MACHINERY | TECHNOLOGY EXTRUSION COATING
Co-extrusion feedblock cuts coat weight by 40%
Machinery manufacturer SAM North America has used an EDI feedblock from Nordson to boost speed – and reduce coat weight – on an extrusion coating line. The combination of technologies has made it possible to cut coat weight by 40% while increasing throughput, thanks to ‘edge encapsulation’. Conventional co-extru- sion yields two or more materials in horizontal layers. However, encapsu- lating inserts developed by Nordson for its co-extrusion feedblock make it possible
BLOWN FILM Multiple layers save on material
GAP of Italy has installed a 27-layer blown film line at its research and development centre in Trecate. The 27-layer bubble film line uses microlayer technology to create structures with improved mechanical characteristics and reduced thickness – which helps to save material. The line is made up of nine
extruders and a 27-layer coextru- sion die that has a diameter of 400mm. The width of the machine is 1600mm. The line also has an automatic air-cooling ring control and software control systems. It can use multiple combinations of materials to create different coextruded film structures. GAP has tested several struc-
tures on the new line, both with blocks and alternating layers.
www.filmandsheet.com
Thanks to the laminar flow structure, it has managed to raise mechanical performance and reduce thickness by up to 25%. Microlayers allow thin layers of polymer to be oriented more easily. For instance, layers of PP can be inserted between layers of PE to increase rigidity and decrease pin holes. GAP has inserted EVOH layers to improve the barrier effect and recyclability.
GAP will also install a series of
three-layer bag production lines – incorporating 100mm die and IBC – at its R&D centre. The lines have been designed for low-range and high-flow production. Some machines include in-line printing and welding to increase production yield. �
www.gapitaly.com
July/August 2021 | FILM & SHEET EXTRUSION 45
to extrude extra material along either edge of this horizontal structure. Using this, SAM found that encap- sulating a PLA co-extrusion with edges of LDPE made it possible to offset PLA deficiencies – particularly its low melt strength – that have limited its melt curtain stability, draw-down ratio, line speed and coat weight. “Using LDPE edge encap-
sulation on our pilot line, we have achieved line speeds in excess of 1200 ft/min 366 m/min) with PLA, against less than 600 ft/min (183 m/ min) with PLA alone,” said Ed Lincoln, vice president of
extrusion sales at SAM North America. The high melt strength of LDPE has made it the most widely used polymer in extrusion coating. “For processors wishing
to replace some portion of their LDPE with biopoly- mers, an obstacle has been that their lower melt strength causes extreme neck-in and edge instability at desirable line speeds,” said Sam Iuliano, chief technologist for Nordson’s EDI extrusion die and feedblock business. �
www.sam-na.com �
www.nordson.com
EXTRUSION
Agent for Australia
and NZ US-based Processing Technologies International (PTI) has appointed Plastics Machinery Works as the representative for its extrusion systems and aftermarket sales and support in Australia and New Zealand.
Plastic Machinery
Works now represents PTI for its complete line of products, including the Super-G HighSpeed and HVTSE DryerLess extrud- ers. In addition, it will act as the region’s dedicated supplier of PTI spare parts. �
www.ptiextruders.com �
www.pmwl.com.au
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
