| 摘要 |
<p>Trolley using at least one roll to press a strip of foil (a) onto a substrate (b); carries a spot welding appts. using two electrodes (c) for making spot welds at regular intervals between materials (a,b) as the trolley travels along the substrate. The substrate, esp. a pipe (a), is pref. used as a rail along which the trolley travels. The pref. trolley has two profiled rollers mounted on a pair of spring-loaded scissor levers, one lever carrying a spring-loaded plate fitted with electrodes (c). The free ends of the levers are fitted with handles which, when pressed, form two spot welds, and rotate the rollers through a specific angle via a ratchet mechanism, so the trolley moves along pipe (a) by a specified amt. Used in nuclear power plants, molten metal coolant flows along pipes (a) fitted with a Cr-Ni resistant-heating cable to keep the metal liq. when the reactor is switched off. The cable is protected from damage by a stainless steel foil (SSF) (b) spot welded onto pipe (a) by a human using the trolley for fast, accurate welding.</p> |
