How to Make the Best Choice of Hose Reinforcement for Specific Applications

The process of choosing the proper industrial hoses for a fluid system involves many factors, including media pressure, media temperature, the surrounding environment, flow rates, and others. Ensuring that a hose will meet the proper criteria for specific applications requires a sophisticated understanding of different hose components, and how well each will stand up to system conditions. Considerations like reinforcement style, material, and design are essential to choosing the right hose.

By Doug Nordstrom, Senior Product Manager, Hose Product Group, Swagelok Company

Among the most important hose components to consider is the hose reinforcement layer (Figure 1). Without reinforcement, most hoses are only able to handle low pressures, making them unsuitable for industrial fluid system use. Therefore, hoses should contain a reinforcement layer to provide tube strength axially, and longitudinally, to make sure it can withstand the pressures of normal applications. Though there are multiple reasons hoses work effectively for long periods of time, having strong reinforcement layers is the most central – and not all hoses have sufficient reinforcement layers. Working with a collaborative supplier partner will provide the necessary guidance to choose the right hose to do what is expected.

Reinforcement Style

Typically, there are three different types of materials that make up hose reinforcement layers – fiber, stainless steel, or plastic. Wires of these materials are typically constructed into one of two forms of reinforcement; coiled or braided. While it is easier to manufacture coiled reinforcements, they are usually not as durable as their braided counterparts. When pressure is applied to a hose with coiled reinforcements, they are prone to untwisting and potentially damaging the hose core and its cover. Depending on the severity of the damage, it can cause catastrophic failures.

In other words, though coiled reinforcements may appear to make financial sense at the outset, because they are less expensive, hoses constructed with these reinforcements do not last as long, particularly if pressures are high. Highquality suppliers do not typically use coiled reinforcements for this reason. Braided reinforcements are stronger and more resilient (Figure 2). They will not untwist like their coiled counterparts, meaning the chances of damage to the hose core and cover when put under pressure is significantly lower. It may cost more upfront to purchase hoses with braided reinforcements, however, they will last longer and will be able to withstand higher pressures in industrial applications.

It pays dividends to ask suppliers which reinforcement style they use and gravitate toward those using braided reinforcements. Hoses that use braided reinforcements can reduce the amount of time, labor, and money necessary to replace hoses frequently.

After all, industrial fluid systems are harsh operating environments for any hose. Like tires on a vehicle, they need regular maintenance and occasional replacement. No one purchases industrial hoses expecting them to last forever, but the frequency of replacement can be lowered by choosing high-quality hoses in the first place.

Reinforcement Material

Once the type of reinforcement has been selected, it is time to decide which material makes the most sense to reinforce hoses in specific applications. The choice is application specific and will influence the end-use performance of the hose. Choosing the right combination of reinforcements – along with hose core, cover, and end connections – will determine whether a particular hose is right for use in an application. For example, if the application requires outstanding pressure and temperature resistance, it may make the most sense to use a stainless steel braided reinforcement.

If the application requires more flexibility or dynamic performance, then a stainless steel braided reinforcement would not be the right choice. Operators should also consider conductivity when deciding which material is right for hose reinforcement. While sometimes high conductivity is required, it could cause significant safety or performance risks in other situations.

Using a braided metallic reinforcement, for example, will increase a hose’s conductivity, allowing for large electron current flow from one end of the hose to the other. If the two ends of a hose need to be isolated electrically, the hose itself should not be conductive at all. In this instance, it would be necessary to choose a reinforcement material that is not metal, along with a complementary core.

The prices of different braid materials are also considered when choosing the proper reinforcement material. In an application in which either a fiber braid or stainless steel braid will suffice, the fiber braid will likely be less expensive – but, the stainless steel braid may deliver longer-lasting performance by improving a hose’s strength and resisting kinking (Figure 3). A hose supplier who understands specific applications can guide operators about which hose reinforcement will work best at the right price.

Braid Design

Braid designs come in various wire thicknesses and pitch angles, which will affect how flexible and strong a hose may be (Figure 4). The braid will also affect how the hose performs in temperature extremes and other considerations. Most importantly, braids should complement the core material so it can perform at the expected level over time. Using a corrugated metallic core, for example, will provide significant hoop strength to a hose without reinforcement.

In this case, braid reinforcements should be flatter and provide greater resistance to the core expanding lengthwise (rather than diametrically). Depending on the application, different performance characteristics can be determined by the angle at which the braid wires intersect. In other cases, braid wiring characteristics themselves can affect hose performance.

Some suppliers use reinforcement braids with fewer, thicker wires because it is easier to manufacture them. Such construction, however, will limit the flexibility of the hose in question. In contrast, if a reinforcement braid contains many thinner wires, the hose can remain flexible without lessening its strength and pressure resistance.

All Hoses Are Not Created Equal

Operators must pay close attention to hose design when choosing them for their industrial fluid systems because not all hoses are made using the highest standards. As discussed, reinforcement braiding is just one characteristic that can be compromised by lower costs. If operators have a working understanding of reinforcement braids and how they affect overall hose performance, then they will be able to choose hoses that provide the most value over their life cycle. High-quality hose suppliers can advise operators on the best designs for their specific applications to increase reliability and performance (Figure 5).

Finally, it is important to choose a hose supplier who can offer specific training in hose selection to the relevant parties at a facility. If a supplier does not have the capabilities or expertise to advise on hose selection, installation, inspection, and maintenance procedures, it may be time to find another supplier. Industrial hose selection and reinforcement material are crucial to any fluid system’s success, therefore working with partners who can stand behind their products every step of the way is essential.