How to choose the suitable hose?

Usually, we are looking for the hose suitable for certain application, what means the resistance against conveyed fluid and some generic features. Then, we check the pressure/vacuum ranges and temperatures. Having roughly selected the hose type, we are looking for the hose diameter and checking if the minimum bending radius in chosen diameter is sufficient.
We need to remember, that the hose has to be assembled – on the existing end fittings, or provided with couplings. In the case if we are going to use the existing fittings we need to check if our hose is suitable for them – e.g. having the right wall thickness. In some applications, even popular as cooling of heating line, the other factors can be important – cyclic movement or high periodical fluctuation of pressure. In the other ones, the hose has to be strong enough to resist high axial or over bending forces without destruction.
When the hose line is long, the pressure drop factor may become important – it is dependent not only on the diameter, but also on the hose type. In such complex cases we advice contact our specialists – they will help you to find an optimal solution.

CAUTION!

Please do not underestimate the critical parameters as pressure and temperature. If in the process there exists several parameters, always choose the extreme ones. Highest possible pressure and vacuum. Highest and lowest temperature. If the applied pressure, temperature, kind of fluid can be dangerous for life or health of people we strongly recommend contacting our sales specialists to assure about the selection.
Please remember, that you are responsible for correctness and accuracy of the given data.

Find Your hose using the Hose Review section. It will help a bit, hopefully…

Composite Hoses

The composite hoses consist of many layers of foil and textile wrapped around and kept between two spiral metal wires – internal and external. These hoses are not suitable for self-assembly, so they are supplied as a readymade assemblies only. Their great advantage is very good flexibility – also in big diameters and in low working temperatures, so they are willingly used on road tankers. Carefully chosen material combinations allow to manufacture hoses for extremely low temperatures (cryogenics – liquefied gases), provided with the special thermoinsulation, for very hot, liquid bitumines or flame resistant ones.

Very important feature of composite hoses is possibility to manufacture big diameters (up to DN 300 mm) and long pieces (up to 25m). Thanks to that, they are a good solution for mass transport, e.g. ship-to-shore.

Composite hoses are manufactured according to European Standards EN 13766:2010 and EN13765: 2010, the other national standards in several classes and types. Selected hoses have additional DNV type approvals. Typical maximum working pressures are from 4 to 25 bar.

PTFE Hoses

It is important to distinguish all-teflon hoses and the rubber hoses lined with PTFE. In the classic, all-teflon hose types, the inner layer is made solely from thick PTFE plastic, in form of smooth or convoluted tube, externally reinforced with the steel or plastic braid. In case of rubber hoses PTFE lined, the liner is thin – the hose body is traditionally made rubber hose. PTFE plastic is supplied in two versions: natural – usually translucent, which has good insulating properties and black – antistatic, of electrical resistance less than 10⁶Ω.

Because PTFE is a material of excellent chemical resistance, very wide range of working temperatures, physiologically safe and resistant to ageing, the teflon hoses have virtually wide range of potential applications: from pharmaceutical, cosmetics and food industry through chemical industry up to aerospace industry. Unfortunately, it is quite expensive and difficult to process, so the teflon hoses are not cheap.

The classic teflon hoses, having a thick PTFE plastic layer have additionally a great advantage which makes them irreplaceable in some applications: possibility of integral lining of fittings. The internal layer of PTFE from the hose can be assembled through the inside bore of the fitting and thermally formed on the outside sealing face of the coupling. Thanks to that, fluid passing through the fitting has no contact with the metal of coupling. In such execution, there is also no gap between the plastic liner and the metal fitting hose tail, which can trap fluid residues as in the standard swage.

Thinking about using PTFE hoses it should be noted that:

• High temperature strongly weakens PTFE tube. For the temperatures above 130° C, the given maximum working pressure has to be reduced by 1% for each 1° C above.
• Standard, extruded PTFE is quite permeable for gases. For gas applications the other, special versions of hoses should be used.
• PTFE is rather delicate kind of plastic, easy to damage mechanically, e.g. during cleaning and assembling. Necessary care should be taken.

Assembling fittings requires swaging press, while assembling integrally lined fittings – requires additional tools and thermal processes, so these hoses are not designed for self assembly. We supply them only as a readymade assemblies with couplings.

Integrally Lined Couplings

Teflon hoses with the thick PTFE plastic layer have additionally a great advantage which makes them irreplaceable in some applications: integral lining of fittings. The internal layer of PTFE from the hose is assembled through the inside bore of the fitting and then thermally formed on the outside sealing face of the coupling. Thanks to that, fluid passing through the fitting has no contact with the metal of coupling. In such execution, there is also no gap between the plastic liner and the metal fitting hose tail, which can trap fluid residues as in the standard swage. Cleaning is easy and complete.