The hose is the conveying line of the source extraction installation. The demands placed on the suction hose are:

• wear resistance
• low weight and flexibility
• not affected by extremes of temperatures
• does not give static electric shocks

When long suction hoses have to be used their diameter should progressively increase from the suction casing, with the smallest hose nearest the suction casing not exceeding 2–3 m length. Coupling is carried out with external couplings which are easy to use.