IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 __________________________________________________________________________________________ Volume: 02 Issue: 08 | Aug-2013, Available @ http://www.ijret.org 101 RESEARCH REGARDING CALCULATION OF THE TENSILE FORCES OF POLYURETHANE FILM AND PROTECTIVE PAPER, IN THE PROCESS OF POLYURETHANE – PAD – PROTECTIVE PAPER. Gheorghe Vasile 1 , Alexis Negrea 2 1, 2 ”Valahia” University , Romania, gigi.vasile@velfina.com, alexis.negrea@yahoo.com Abstract In this paper it is analyzed in terms of kinematics and mechanical, stress occurring in protective paper all the way. It will be analyzed forces and tensions that arise in paper strip in the stretch area, stretching determining race. It follows determination of a continuous tension in the paper strip to optimize the operation Keywords: paper route, tension, polyurethane --------------------------------------------------------------------***-------------------------------------------------------------------------- 1. POSITIONING AND KINEMATICS OF PROTECTIVE PAPER ROUTE. As it shows figure 1.the protective paper and polyurethane film ahs different routes. The protective paper has the blue color route and polyurethane film red color route. Both are wrapped in rolls, rolls that will be unrolled by operating with gear motors groups. Both routes follow a predetermined route, routes set by positioning of fixed rollers to engine rollers where they unite and final product will be cut. Figure1. Position of rolls for the two routes The route of protective paper (figure 2) is determined by the impose by conditions for achieving the final product that means package of polyurethane – pad – protective paper. This package has different dimensions in terms of length and width of the package. Therefore for packages smaller than the width of the paper this is cut to the direction of transport, the rest of paper is recovered by wrapping on a roll. The cut is made on the engine roll 5(ω2) after the strip is cross over roll 6. Strip stretch is made between rollers 5 and 2 by a roller mounted on a swing arm (calender). Roll 1 leads the band in the motor area of the package, package is taken by the group of pressing rolls, lead into the cutting die and towed by engine rolls (ω1). Figure2. Protective paper route Position of stretch roll Operation from two points of protective paper strip is required by cutting step (cutting) because the package must stop during cutting; during this the strip stays free without tense. For maintain the tension in the strip this is made with gravitational system roll – swing arm. Command of engine roll 5(ω2) is