| 摘要 |
TECHNICAL PROBLEM: To provide a pipe material for heat medium circulation capable of updating only a tube for heat medium circulation.SOLUTION: By aligning CD pipes 7, 7a and performing extrusion molding simultaneously, sheath pipes of heat medium outgoing and return tubes 9, 9a are formed, and an elliptical heat insulation material layer 11 is formed outside the CD pipes 7, 7a. The heat medium outgoing and return tubes 9, 9a are inserted into the CD pipes 7, 7a in a withdrawable manner, and when an existing pipeline needs update, only the tubes 9, 9a are extracted and replaced with new ones.SELECTED DRAWING: Figure 2 |
