The hydraulic expansion Shaft is a keyless shaft-hub connection device that utilizes hydraulic technology to generate clamping force. Through the precise expansion of an internal high-pressure oil chamber, it creates immense contact pressure and friction between the shaft and components such as gears,pulleys,couplings, or cutter heads, enabling high-precision and high-torque power transmission. As a superior alternative to traditional keyway and pin connections, it serves as a critical component in modern high-end equipment manufacturing.

lCore Advantages and Features

1.         Keyless Connection, Zero Stress Concentration: Eliminates stress concentration points caused by keyway machining, significantly enhancing the fatigue strength and service life of both the shaft and the workpiece.
2.         Exceptional Alignment and Ultra-High Precision: Achieves a centering accuracy within 0.005mm, ensuring smooth transmission, reducing vibration and noise, and making it ideal for high-speed precision applications.
3.         High Load-Bearing Capacity: The large contact area and evenly distributed friction enable the transmission of extremely high torque and axial forces.
4.         Easy Installation and Removal, Doubled Efficiency: Hydraulic tools allow quick tightening and loosening, completing operations within minutes, greatly reducing installation and replacement time while lowering labor intensity.
5.         Long Service Life, Simple Maintenance: Critical components are made of high-strength alloy steel for durability. The reliable sealing system requires only periodic checks of the hydraulic interface.
6.         Versatility: A single expansion sleeve can adapt to multiple workpiece bore specifications, offering strong compatibility and reducing spare parts inventory.
7.        Overload Protection: Under extreme overload conditions, slight slippage may occur, providing a degree of protection for the transmission system.

lHow to use

  uPreparation

1.          Cleaning: Thoroughly clean the shaft mounting area, the inner bore of the workpiece, and the inner and outer surfaces of the expansion shaft. Ensure that no dirt, burrs, dust, or oil stains remain. This is a critical step to guarantee precision and prevent damage.
2.          Inspection: Check the expansion shaft, sealing rings, and hydraulic accessories for any visible damage.
3.          Positioning: Gently push the workpiece (e.g., gear) to the predetermined mounting position on the shaft.

  uInstallation and Expansion (Tightening) Steps

1.         Insert the Expansion Sleeve: Gently push the hydraulic expansion shaft into the hub bore of the workpiece (e.g., gear) from the shaft end, ensuring it is positioned as designed.
2.         Connect the Hydraulic Pump: Securely connect the quick-release coupling of the manual or electric hydraulic pump to the hydraulic interface of the expansion shaft. Ensure the connection is clean and tightly locked.
3.         Begin Pressurization: Slowly pump the hydraulic pump handle to inject hydraulic oil into the expansion shaft
4.         Observe the Pressure Gauge: The pressure will rise steadily, and the expansion shaft will begin to expand uniformly, simultaneously gripping the shaft and the workpiece hub bore.
5.         Continue Pressurization to Recommended Value: Continue increasing the pressure to the recommended working pressure (refer to the product label or technical parameter table). Do not exceed the maximum pressure!
6.          Stabilize and Secure: After reaching the working pressure, maintain the pressure for a short period (approximately 1-2 minutes) to compensate for potential oil temperature changes and system relaxation, ensuring a stable clamping force.
7.          Depressurize and Disconnect:Slowly open the pressure relief valve of the hydraulic pump to fully release the system pressure to zero. After the pressure returns to zero, disconnect and remove the quick-release coupling of the hydraulic pump.

              Note: At this point, the expansion shaft remains in the tightened state, and the work piece is securely fixed.

              Installation Complete: The subsequent operations can now be performed, and the equipment is ready for operation.

  uDismantling and Unloading (Contraction) Steps

1.          Ensure Safety and Shutdown: Ensure the equipment is completely stopped and the power supply is disconnected.
2.          Connect the Hydraulic Pump: Reconnect the hydraulic pump coupling to the hydraulic interface of the expansion sleeve.
3.          Apply Minimal Pressure: Very slowly pump the handle to apply an extremely low pressure (typically 5%-10% of the recommended working pressure, e.g., 5-15 MPa). A     faint  "click" sound will be heard, indicating the release of the contraction seal.
4.          Critical: The pressure at this step is minimal, intended only to break the contraction seal, not to re-tighten the expansion sleeve. Excessive pressure may damage the   expansion  sleeve.
5.          Fully Depressurize: Once loosening is detected, immediately open the pressure relief valve to reduce the pressure to zero. The expansion shaft is now fully relaxed.
6.          Remove the Workpiece: The workpiece can now be easily slid off the shaft.
7.          Remove the Expansion Sleeve: Take the relaxed expansion sleeve off the shaft and store it properly.