Screw and barrel package for LSR processing

The Xaloy® LSR Package includes a specially designed screw, barrel, seal, valve, and nozzle, along with other components where needed, such as a feed-pipe adapter. Nordson recommends the package for manufacturers of seals, gaskets, cushioning pads, medical devices, infant feeding items, ruggedized electronic devices, and such kitchenware as baking pans and spatulas.
 
As a specialist in the engineering and manufacture of injection-unit components, Nordson can develop customized packages to meet specific customer requirements, according to Mark Colella, global product manager for the Xaloy brand.
 
“The low-viscosity liquid ingredients for LSR pose a very different set of mixing and metering requirements from those of thermoplastics, and their temperatures must be maintained below the curing point until homogenized material reaches the mold cavity,” said Mr. Colella. “Our LSR Package addresses these unique challenges yet can be retrofitted on a standard injection molding machine in what amounts to a bolt-on conversion.”
 
The components of the Xaloy LSR Package include a single-flight, wear-resistant, 12:1 to 14:1 L/D screw, designed to provide optimum homogenization of catalyst and crosslinking agents without increasing the temperature of the compound. With a feed port moved downstream and two welded cooling jackets, the barrel is designed for a low L/D ratio and provides the intensive cooling required to hold the LSR compound below crosslinking temperature. The Xaloy X-800® barrel inlay is a nickel-based alloy with tungsten carbide, providing the abrasion and corrosion resistance posed by certain LSR compounds. A rear seal is installed on the barrel or as a seal ring on the screw shank, while a Xaloy spring-loaded valve ensures immediate shutoff with low-viscosity LSR compounds. The shutoff nozzle is provided by a partner company that is a longtime supplier to the LSR industry.

   
 Nordson Corporation engineers, manufactures and markets differentiated products and systems used for the precision dispensing of adhesives, coatings, sealants, biomaterials, polymers,  plastics and other materials, fluid management, test and inspection, UV curing and plasma surface treatment, all supported by application expertise and direct global sales and service.  Nordson serves a wide variety of consumer non-durable, durable and technology end markets including packaging, nonwovens, electronics, medical, appliances, energy, transportation, construction, and general product assembly and finishing.   

Nordson Polymer Processing Systems provides customers with engineered components to melt, homogenize, filter, meter, and give shape to plastic and fluid coating materials. Nordson Corporation leverages the collective plastics industry experience from a series of strategic acquisitions to offer a uniquely broad portfolio of industry-leading technologies.  Nordson delivers a full range of precision melt stream products — from screws and barrels for extrusion and injection molding — to filtration systems, pumps, and valves — to the extrusion dies and pelletizing systems to meet the constantly evolving needs of the polymer industry.