Auxiliary Hydraulics in Heavy Equipment

[MikePhua]

In the realm of heavy equipment, the term “auxiliary hydraulics” refers to a secondary hydraulic system that provides power to attachments or tools, allowing them to operate efficiently. This system is crucial in expanding the versatility of machines like skid steer loaders, excavators, and backhoes, enabling them to perform a wide range of tasks. This article delves into the function, design, troubleshooting, and maintenance of auxiliary hydraulics, offering a comprehensive guide for those in the heavy equipment industry.
What Are Auxiliary Hydraulics?
Auxiliary hydraulics are systems built into heavy equipment to power attachments such as augers, hydraulic breakers, and grapples. Essentially, they are an extension of the machine’s main hydraulic system, supplying pressurized fluid to additional components or tools. These systems use hydraulic fluid to transmit force from the equipment’s hydraulic pump to the tool or attachment, which then performs the required function.
Auxiliary hydraulic systems are typically controlled by a joystick or foot pedal and come with various configurations to meet the needs of different attachments. These systems play a vital role in improving the efficiency of construction and demolition projects, as well as facilitating precision tasks that require specific control.
Types of Auxiliary Hydraulic Systems
There are several types of auxiliary hydraulic systems, each designed to meet different operational needs. Some of the most common types include:

• Single-Function Systems: These systems are designed to power a single function on an attachment, such as opening and closing a grapple. They are the simplest form of auxiliary hydraulics and are typically found on older machines.
  
• Dual-Function Systems: Dual-function hydraulic systems are capable of powering two distinct functions on an attachment simultaneously. For example, a bucket on a loader may be able to tilt and open or close at the same time with the use of a dual-function auxiliary system.
  
• High-Flow Hydraulic Systems: These systems are designed for high-flow attachments like mulching heads or large hydraulic hammers, which require significant fluid pressure to operate. They are often used in more demanding applications where extra power is necessary to perform heavy-duty tasks.
  
• Standard Flow Systems: These are typically lower-capacity systems suited for lighter, less power-demanding attachments like smaller grapples, augers, or rakes.
  

The Importance of Auxiliary Hydraulics
The ability to use different attachments significantly enhances the versatility of heavy equipment, allowing it to handle a wider range of jobs without needing multiple machines. For instance, a skid steer loader equipped with auxiliary hydraulics can switch from a snow plow to a brush cutter or concrete breaker with minimal downtime, increasing productivity.
Auxiliary hydraulics also improve operational efficiency and safety. By providing dedicated hydraulic power to attachments, operators can control these attachments with precision, reducing the risk of operator fatigue and improving overall machine performance.
Common Issues with Auxiliary Hydraulic Systems
Despite their importance, auxiliary hydraulic systems are not without their challenges. Here are some of the most common issues that can arise:
Leaks in the Hydraulic Lines
Hydraulic lines are under high pressure, and over time, the seals and hoses can wear out, leading to fluid leaks. This not only reduces the efficiency of the hydraulic system but also presents a potential safety hazard. Regular inspection and maintenance of hoses and fittings can prevent leaks and ensure the longevity of the system.
Insufficient Hydraulic Power
If an attachment is not functioning as expected, such as operating too slowly or not producing enough force, the cause could be insufficient hydraulic power. This can happen if the hydraulic fluid is low, the system is clogged, or the hydraulic pump is malfunctioning. Checking the fluid levels, cleaning filters, and performing a pump diagnostic are all steps that can address this issue.
Faulty Control Valves
The control valve directs the hydraulic fluid to the appropriate part of the machine or attachment. If the valve becomes damaged or blocked, the system may not work properly, or the attachment may not function at all. Regularly cleaning and maintaining the control valve is crucial to avoid such issues.
Incompatible Attachments
Another common issue occurs when an attachment is not compatible with the auxiliary hydraulic system of the machine. Incompatible connections or flow rates can result in poor performance or, in worst-case scenarios, damage to the equipment. It’s important to check that the attachment and auxiliary hydraulic system are compatible in terms of flow rates, pressure, and connection type.
Contamination of Hydraulic Fluid
Hydraulic fluid contamination can lead to a range of performance issues, from overheating to complete system failure. Contaminants like dirt, water, or metal debris can cause internal damage to the hydraulic system. Using the proper filtration system and regularly replacing the hydraulic fluid is essential to maintaining system integrity.
Troubleshooting Auxiliary Hydraulics
When diagnosing issues with auxiliary hydraulics, it is essential to follow a systematic approach. Here are some steps for troubleshooting:

1. Check Fluid Levels: Low hydraulic fluid is one of the most common causes of issues in auxiliary systems. Ensure that the fluid is at the correct level and that it is clean and free from contaminants.
   
2. Inspect Hydraulic Hoses and Fittings: Look for any signs of leaks or damage in the hoses or fittings. Replace worn-out hoses and fittings to maintain proper fluid pressure.
   
3. Examine the Control Valve: A faulty or clogged valve may restrict the flow of hydraulic fluid, leading to performance issues. Clean or replace the control valve if necessary.
   
4. Test the Hydraulic Pump: If the system isn’t generating enough pressure, it might be a problem with the hydraulic pump. Perform a diagnostic check on the pump to ensure it is functioning properly.
   
5. Check Attachment Compatibility: Verify that the attachment is properly connected to the auxiliary hydraulic system and that it is within the specifications required by the machine.
   

Maintenance of Auxiliary Hydraulic Systems
Regular maintenance is key to extending the life of the auxiliary hydraulic system and ensuring that attachments continue to function effectively. Here are a few maintenance tips:

• Clean Hydraulic Fluid: Replace hydraulic fluid regularly and ensure it is free from contaminants. Use the manufacturer’s recommended fluid to maintain proper system performance.
  
• Inspect and Replace Seals: Hydraulic seals can wear down over time. Regularly inspect seals for signs of damage or leaks and replace them as needed.
  
• Clean and Inspect Filters: Hydraulic filters can become clogged, restricting fluid flow. Make it a habit to clean and replace filters to keep the system running efficiently.
  
• Lubricate Moving Parts: Proper lubrication of the hydraulic couplings and connections is essential to prevent wear and tear on the system.
  

Conclusion
Auxiliary hydraulics are a critical component of modern heavy equipment, allowing operators to perform a variety of tasks with ease. From controlling attachments to improving the overall efficiency of a machine, these systems are an integral part of many industries, including construction, demolition, and landscaping.
By understanding the types of auxiliary hydraulic systems, recognizing common issues, and following proper maintenance procedures, operators and fleet managers can ensure that their equipment remains reliable and efficient for years to come.