E-Open Nips with Precision.
A patented hydraulic nip adjustment for calender rolls is said to be the first that combines emergency nip-opening capability (to 3-in, separation) with more precise adjustment of the nip gap than is provided by conventional screw-type mechanical devices. Comerio Ercole SpA in Busto Arsizio, Italy, developed the hydraulic-piston opening system five years ago. It has seven installations, including one on a lab calendering line at DuPont Co., Wilmington, Del. The second U.S. installation, set for later this year, will be a retrofitted tire-rubber calendering line. Comerio's nip adjustment uses Moog servo valves and guarantees accuracy of [+ or -]0.1 mil. It costs about $80,000.