Are reinforced hydraulic hoses safer and more reliable than non-reinforced hoses?

Yes. Reinforced hydraulics hoses offer a higher level of safety and reliability than non-reinforced ones. This is because the reinforcement layer, which can be braided, spiraled, or textile fiber, gives the hose tensile and burst strength, allowing it to withstand high pressures in the system, resist impulse fatigue, and maintain bore shape even when flexed repeatedly. Non-reinforced hydraulic hoses are generally used for low-pressure applications or return lines. Using them anywhere near the system's working pressure can lead to hose failures, fluid injection injuries, or catastrophic pressure losses.

Hydraulic systems can operate at pressures ranging from a few hundreds of PSI for light-duty circuits up to over 6,000 PSI for heavy industrial equipment and mobile equipment. The hose, as one of the only flexible components within this pressure range, has a large impact on whether or not a system will run safely and reliably for many years. Understanding what the reinforcement does mechanically and not just as a term in marketing helps explain why this distinction is so important.

What does "reinforcement" in a hydraulic tube actually mean?

The layers of a hydraulic hose are the inner tube, which contacts the fluid; the reinforcement layer, or several, that bears the mechanical load; and the outer cover, which protects from abrasions, weather, and chemical exposure. The structural core of the hose is the reinforcement layer. This layer can be made from one or more spirals or braids of high-tensile wire. In some low-pressure specialty hoses it is synthetic textile yarns.

Non-reinforced rubber hoses skip this layer completely or use only a nominal layer of fabric intended to retain shape rather than contain pressure. This structural gap is what separates the two types and can be seen in the way each behaves when under load.

Why does reinforcement change the safety equation?

Working pressure margins and burst pressure

Reinforced hoses have a rating for working pressure and burst pressure. This is usually maintained at a ratio of 4:1 between the two. The spiral or wire braid carries the hoop pressure generated by the pressurized fluid. This allows the hoses to function safely below their failure point. The non-reinforced rubber hose was simply not designed to contain hydraulic pressure. By introducing it to pressurized hydraulic circuits, the entire selection process is thrown out the window.

Resistant to fatigue and pressure impulse

Hydraulic systems seldom maintain a constant pressure. Pressure spikes are created by cylinder actuation, pump ripple, valve shifting, and cyclical load, also known as impulse. Reinforced hoses are tested to ensure they can withstand thousands of pressure cycles before the reinforcement layer becomes fatigued or the tube begins to delaminate. The wire structure in non-reinforced equivalents is not strong enough to absorb the cyclic stress. This causes the tube and cover to wear out much faster.

Bore stability when flexing

Hoses bend, twist, and flex as equipment moves. The reinforcement keeps the bore internally round and constant even when moving, protecting flow rate and preventing localized stress. A hose without reinforcement is more likely to kink, flatten, or collapse the bore when it's routed around tight bends. This increases internal fluid velocity and generates heat. It also reduces service life in those areas most likely to fail.

Injection injury risk

Pinhole leaks can cause fluid to be injected through the skin with forces that are far lower than what is considered dangerous. Reinforced hose reduces the chances of pinhole failures because the wire layer stops the tube from breaking under pressure. It is important to note that this is one of the biggest safety differences between the two types of hoses, as fluid injection injuries may cause tissue damage, even if the entry wound appears minor.

When is a non-reinforced rubber hose still appropriate?

Non-reinforced rubber hoses are not obsolete. They have a place in fluid-power systems. However, they cannot be used in lines that carry working pressure or those under pressurized conditions. Uses that are acceptable include:

• Low-pressure drainage lines and case drain routing
• The suction lines are located on the pump's inlet side, where there is a minimal pressure or a slight negative pressure.
• Outside the primary hydraulic circuit, coolant or lubricant lines
• Pilot lines are used in systems designed specifically for low-pressure signals.

It is not about cost or convenience, but rather pressure exposure that makes the difference. The safety margins of a system are maintained by selecting hose types based on application pressure and not only circuit location.

Choose the right reinforced hose according to the application.

All reinforced hoses are not interchangeable. The single-wire-braid construction is suitable for moderate pressure applications. Double-wire braid and multi-spiral constructions, on the other hand, are designed for high-pressure or high-impulse services such as excavator cylinders and boom circuits. The reinforcement layer's effectiveness is determined by matching the hose construction to the system conditions, not just the nominal size.

Hose selection is also influenced by the compatibility of the hydraulic fluid with the expected temperature range and the external environment (abrasions, UV exposures, chemical contact). The cover and tube material must be able to withstand the reinforcement layer and the external environment to ensure the hose delivers its full service life.

The reinforcement of a hydraulic tube is not an extra feature. It is a mechanical requirement for the hose to be able to safely contain pressure. Reinforced hydraulics hoses provide the pressure circuits with the necessary burst resistance, impulse fatigue resistance, and bore stability. Non-reinforced hoses are only suitable for low-pressure applications, such as drain and suction lines. The most important decision in the design and maintenance of hydraulic systems is to choose the right hose for each line.

1. Can non-reinforced rubber hoses be used in any part of a hydraulic system?

The material can be used for low-pressure applications, such as suction lines and case drains, but should not be used on pressurized supply lines or return lines that carry the system's operating pressure.

2. What safety factor is built into the reinforced hydraulic hose rating?

The majority of reinforced hydraulic hoses are manufactured with a ratio of 4:1 between the working pressure and the minimum burst, which gives them a large margin before failure.

3. How long does hose reinforcement last?

The reinforced hose can withstand pressure impulse cycles, flexing, and repeated pressure without becoming fatigued. This extends the service life of the hose far beyond that which would be possible with a non-reinforced one under the same circumstances.

4. What is the difference between spiral-wound and wire-braid reinforcement?

The spiral-wound layers of wire are used for high-pressure and high-impulse applications. Multiple wire layers provide strength to withstand the demands.

5. Why is fluid infusion injury with non-reinforced tubing a concern?

A non-reinforced tube is more susceptible to leaks at high speeds and small diameters, even when the pressure seems moderate.