Indian extrusion systems manufacturer Rajoo is claiming multiple firsts with its recent sale and installation of a blown film system at Turkish processor Sahin Plastik ‐Vakum. The new blown film line is already up-and-running, processing about 240kg/hr of a barrier film.
For Rajoo (Rajkot, India) the sale is seen as a landmark in that it places an extrusion line in a market and application still largely dominated by the major European and North American extruder manufacturers. The line is the first 7-layer system made and sold by Rajoo and, claims the manufacturer, also the first 7-layer system made in Asia.
The 7‐layer CE compliant extrusion system is comprised of two 60-mm grooved feed extruders (for layers A and G), two 50-mm grooved feed extruders (C, E) and three 40-mm smooth bore extruders (B, D, F). It is equipped with a 400-mm die (a stack-type die made by Rajoo, with horizontal melt flow paths) and an internal bubble cooling system. The machine is equipped with gravimetric feeding and blending of seven main components and 11 secondary components.
The blown film extrusion line also incorporates an automatic film thickness control system with segmented disc. The thickness is measured using two solid-state high definition non‐contact capacitive sensors with 0.1-micron resolution; the thickness control system is especially designed for nylon- and EVOH-based barrier films. The sensors are mounted on a rigid O‐frame scanner, which is mounted after the nip rollers. The film is wound on a back‐to‐back dual‐station load cell controlled surface winder with taper tension control, producing rolls of up to 1000mm in diameter.
Sahin is using the line to process a 200-micron barrier film with the nylon barrier layer 50 microns' thick. The lay‐flat width is 1010mm, for an output of 240 kg/hour, and Rajoo says thickness variation is under ± 3% on 2‐sigma and width variation is less than ±3 mm.