Why Hydraulic Hoses Blow: Common Causes and Prevention

[MikePhua]

Hydraulic hoses are a critical component in various machines, especially in the construction and heavy equipment industries. They are responsible for transporting hydraulic fluid between different parts of the machine to power various functions. However, hydraulic hose failure is not uncommon, and when it happens, it can lead to costly downtime and safety hazards. In this article, we will explore the common causes of hydraulic hose blowouts, their consequences, and how to prevent them.
The Role of Hydraulic Hoses in Equipment
Hydraulic hoses carry high-pressure fluid that powers systems like lifts, bucket movements, or steering in construction machinery such as excavators, backhoes, and loaders. The hydraulic system is essential for efficient operations, and hoses are crucial to its functionality. These hoses must withstand high pressures, temperatures, and harsh environmental conditions to perform reliably. Any failure in these hoses can lead to system malfunctions, creating significant risks for both operators and equipment.
Common Causes of Hydraulic Hose Blowouts
Several factors can contribute to hydraulic hose failure, each stemming from wear and tear, improper maintenance, or external damage. Below are some of the most common causes:

1. Excessive Pressure
   One of the most frequent causes of hose failure is excessive pressure within the hydraulic system. Each hose is rated for a specific pressure threshold. When the pressure exceeds this limit, it can cause the hose to burst or rupture. This might happen if there is a malfunction in the hydraulic system, such as a faulty relief valve, or if an operator unknowingly overpressurizes the system during operation.
   
2. Incorrect Hose Selection
   Using hoses that are not designed for the specific application or the pressure requirements of the equipment is another major cause of failure. For instance, using a hose with insufficient pressure ratings for a high-pressure application can lead to early degradation and eventual failure. It is crucial to select the correct hose material, size, and pressure rating for each machine and function.
   
3. Aging and Wear
   Over time, hydraulic hoses undergo wear and tear, particularly when subjected to constant bending, flexing, and exposure to high temperatures. Exposure to the sun's ultraviolet rays, extreme temperatures, or chemicals can also degrade the hose material, weakening its structure and increasing the risk of rupture. Hose lifespan is typically shortened when not regularly replaced as part of a preventive maintenance schedule.
   
4. Improper Installation
   Incorrect hose installation, such as kinking or over-tightening the fittings, can lead to premature failure. If the hose is bent at sharp angles or twisted during installation, it places undue stress on the material, leading to internal damage. Over-tightening can also stress the hose and fittings, causing leaks or ruptures.
   
5. Friction and Abrasion
   Hydraulic hoses often run through areas where they may rub against sharp edges, metal surfaces, or other hoses. Over time, this friction causes abrasion on the surface of the hose, weakening its outer layer. In some cases, the abrasion can reach the internal structure of the hose, causing it to fail. Using protective covers or routing hoses away from sharp edges can help prevent this issue.
   
6. Contamination and Blockages
   Contaminants such as dirt, debris, or moisture can enter the hydraulic system through damaged hoses or improper maintenance. These contaminants can block the fluid flow, cause system pressure spikes, or chemically degrade the hose material. Additionally, blockages in the hose can increase internal pressure and lead to a rupture.
   
7. Temperature Extremes
   Exposure to excessive heat or cold can affect the performance of hydraulic hoses. Heat can cause the hydraulic fluid to break down and lose its viscosity, which can, in turn, increase system pressure and wear down the hose. On the other hand, extreme cold can make the hose material brittle, making it more susceptible to cracking or bursting under pressure.
   
8. Fitting Failures
   In many cases, hose failures are not due to the hose itself but to the fittings that connect the hose to the equipment. If the fittings are damaged, loose, or corroded, it can cause leaks or hose blowouts. Tightening and inspecting fittings regularly can prevent such issues from occurring.
   

Consequences of Hydraulic Hose Failure
When a hydraulic hose fails, the results can be catastrophic:

• Equipment Downtime: A ruptured hose can cause a system shutdown, leading to delays and costly repairs. In some cases, the equipment might need to be completely disassembled to replace the hose, which adds additional labor costs.
  
• Safety Hazards: Hydraulic fluid is typically under high pressure, and a hose blowout can lead to the dangerous release of fluid, which could harm the operator or nearby personnel. If the fluid is heated or under extreme pressure, it could cause burns or serious injuries.
  
• Environmental Concerns: Hydraulic fluid leaks can lead to environmental contamination, especially when operating in sensitive areas such as near water bodies. The spilled fluid could harm the ecosystem, leading to fines and environmental damage.
  
• Machine Damage: In addition to causing downtime, a failed hydraulic hose can result in further damage to the machine’s components. For instance, if a hose fails while operating a critical component like a bucket or arm, it could lead to mechanical stress or damage to the control system.
  

How to Prevent Hydraulic Hose Failures
Preventing hydraulic hose blowouts is possible with regular maintenance, proper equipment care, and using the correct components. Here are some steps to reduce the risk of hose failures:

1. Routine Inspections
   Regularly inspecting hydraulic hoses for signs of wear, leaks, or damage is the first line of defense. Check for cracks, bulges, abrasions, and signs of oil leakage. Also, check the fittings for tightness and corrosion. Early detection of a problem can prevent catastrophic failure down the line.
   
2. Replace Worn Hoses
   Replacing hoses as part of a preventative maintenance schedule is crucial. Typically, hoses should be replaced every 5,000 to 10,000 operational hours or according to manufacturer recommendations. Pay attention to the manufacturer’s guidelines regarding the lifespan of hoses.
   
3. Use Protective Covers
   To protect hoses from abrasion and exposure to extreme temperatures, use protective coverings such as hose sleeves or jackets. These covers help protect the hose from sharp edges and abrasive surfaces that can damage the hose.
   
4. Ensure Proper Installation
   Ensure hoses are installed without kinks, twists, or excessive bends. Use the correct hose length, and never pull a hose too tight during installation. If routing hoses near sharp edges, make sure there’s sufficient clearance or use protective sheathing.
   
5. Correct Hose Selection
   Always select the right hose for the application, taking into consideration the pressure rating, temperature range, and compatibility with hydraulic fluids. Using hoses with adequate pressure ratings will prevent overpressurization and potential rupture.
   
6. Regular Fluid Testing and Maintenance
   Ensure the hydraulic fluid remains clean and within the correct operating temperature range. Regularly testing and changing the fluid helps prevent contamination and ensures that the system remains in top working condition.
   

Conclusion
Hydraulic hose failures are a common issue in heavy equipment operations, but with proper knowledge, maintenance, and preventative measures, the risks associated with hose blowouts can be minimized. By selecting the correct hoses, ensuring proper installation, inspecting hoses regularly, and maintaining hydraulic systems, operators can prolong the lifespan of hoses and keep their machines running smoothly, reducing downtime and enhancing safety on the job site.