| 摘要 |
<p>The invention provides firstly a multi-tube conduit sheathed in synthetic resin foam, the surface of the foam providing the outer surface of the conduit; secondly a method of making the conduit involving the use of two coupling plates, with which the conduit ends are preferably provided, to define the ends of a forming head into which a molten mixture of synthetic resin and foaming agent is extruded to form the sheath, the tubes being secured at one end in holes formed in one plate and extending slidably through holes in the other plate; and thirdly a connecting device which includes one of the plates and further includes fittings which are partly inserted in the tube ends and pushed into enlarged cavities at the front or outside ends of the plate holes.</p> |
