c purlin or z purlin is a horizontal beam or bar to provide structural support in buildings. Our purlin roll former can produce purlins of different sizes. CZ purlin Roll Forming Machine is also called an Interchangeable purlin roll forming machine or z purlin making machine. In steel construction, the term purlin typically refers to roof framing members that span parallel to the building eave and support the roof decking or sheeting. http://www.reliancerollformer.com/cz-purlin-roll-forming-machine/