| 摘要 |
<p>Two thermoplastic pipes (5,6) are joined by a thermoplastic sleeve (1) with embedded electric heating elements (2,3) which have connections for an electrical power supply. The heat developed causes the zones (11) to fuse and when the power supply is cut off, the solidification causes the sleeve to shrink. The formation of cavities in the centre of the fused zone is prevented by grooves (14) on the outer periphery.</p> |
