We will have to go to LIGHT POLE TOOLING and PRODUCTION PROCESSING.
First, we shall know that for conic pole and octagonal pole, press brake tooling is different.
Normally Octagonal pole is with 86 degree top tool and 88-degree bottom v block. The tool cross-section is the same for the whole tool length.
While the Conic pole is with the conic top/bottom (male/female) tool. Tooling is with slope, one side small and another side big diameter.
For Pole diameter up to 340mm, we can make one welding seam pole on the machine as normal;
If for pole size 340~500mm, we will have to make 2 welding seam poles;
pole diameter 350-500 x 12m, normally is with a 2-welding seam. the advantages:
1) save material. 0.5mx3.14 = 1.57m, plate width will be wider than 1.6m if we remove the edge. the pole will be one size smaller. when we cut it into a trapezoid, the plate will not be used effectively.
2) balance the seam welding stress.
for Dia.500mm x 12m pole with one welding seam, the welding seam will make the pole curved because of the welding stress. such big size pole will be difficult to straight. if we make two welding seams, two side welding seams will be balanced.
WHILE SOME customers would like to insist one-piece plate big diameter pole. the diameter also can be limited by Tandem hydraulic press brake throat depth. normally we push the pole plate forward or backward to finish bending. If throat depth is not enough, we can turn the pole left/right side. It looks that we solve the problem, but we can find that it will take a long time for the operator to treat it.