In the workshop, considering welding flanges (Attached) before the bending
operation of a pipe to reduce welding cost, and also for welding efficiency. To do
welding before bending, considerations of the rotation of the flange before welding them
into a pipe.
This is to avoid inaccuracy of flange holes that must match to
another fixed flange after bending. Considering as well, in some other cases, branches,
elbows, and piping tees.
