. Meanwhile, China hydraulic boom cylinder assembly factory provide quality cylinders and so that customers choose.

Understanding about the cylinder assemblies consist

The cylinder assemblies consist of the cylinder body, piston rod, cylinder eyes, seals, fittings and hydraulic hoses. When hydraulic pressure is applied, the piston rod extends or retracts from the cylinder body. This motion is transferred to pivot and maneuver the boom and stick arms as needed for operation.

Boom cylinders connect the excavator base to the boom arm, controlling the boom elevation. Arm cylinders join the boom and stick arm, managing rotation and extension of the stick. Most excavators have two arm cylinders, one on each side.

There are several cylinder types used in these applications:

  • Single-acting cylinders that only extend under pressure
  • Double-acting cylinders that can extend and retract
  • Rod-side cylinders with hydraulic ports on the rod end
  • Blind-side cylinders with hydraulic ports on the cylinder body
  • Welded-eye cylinders for heavy duty use
  • Pinned-eye cylinders for easier installation

The right boom and arm cylinder assemblies are critical for optimal excavator performance and longevity. Proper sizing and selection from reputable manufacturers is key. High quality hydraulic cylinder assemblies precisely control boom and stick movements, enabling smooth and efficient operation. By understanding cylinder types and components, owners can choose assemblies suited for their excavators’ size and working conditions. With robust cylinder assemblies, excavators can take on demanding jobs and keep working productively.