| 摘要 |
<p>Internally anti-corrosive coated pipes are welded after sliding a push fit sleeve over each pipe end. Both pipe ends are machined with a circumferential groove in the bore. The sleeve over one pipe end projects some distance over the pipe end-face and has a circumferential internal groove, machined to form part of a small airchamber, which is formed when the second sleeve provided with a slealing lip at its end is pushed home to fit inside the groove in the first sleeve. The chamfered ends of both sleeves enable a seal weld to be made. Flame impingement to the coating during welding is thus avoided. The outer ends of both sleeves are also sealwelded.</p> |
