Do you fully understand flexible metal hoses and their use? The information below can help to resolve any confusions you may find when choosing the appropriate hose. The flexible metal hose will no doubt be an effective and economical solution in the long run.

Why choose a flexible metal hose?

Vibrations from engines make flexible hoses a crucial part of a piping system. These are specially engineered to absorb vibrations, any offset misalignment, and dampen noise that comes with it. All these issues can actually shorten the lifespan of an entire system.

There are a range of options when choosing a flexible hose. You can choose from EPDM (terpolymer of ethylene, propylene and a diene monomer) or a corrugated metal hose. Both work to reduce the internal stress of pipelines, absorb vibrations, and ensure the correct alignment. However, a stainless steel hose has some qualities which make it a cut above the rest. They have a much longer lifespan than EPDM hoses, which usually run for around 10 to 15 years. A stainless steel hose would not usually fail for the whole system’s lifespan.

Stainless steel hoses will also function whilst subject to a very wide range of extreme temperatures. And lastly, the braid on stainless steel hoses allows it to withstand a lot higher pressure than a EPDM hose. 

How much pressure can a flexible metal hose withstand?

When choosing a flexible metal hose, the working pressure, test pressure, and burst pressure may confuse you. What do these things mean?

The maximum working pressure should be calculated on a continuous basis, at 21 degrees celsius. Usually, it accounts for a quarter of nominal burst pressure.

Maximum test pressure is the maximum pressure before the hose begins to deform. This can be determined by calculating the maximum working pressure to 150%.

Nominal burst pressure means that if the pressure is exceeding, the hose will rupture.

When does a flexible hose need a liner?

Hose liners are designed for when the velocity of liquid or gas exceeds the maximum velocity without a liner.

An interlock liner can help decrease the turbulence posed by high speed, and actually reduce the resonant vibration which could occur.

What does the safety factor refer to?

The safety factor is the ratio between the hoses maximum working pressure and the nominal burst pressure. Usually the ratio is 25%. So, the safety factor is 4:1.