Can a Hydraulic Motor Be Powered by High Pressure Fluid from a Linear Actuator?

Yes, a hydraulic motor can be powered by high pressure fluid coming from a linear hydraulic actuator. This method has been implemented in various hydraulically operated systems, withstanding pressures up to 5000 psi (34.5 MPa) and providing long-lasting, tough, and reliable operations.

Applications and Considerations

The use of hydraulic motors alongside linear actuators is quite common in industrial and engineering applications. Typically, these systems operate at pressures such as 3000 psi (20.7 MPa) and 5000 psi, often utilizing servo-controlled Hydraulic Power Supplies (HPS).

It is important to note, however, that the fluid coming from a hydraulic actuator is limited and intermittent. This is due to the nature of the actuator, which uses a cylinder that performs a stroke with high pressure and then returns to a lower pressure state. While the actuator itself has minimal leakage, hydraulic motors, even new ones, often exhibit higher leakage rates. This leakage can affect the repeatability of the motor's shaft angle.

Details and Solutions

Specific requirements and details will greatly influence the feasibility and effectiveness of this approach. For accurate planning and implementation, one needs to consider several factors:

Leakage and Repeatability: Piston motors have the least leakage, followed by gear motors, and then centrifugal motors. Understanding the leakage characteristics is crucial for ensuring accurate operation. Recharge Mechanism: To handle the intermittent supply of high-pressure fluid, a recharge system is necessary. This can be achieved by either re-stroking the actuator after the motor stops or mechanically driving the motor to generate oil for the cylinder. Piston Accumulators: For high flow rate "spike" demands, piston accumulators charged with nitrogen-over-hydraulic oil can be used to manage fluctuations in pressure and flow.

Practical Implementation

Given the challenges, practical implementation requires a thorough understanding of the system's requirements. Here’s how one might approach the design:

Flow Rate Management: Determine the peak flow rates required by the hydraulic motor and ensure the actuator can provide them. Pressurization Control: Use a servo-controlled Hydraulic Power Supply (HPS) to maintain consistent pressure and optimize performance. Leakage Compensation: Implement a mechanism to compensate for any leaks in the hydraulic motors, ensuring consistent operation. Recharge Strategy: Develop a strategy for recharging the stroke of the actuator or driving the motor to generate oil for the cylinder.

Conclusion

While powering a hydraulic motor with high-pressure fluid from a linear actuator is possible, it involves careful planning and consideration of specific factors such as leakage rates and recharge mechanisms. By utilizing techniques such as piston accumulators and understanding the system's requirements, one can effectively implement this solution in various hydraulically operated systems.