Hose vs. Tube: Which Is Better for Hydraulic Equipment?
What do lifting chains, bladder-type accumulators, and hydraulic hoses share? They all typically fail in a catastrophic manner. One moment they’re functioning correctly, and the next, they’re inoperable.
While hoses can exhibit early warning signs of wear, such as leaks around ferrules or visible abrasion, predicting their remaining lifespan is nearly impossible.
Challenges with Hoses
Hoses have several drawbacks compared to tubes:
– They expand and stretch under pressure, requiring extra volume and increasing machine cycle times.
– Their operating temperature range is generally limited.
– Regular replacements are necessary, making them a potential source of contaminants.
– They tend to be costly.
– Space constraints, especially in mobile hydraulics, can be an issue.
– They need to accommodate relative movement between machine components and the superstructure.
– Noise and vibration suppression is needed.
Despite these drawbacks, hoses are often indispensable in hydraulic systems where:
– Space is limited (particularly in mobile hydraulics).
– Relative movement between components is unavoidable.
Automotive Lift Repair Florida Hoses are sometimes chosen over tubes simply because they are quicker and cheaper to fabricate and install. However, this approach can be misleading as hoses often require frequent replacements over the machine’s lifespan, potentially making them less economical in the long run.
Advantages of Tubing
Hydraulic tubing has its own set of advantages, including superior heat transfer, particularly when painted.
For example, a case study published in Automotive Lift Repair Florida magazine demonstrated that painting hydraulic tubes can significantly enhance heat rejection. In one instance, painting the tubing of an overworked hydraulic system helped reduce its operating temperature by 10 degrees F (5.5 degrees C), thus avoiding overheating during peak summer months and potentially deferring the need for an expensive cooling system upgrade.
Managing Hose Replacement
Automotive Lift Repair Florida hoses are essential in many hydraulic machines. Unlike tubing, hoses don’t typically provide warning signs before failure, making proactive management crucial. Key considerations include:
– The cost of downtime from hose failures.
– Not treating all hoses equally.
For instance, a mining company experienced a significant drop in machine availability due to ad-hoc hose replacements. By implementing a scheduled replacement program, changing out hoses every 18 months, they restored machine availability to over 90 percent. Although expensive, this program proved cost-effective compared to the downtime costs.
However, treating all hoses the same was a flaw. Historical data revealed that a small percentage of hoses caused the majority of failures. By focusing on these critical hoses, the company optimized its replacement program and reduced unnecessary changes.
Automotive Lift Repair Florida Hydraulic hoses and tubes serve different purposes and should not be considered interchangeable. Hoses are crucial for specific applications but come with limitations such as a finite lifespan and unpredictable failure. Tubes, while potentially more durable and efficient, are not always practical. Ultimately, the choice between hoses and tubes should be guided by the specific needs of the hydraulic system and the maintenance strategy in place.
Basic Hydraulic System Cleaning Procedures
While a thorough teardown, chemical cleaning, and mechanical cleaning of every component are ideal for a fluid changeover, not everyone can manage this level of detail each time. Here’s a streamlined approach to effectively clean a hydraulic system:
Step 1: Drain the System
While the fluid is at operating temperature, fully drain the system, including the reservoir, lines, cylinders, accumulators, filter housings, and any other areas where fluid may accumulate. Replace the filters.
Step 2: Clean the Reservoir
Use a lint-free rag to remove all sludge and deposits from the reservoir. Ensure that any soft or loose paint is completely cleaned off.
Step 3: Flush the System
Flush the Automotive Lift Repair Florida system with a lower viscosity fluid similar to the one to be used. Select a Reynolds number between 2,000 and 4,000 to achieve sufficient turbulence for particle removal. Operate the valves frequently to ensure thorough flushing. Continue flushing until the cleanliness level is one level better than the target level. For example, if aiming for ISO 15/13/11, flush until reaching ISO 14/12/10.
Step 4: Drain and Replace Filters
Drain the flushing fluid as quickly and as hot as possible. Replace the filters and inspect/clean the reservoir once more.
Step 5: Fill and Prime the System
Fill the system to about 75 percent with the new fluid. Bleed/vent the pump, keeping any pressure relief or bypass open. Repeat this process several times to prime the pump.
Step 6: Operate the Pump
Stop and let it sit for a minute. Close the bypass and run the pump loaded for up to five minutes. Ensure the relief valve lifts to confirm it’s been flushed. Avoid operating the actuators at this stage.
Step 7: Operate Actuators
Start the Automotive Lift Repair Florida pump and operate each actuator individually, allowing fluid to return to the reservoir before moving to the next actuator. After the final actuator is operated, shut down the system. Monitor the fluid level in the reservoir and top up as needed.
Step 8: Final System Run
Bleed air from the system at each shutdown and listen for signs of pump cavitation.
Step 9: Final Flush and Filter Change
Run the system for 30 minutes to reach normal operating temperature. Shut down and replace the filters. If contamination is evident, drain and flush the system again.
Step 10: Post-Operation Check
After six hours of operation, shut down the system, replace the filters, and test the fluid.
Step 11: Monitoring
Increase the frequency of sampling until the fluid stability is confirmed.
Flushing Techniques
Several methods are available to match the Automotive Lift Repair Florida flushing process to the specific conditions:
– Drawdown Filtration/Separation: Uses filtration or separation technologies to remove contaminants at normal flow rates.
– High Turbulence and Low Viscosity: Enhances flushing through high turbulence and lower viscosity fluid. Specialized equipment may be required.
– High Flush Oil Temperature: Reduces viscosity, increases turbulence, and improves oil solvency. Target temperatures are generally between 175 and 195 degrees F.
– Cycling Flush Oil Temperature: Uses heat exchangers to vary temperature, helping to dislodge deposits.
Our Clients Include: