Purlins are designed to bear the weight of the roof deck and are supported by building walls or metal beams. These are used both in pre-engineered metal structures and post-and-beam constructed structures. Roof loads are transmitted through CZ metal purlins to the principal structural elements of the roof; which purlins to use depends on the amount and type of roof loads. These come majorly in C and Z shapes, which are produced using C or Z shape purlin forming machine using hot dip galvanized steel strip or hot roll steel strip. The strip is de-coiled, leveled, roll formed, punched, measured and cut.