| 摘要 |
A flexible pipe for the transport of media at a temp which differs from that of the environment has an inner pipe, made of thermoplastic material with a high thermal stability, covered by a permeation barrier. This barrier consists of a compressible padded material and a bare or coated metal foil which is surrounded by a tubular sheath. The inner pipe (18) e.g. for water (16) at 95 deg.C is pref. made of crosslinked polyethylene or un-crosslinked polybutane. The padded band (28) is wound with an overlap (30) and is a woven nylon band, coated unilaterally with an elastomer. A metal foil (10) is wrapped around it with an overlap (20) of 5mm for the edges. This area (20) is hermetically sealed or bonded. The sheath (32) is made of the same material as the inner pipe. The closed-cell PU foam (22) is protected by an aluminium foil (26) and a plastic shell (24)e.g. of low density polyethylene of PVC. USE/ADVANTAGE - This barrier is effective even for water molecules, independent of temp and loses nothing by repeated expansion and contraction. The pipe is easy to make with conventional materials and at low cost.
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