It is worth noting the advanced cousin: . This is the same 45-degree inclined position, but a "restriction ring" (a plate with a hole) is placed over the pipe joint. The welder must weld through a gap of only 1-2 inches between the ring and the pipe. This simulates welding in a congested pipe rack or against a bulkhead. 6GR is currently considered the gold standard for offshore and structural pipe welding.