In hydraulic systems, precision control is vital to ensure both performance and longevity. One of the critical components in achieving smooth operation is the hydraulic cylinder cushion. Without proper cushioning (and in the absence of other speed controls), a cylinder could stop abruptly at the end of its stroke, creating potentially damaging mechanical stress. For applications where significant loads are involved, hydraulic cushions are essential to prevent sudden stops and ensure safety.
Why Do You Need Hydraulic Cylinder Cushions?
When a cylinder reaches the end of its stroke without a cushion, the momentum of the moving load can cause a sudden, jarring stop. This shock can lead to damage over time, especially in systems with high pressures or heavy loads. Cushioning mitigates this by controlling the flow of hydraulic fluid, allowing for a smooth deceleration as the cylinder nears the end of its stroke.
Beyond protecting the machinery, cylinder cushions are also a crucial safety feature, especially in applications like **aerial devices** where people are working on the equipment. In these scenarios, sudden stops can not only damage the equipment but also pose a serious risk to the operators. By providing a controlled deceleration, cushions help protect both the machine and the individuals using it, ensuring smoother operation and significantly reducing the risk of injury.
How Do Hydraulic Cylinder Cushions Work?
Hydraulic cylinder cushions work by restricting the flow of hydraulic fluid as the cylinder reaches the end of its stroke, allowing for a controlled, gradual deceleration. The cushioning effect is achieved through a combination of fixed pressure, restricted flow areas, and calculated flow control.
Types of Hydraulic Cylinder Cushions
Hydraulic Cushions
- Cast Iron Ring: This is Aggressive Hydraulics’ preferred cushion due to its ability to withstand high loads and maintain performance in demanding applications.
- Spear/Sleeve: These cushions work by restricting hydraulic fluid using a spear or sleeve entering a concentric bore and slowing restricting the area for the fluid to exit the port.
- Progressive Cushioning: This design uses a series of progressively smaller holes allowing more fluid through at the beginning of the cushion and less at the end, providing a smooth, gradual deceleration.
Non-Hydraulic Cushions
- Electrical/Proportional Control: These advanced systems use sensors and electrical control to regulate the movement of the cylinder.
- Bumpers: These are simple soft mechanical stops used in certain low-speed, low-impact applications. (typically, in pneumatic applications only)
Understanding Application Loads, Flows, and Pressures
It is critical to understand the specific loads, flows, and pressures involved in any hydraulic system when designing or selecting a cushion. Improper cushioning can lead to performance issues, including pressure intensification, contamination risks, and even damage from fast start-up or hard stops.
Aggressive Hydraulics has the expertise, calculators, and tools to ensure that the right cushion is selected and properly implemented for each application. Our experienced engineers understand the unique requirements of each project and provide solutions that ensure smooth performance and durability.
Quick Break-Away and Return to Normal Operation
Once a cylinder completes its extend or retract stroke, quick break-away is essential. This means that after the cushioning phase, the cylinder must smoothly return to normal operation without delay. Aggressive Hydraulics designs systems that allow for an easy transition between cushioning and regular performance, ensuring no lag in operations or damage from sudden starts.
Contact Our Experts Today
At Aggressive Hydraulics, we take pride in our Purpose-Built™ Custom Hydraulic Cylinders and our commitment to customer satisfaction. Our customer service team is made up of experts who are ready to assist with any questions or challenges you may face. Whether you need guidance on selecting the right hydraulic cylinder cushion or require support for your next project, our team is here to help.
