When is a lay-flat hose, such as the FLOWINFLAT® PROBUNKER, a better choice than a round hose?

For aggressive chemicals, a hose with a UHMWPE inner lining (also known as UPE) is the most versatile choice. The FLOWINFLEX® MULTIRESCORE is an EPDM suction and discharge hose with a UHMWPE inner lining that handles acids and alkalis as well as hydrocarbons, such as petroleum products. With many other hoses you have to choose between resistance to acids and alkalis or to hydrocarbons; with this lining, that trade-off does not apply.

The inner lining is the deciding factor in material selection, as it is in direct contact with the medium. Also check the concentration and temperature of the product, the working pressure and whether the hose must be suitable for suction. In addition to rubber hoses, SCHIEMA supplies composite hoses with a UHMWPE, UPE or PTFE lining, which are also highly suitable for chemicals. View the full range of chemically resistant hoses.

A food hose must demonstrably comply with standards for materials that come into contact with food; a standard water hose is not subject to these requirements. The main standards are European Regulation (EC) No 1935/2004 and the US FDA regulation 21 CFR 177.2600. The standards a hose complies with are stated on its datasheet.

The difference lies mainly in the inner lining. In a food hose, the lining is free of harmful substances and carbon black, and it does not impart any taste or odour to the product. The reinforcement must not affect the product either: rusting of the helix must be ruled out. Foodstuffs include not only milk and juices, but also edible oils, fats, beer and wine.

With water, the question is also what kind of water is involved. Drinking water has its own standards, while industrial or surface water sets different requirements. An example of a food hose is the LIQFOOD-16-SD: an NBR suction and discharge hose with a white, smooth inner lining that complies with FDA and EU 1935/2004, suitable for milk, vegetable oils, fruit juices, beer, wine and alcohol up to 92%, among others. View all food hoses.

You choose an abrasion-resistant (wear-resistant) hose as soon as you transport abrasive media, such as blasting grit or catalyst granules. A standard industrial hose does not really exist: the choice always depends on the medium. A chemical hose with an EPDM or UHMWPE lining, for example, is not designed for abrasive media.

For abrasive applications, an inner lining of natural rubber (NR), SBR or polyurethane (PU) is suitable. An example from the petrochemical industry is dry catalyst, such as FCC catalyst based on zeolites and aluminium oxide. It is conveyed as hard granules or powder and requires a highly wear-resistant hose.

Also consider the outer cover. Hoses that are dragged across the ground in practice also wear on the outside. The NARCORFLEX® ABRADURA was therefore developed together with an industrial cleaning company and has both a wear-resistant lining and a wear-resistant cover. In addition, the lining stays smooth even in a bend, so abrasive media cannot wear through folds. This significantly extends the service life. View all abrasion and wear-resistant hoses.

For high-pressure steam, use a dedicated steam hose with steel wire reinforcement, such as the FLEXCITED® FLOWINTUBE® VAPORTOR-18-D. This hose is manufactured to EN ISO 6134 Type 2/A and is suitable for saturated steam up to 18 bar working pressure, with a continuous steam temperature of up to 210 °C and a short-term peak temperature of up to 232 °C. The burst pressure is 180 bar. A standard water hose is not designed for this: steam combines high pressure with high temperature, and contact with escaping steam causes severe burns.

The difference between saturated and superheated steam is important here. Saturated steam is water vapour at exactly the boiling temperature corresponding to its pressure; it sits on the boundary between evaporation and condensation. At 1 bar this is approximately 120 °C, at 18 bar approximately 210 °C. Superheated steam has a higher temperature than the saturation temperature at the same pressure and degrades rubber considerably faster. An EPDM steam hose such as the VAPORTOR is therefore designed for saturated steam within the specified operating limits.

Only use suitable high-pressure steam couplings and allow the hose to cool down and drain while depressurised after use. Also view the full range of steam hoses.