Spring Applied Hydraulic Release Parking Brake System

[MikePhua]

Parking brake systems are crucial safety components in heavy equipment, especially when the machine is stationary and at risk of moving or rolling unintentionally. The Spring Applied Hydraulic Release Parking Brake (SAHR) is a common and efficient parking brake design in heavy equipment. Below, we will explore the working principle of this system and offer maintenance tips to ensure it operates effectively.
Working Principle
The Spring Applied Hydraulic Release Parking Brake combines the benefits of both hydraulic and spring mechanisms to provide powerful braking control when the vehicle is parked. The system consists of a hydraulic cylinder, spring, and brake discs. Here’s how it works:

1. Engaging the Brake: When the equipment is parked, hydraulic pressure is released from the system, and the spring automatically applies pressure to the brake discs, effectively holding the equipment in place. The spring ensures that the brake remains engaged even in the event of a hydraulic failure.
   
2. Releasing the Brake: To move the equipment, hydraulic fluid is pumped into the hydraulic cylinder, compressing the spring and releasing the brake discs. This action is typically controlled by a button or switch operated by the operator.
   

Advantages

1. High Reliability: The spring provides continuous braking force, meaning the system is dependable even if the hydraulic system fails, ensuring the equipment remains safely parked.
   
2. Automated Operation: The hydraulic release of the brake is convenient and minimizes manual intervention, increasing the operator’s efficiency.
   
3. Space-Efficient and Simplified Design: Compared to traditional mechanical braking systems, the Spring Applied Hydraulic Release Parking Brake is more compact, saving space and simplifying the overall system design.
   

Maintenance and Care
While the SAHR parking brake system is relatively straightforward, regular maintenance and care are essential to extend its service life and ensure reliability.

1. Regular Hydraulic System Check: Inspect the hydraulic fluid for cleanliness and check the fluid level. Any leaks in the hydraulic system could compromise brake performance and should be addressed promptly.
   
2. Check for Spring and Brake Disc Wear: Springs can lose their elasticity or degrade over time, so it’s important to check them regularly. Brake discs also wear out with use and need to be inspected and replaced when necessary.
   
3. Maintain Hydraulic Pump and Valves: The hydraulic pump and valves play a critical role in the system. Regularly inspect them for leaks and ensure smooth oil flow. Proper sealing is crucial to avoid fluid loss.
   
4. Test Brake Function Regularly: Perform periodic brake function tests to verify that the system is still operating as expected and can engage and disengage the brake properly when needed.
   

Conclusion
The Spring Applied Hydraulic Release Parking Brake system is an essential part of heavy equipment’s safety features, offering simplicity, efficiency, and reliability. Regular maintenance and periodic checks will ensure the system's longevity and maintain the safety of your equipment. Understanding its working principle and following best practices for upkeep can help maximize performance and reduce the risk of malfunction.