Selecting the appropriate hydraulic hose is a critical decision in all hydraulic systems, and its importance varies based on the specific application. This decision often poses a challenge for new engineers and technicians, especially when they need to choose between spiral and braided hydraulic hoses. Both types serve the same fundamental purpose: to transport hydraulic fluid among various hydraulic components such as cylinders, reservoirs, valve bodies, and filters. Nevertheless, the complexity of contemporary hydraulic systems demands a thorough understanding of hydrostatics to make an informed choice about the most fitting hose type for a given application.
What’s Braided Hydraulic Hose?
A wire braided hydraulic hose is constructed using one or two high tensile steel wires that are intricately woven and overlapped around a core made of synthetic rubber or another elastomeric material. The braiding process involves a machine that wraps the wires in a tight crisscross pattern around the hose, providing it with the ability to flex and make sharp bends. This overlapping wire design also greatly enhances the hose’s resistance to bursting. In contrast to spiral wound hoses, braided hoses are better at handling tensile stress, which enables them to maintain tighter bending radii.
Braided hoses are widely favored in hydraulic applications due to their exceptional strength and flexibility. They come in a wide range of pressure ratings and sizes. However, it’s important to note that as the inner diameter (ID) of the tube increases, the pressure rating decreases. This results in the hose having a safety factor of four to one, meaning its working pressure is rated at one-fourth of its burst pressure.
What’s Sprial Hydraulic Hose?
Spiral hydraulic hose is more rigid, commonly used in high pressure applications and where there are no significant space limitations that require the hose to be overly flexible. A spiral wound hose consists of four or six wires depending on the application, helically wrapped and stacked on top of each other, rather than wound like a braided hose. Spiral hose incorporates high-tensile wire which provides the hydraulic hose with exceptional strength, yet it is also very inflexible, with a minimum bend radius. However, a smaller diameter allows for a tighter bend radius.
For example, a small diameter spiral wound hydraulic hose can operate at 3000 PSI with just one layer of spiral, making it inherently flexible. Where a larger diameter hose may require four layers of spiral wire to handle 3000 PSI, which will make it very rigid with a highly reduced bend radius, resulting in less routing flexibility. Spiral hydraulic hose has an extremely high resistance to pressure spikes, which is required for many large diameter, high-pressure applications.
What’s The Difference Between Braided and Sprial?
The decision between spiral wound and braided hydraulic hoses ultimately hinges on the specific requirements of the application, particularly in terms of pressure needs and flexibility. For high-pressure applications that also encounter frequent pressure impulses, a spiral wound hose is generally the superior choice. However, this option comes with a trade-off in flexibility, which can be problematic in confined spaces or in systems requiring frequent, articulated movements, like those found in backhoes or robotic arms. For such scenarios, a braided hose might be more suitable.
As highlighted in Tech Briefs, selecting the right power source in robotic systems is crucial. Often, the choice defaults to electric motors without considering the advantages of hydraulic or pneumatic solutions. Fluid power systems, with their ability to precisely control large forces and offer smoother motion – as well as a degree of ‘forgiveness’ in movement – can be significantly more effective than electromechanical systems in certain applications.
Consider this comparison: a ¼ inch ID 1-wire braided hose, capable of handling 3200 psi, boasts a highly flexible bend radius of just 1 ½ inches. In contrast, the same type of hose with a 1-inch ID, rated for 1300 psi, has a much less flexible bend radius of 5 ½ inches. On the other hand, a spiral hose of ¼ inch ID can handle up to 5100 psi and has a minimum bend radius of 5 inches – a stark difference from the 1 ½ inch radius of its braided counterpart. For a 1-inch ID spiral wound hose, which still handles 5100 psi, the minimum bend radius extends to 12 inches. This is akin to trying to bend a thick steel pipe; there’s a limit to how far it can flex before it risks damage. Yet, it’s evident that spiral hoses can endure considerably higher pressures and pressure spikes compared to braided hoses.
Conclusion
Braided hoses are used in low to medium, less intensive pressure applications such as engines, hydraulic lifts and return lines. Spiral hoses are best for higher pressures and frequent pressure surges such as in hydrostatic drives, large off-road earth moving dump trucks or mining excavators. Simply put, braided hoses are ideal for high pressures requiring tight bend radius, where spiral hoses are best for extremely high pressure, high impulse applications.
How To Choose The Right Hose Fittings For Hydraulic Hoses?
Hydraxio’s 43 series hose fittings and HY series hose fittings are for braided hydraulic hoses, and BW series hose fittings, 71 series hose fittings and 77 series hose fittings are for sprial hydraulic hoses. Hydraxio is a reliable supplier for wholesalers, distributors and brand manufacturers of hydraulic hoses fittings and adapters. View our a wide range of hydraulic fitting and adapters offering.
