| abstract |
The assembly can be inserted inside two abutting pipes of equal or unequal diameters and form an airtight dam at the weld area, and still allow an Argon Purge to be fed into the dam. It consists of two inflatable bags 11,31 mounted at either end of an elongated flexible tube 10, sealed at one end 22 and so designed to allow both bags 11,31 to be inflated together by pumping air through rods attached by snap-on connectors 16. A small tube 13 passes through the bag 31 that is connected to the rods allowing Argon to be fed into the dam. The device and rods are flexible and will negotiate all bends and reducers. Bags expand independently for unequal diameters, device is inserted and withdrawn deflated. Rubber end caps 12,25,26,27 cover sealing bungs 20,41 carrying the tubes 10,13 and fire protecting spreadable cloth devices 18 overlie the inside ends of the bags 11,31. |