The most easily distinguishable manufacturing method for carbon steel pipe is spiral weld. In this process the weld is created in the exact same manner as that of DSAW, only the weld seam takes on a helical or spiral appearance due to the way the skelp is rolled to form. Just as in the case with the ERW and DSAW process, a continuous ribbon of skelp is leveled and sent through a series of rolls to form. In the case of the spiral weld process a simple three roll bend is typical and thus makes for faster, more efficient, and less costly manufacturing process. The spiral weld process also allows the mill to roll a much wider range of sizes than DSAW or ERW mills. Also, due to its axial symmetry, spiral weld carbon steel pipe has an inherent ability to maintain straightness. Common spiral weld specs include; API5LB and A252.