Date of Award


Degree Name

Bachelor of Science


Paper Science and Engineering


A secondary headbox has been designed for the WMU pilot plant fourdrinier papermachine to facilitate research into the formation and final sheet properties of two-ply webs. A thorough literature search was undertaken to determine the design criteria of a headbox and the means used to meet those goals. The result was a hydraulic secondary headbox. The stock for the second ply enters the headbox, passes over one baffle and under another, then flows through a closed channel with eight bends in it. The stock then flows through a short straight section, makes a 90° turn, and then flows to the slice. A Coanda element has been added at the exit of the slice to cause the jet to leave the headbox parallel to the wire, in effect, laying the second ply on the first ply. The secondary headbox should be built and operated on the papermachine to determine its ability to make two-ply sheets.