New Bimetallic Barrel Alloy Boosts Sustainability
Improved durability and wear resistance, a lower coefficient-of-friction, and compatibility with a wide variety of hard-faced flight materials are key features of Dura 686XL™, a new, patent-pending bimetallic barrel-lining alloy for high-speed applications in extrusion, injection and blow mold applications.
Although processing machinery manufacturers and tooling engineers have kept pace with developments in processing plastics at ever higher screw speeds and volumes, little has been done to advance the durability of conventional boron bimetallic barrel linings.
According to Tony Grant, Director of Sales and Marketing at Wexco, screw speeds and throughput rates for filled and unfilled materials have nearly doubled in recent times, introducing an unprecedented degree of wear energy into plasticizing unit assemblies.
“The choice left to molders and machinery builders is to use more expensive barrel linings, those typically used for running highly glass-filled compounds and other severe-wear applications. But, in many cases, I call this approach ‘application overkill.’
“Our new Wexco 686XL alloy provides machine builders and processors with a more affordable, extra-heavy-duty, longer-life alternative, providing sustainable machine performance.”
Calvin Lundeen, Ph,D., P.E. and head of engineering and technical services at Wexco adds, “The unique characteristics of this new patent-pending alloy also include improved damage resistance and a lower coefficient of friction. We’ve found that these features improve wear life without requiring an increase to hardness.”
Dura 686XL has a proprietary alloy chemistry specially formulated for high-speed applications in blow molding and injection molding machines. It’s suitable for use by molders and extruders who want to replace their more conventional linings to improve durability.
Dura 686XL provides excellent resistance to hardness losses caused by elevated temperatures and friction energy. It is compatible with the majority of screw hard-face flight materials and metal constructions.
Its low coefficient of friction improves durability and metal-to-metal compatibility. In standard, recognized tests for determining abrasion resistance—ASTM G75 slurry abrasion tests, and ASTM G65 dry sand abrasion tests—Dura 686XL provided dramatic service-life improvements when compared to nitrided barrels. And it was shown to provide a significant increase in wear life when compared to Wexco’s standard iron-boron alloys and similar inlays.
“In field observations these barrels have out-performed our expectations,” Grant concludes.
Wexco is the industry leader with a reputation for producing the straightest high performance bimetallic plasticating cylinders worldwide. Wexco markets through a network of national & international distributors screw manufacturer’s original equipment manufacturers and machine rebuilders. For more information on their business visit them at www.wexco.com or contact them at 1-800-999-3926.