SCREWS AND BARRELS | MACHINERY


Getting tough with screws and barrels


Screw and barrel producers are developing alloys and coatings that offer the durability to handle today’s new high-performance compounds. Mark Holmes reports


Plastic compounds that provide ever higher levels of physical performance in demanding applica- tions are placing greater strains on the machinery that produces them. In the compounding arena, screws and barrels are under the greatest pressure to deliver with certain sections of the extruder subject to sustained attack from both corrosion and abrasion. Extruder manufacturers and suppliers of screw and barrel parts are now meeting this challenge through the development of new coatings and substrate materials. Germany’s C A Picard International, a leading manufacturer of wear parts for extruders, recently developed a barrel liner for the most highly demanding processing environments. “New applications demand innovative materials that guarantee a stable process,” says Dr-Ing Katharina


www.compoundingworld.com


Diehl, Development Engineer at the company. “Typically, materials are either resistant to corro- sion or sustain abrasive wear. It has always been a desire of the compounding industry to find a wear-resistant material that can withstand corrosion and abrasion. However, over the past decade requirements have increased as new compounding materials have been developed that have two significant characteristics during processing – they combine both abrasive and corrosive wear,” she says. “In the majority of processes, the need for high-performance wear protection is confined to a specific zone within the process. Consequently, this zone must be replaced at regular intervals that are far too frequent from the producer’s perspective. The process of replacing this wear zone involves machinery shutdowns that can easily last for several


Main image: Producers of extruder barrels such as Reiloy are working to create alloys and coatings that better handle wear and corrosion


August 2021 | COMPOUNDING WORLD 55


IMAGE: REIFENHAÜSER


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  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77