Method and system for welding conduits

Abstract

A system and a method for welding two or more conduits are disclosed. The system includes a root welding tool, a filler welding tool and a support member. The root welding tool root weld a gap to form a root layer configured along end portions, from outer circumferential surfaces side opposite to inner circumferential surfaces side of conduits. The root weld is performed such that spattering of root weld material is prevented. The filler welding tool is utilized to fill the gap. The support member is provided for applying an outward thrust to ensure shrinkage of the filler and root weld materials longitudinally and radially outward, preventing pressing out of the filler and root weld materials along the inner circumferential surfaces side.

What is claimed is: 
     
         1 . A method for welding two or more conduit members, the method comprising:
 aligning two or more end portions of the two or more conduit members in an abutting relationship to define a gap, the conduit members having outer and inner opposite circumferential surfaces sides;   preforming a root weld along the gap from the outer circumferential surfaces side to configure a root layer, in a manner that prevents spattering of the root weld material along the inner circumferential surfaces side;   applying an outward thrust along the inner circumferential surfaces side; and   performing a filler weld along the gap from the outer circumferential surfaces side thereof to fill the gap,   performances of the filler weld upon the application of the outward thrust ensures shrinkage of the filler and root weld materials longitudinally and radially outward, across the two or more conduit members, preventing pressing out of the filler and root weld materials along the inner circumferential surfaces side while performing the filler weld.   
     
     
         2 . The method for welding the two or more conduit members as claimed in  claim 1 , further comprising preparing edges of the two or more end portions of the two or more conduit members for performing the root weld. 
     
     
         3 . The method for welding the two or more conduit members as claimed in  claim 1 , wherein applying the outward thrust further comprises,
 providing a support member along the inner circumferential surfaces side; and   actuating the support member to expand diametrically along the inner circumferential surfaces of the two or more conduits for applying the outward thrust.   
     
     
         4 . The method for welding the two or more conduit members as claimed in  claim 3 , wherein actuating the support member by one of a hydraulically, a pneumatically, a mechanically or a thermally actuating arrangement. 
     
     
         5 . The method for welding the two or more conduit members as claimed in  claim 1 , further comprising releasing the upward thrust upon solidifying of the filler and root weld materials. 
     
     
         6 . The method for welding the two or more conduit members as claimed in  claim 5 , wherein releasing the upward thrust by one of a hydraulically, a pneumatically, a mechanically or a thermally releasing arrangement. 
     
     
         7 . A system for welding two or more conduit members, the system comprising:
 a root welding tool to root weld a gap to form a root layer in the gap configured along two or more end portions of the two or more conduit members aligned in an abutting relationship, from an outer circumferential surfaces side opposite to an inner circumferential surfaces side of the two or more conduit members, the root weld performed in a manner that prevents spattering of the root weld material along the inner circumferential surfaces side;   a filler welding tool to filler weld the gap from the outer circumferential surfaces side to fill the gap; and   a support member provided along the inner circumferential surfaces side for applying an outward thrust therealong to ensure shrinkage of the filler and root weld materials longitudinally and radially outward, across the two or more conduit members, preventing pressing out of the filler and root weld materials along the inner circumferential surfaces while performing the filler weld.   
     
     
         8 . The system for welding the two or more conduit members as claimed in  claim 7 , further comprising an edge preparation tool for preparing edges of the two or more end portions to perform the root weld. 
     
     
         9 . The system for welding the two or more conduit members as claimed in  claim 7 , wherein the support member comprises,
 an actuating arrangement capable of being actuated to expand diametrically along the inner circumferential surfaces of the two or more conduits for applying the outward thrust; and   a releasing arrangement configured in conjunction with the actuating arrangement, the releasing arrangement capable of releasing the upward thrust upon solidifying of the filler and root weld materials.   
     
     
         10 . The system for welding the two or more conduit members as claimed in  claim 9 , wherein the actuating arrangement is one of a hydraulically, a pneumatically, a mechanically or a thermally operated arrangement. 
     
     
         11 . The system for welding the two or more conduit members as claimed in  claim 9 , wherein the releasing arrangement is one of a hydraulically, a pneumatically, a mechanically or a thermally operated arrangement.