| 摘要 |
<p>Two coaxial tubes are joined by lap welding, one tube being moved whereas the other is stationary. The joint area of the two tubes is preheated and the moving tube is then deformed but the pressure of a pulsed magnetic field so it is pressed onto the stationary tube to form a lap weld. The novelty is that the preheating operation is achieved by passing electric current radially between the two tubes and on the entire peripheries of the tubes, so the joint areas is heated by electrical resistance. Pulsed current may be used for preheating, and the lap welds pref. consist of Cu to Cu; steel to steel; Al to Al; Cu ot steel; Al to steel Ti to steel; Cu to Ti.</p> |
