Abstract:
An apparatus for heating an elongate tubular article, such as a heat shrinkable sleeve applied around a welded pipe joint during pipeline construction. The apparatus is in the form of a frame which can be disposed around the article, the frame having a heater device having both longitudinally disposed heating zones and radially disposed heating sectors, each of which can be independently controlled. Alternatively, or in combination, the apparatus can have an air circulation system. Also, a method for shrinking a heat shrinkable sleeve comprising use of said apparatus.
Abstract:
A method for forming a connection between two tubular sections having a polymeric outer surface jacket, using induction heat to fusion bond a casing of similar, non-crosslinked polymer to the outer surface of the tubular sections. Casing with a configuration capable of such fusion bonding.
Abstract:
A method for installing a heat shrinkable sleeve in a cylindrical configuration on an elongate tubular article using a high velocity gas burning heat gun to heat and shrink the sleeve. The gun has a nozzle through which combustion gases exit and has structure that accelerates air and gas toward the nozzle. The gun may be modified to provide greater efficiency of sleeve installation.
Abstract:
An induction heating apparatus for use in pre-heating pipe joints. The induction heating apparatus comprises a frame for applying around the pipe joint, and an induction heating coil made from Litz cable wires.
Abstract:
The invention is directed to an apparatus for heating an elongate tubular article, comprising a frame member adapted to be disposed around said article, a heater with multiple heating zones and a controller for operating the heating device. The apparatus may be used to apply a heat shrinkable sleeve around a welded pipe joint. The heater may be infrared and also may use thin stamped sheets. If a heat shrinkable sleeve is used, the controller may activate the heating zones from the centre of the weld outward to eliminate pockets of air. The diameter of the interior of the frame may change along the length of the frame.