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Twin Screws & Cylinders

Since 1973, Xaloy® X-800 bimetallic barrels have proven that they far outlast nitrided barrels in processing rigid PVC, other vinyl materials and plastic-wood composites. Xaloy® X-800 barrels are lined with a composite consisting of superhard tungsten carbide particles uniformly dispersed in a nickel alloy matrix.

  • Last up to 4X as long as traditional Nitralloy barrels

  • More resistance to abrasive fillers

  • More resistance to corrosive volatiles


Screw compatibility

Screw-barrel compatibility is especially critical in counter-rotating twin-screw extrusion because of very high screw-to-barrel loading and the potential for adhesive and abrasive wear at the interface.

Xaloy® 830 screw surfacing is the ideal companion to X-800 barrels. It too is a hard, durable tungsten carbide composite specially formulated for maximum compatibility with X-800 barrels.

We work closely with leading extruder manufacturers and processors on testing various screw coatings to insure compatibility between our barrels and their screws.

Relining or new

Xaloy can serve your needs for longer-lasting X-800 bimetallic twin barrels two ways: by relining your worn barrel or by supplying a completely new barrel.

In relining a worn nitrided barrel, the first step is to bore out the nitrided lining. Using our spin-casting process and proprietary joining methods, we produce a new twin liner with a bimetallic tungsten carbide composite inlay and fit it into the bored out casing. Each job gets a perfect custom fit. This is critical to insure proper heating and cooling of the plastic during processing. Relining is highly cost-effective because the casing usually does not require replacement. Second-time and subsequent relining jobs cost less than first-time relines because there is no need to bore out the worn liner. We simply press out the old unit and replace it with a new X-800 liner.


If you require information, please call +44 28 9127 1372 or email

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