Company Information - News & Events
January 26, 2010
Foam Capabilities Provide Multiple Options for Efficient Processing
Over the past few years, Davis-Standard has expanded its foam technology to improve efficiencies and capabilities for processors in the food packaging, automotive parts, graphic arts and industrial product markets. These improvements have been especially beneficial in a challenging economy where cutting costs is essential. The many options available include specialty dies, long L/D extruders, single screw tandem foam systems, counter or co-rotating twin screw foam systems, new feedscrew designs, supervisory controls and a range of downstream equipment. Capabilities encompass high output processing of PS, LDPE and PP foam. Hydrocarbon, atmospheric, and dual gas systems are available for high accuracy metering of blowing agents.
These technologies have been highly successful in the field and three of them are outlined below. They include an AB coextrusion die, 94mm 36:1 L/D counter-rotating twin screw foam extruder, and new feedscrew technology.
AB Coextrusion Die
The AB coextrusion die provides multiple orientation benefits, a 4-to-1 blow-up/stretch ratio and requires fewer blowing agents to achieve a high-density product. This die, as with other ABA and ABC foam die technology offered by Davis-Standard, is capable of processing rigid and foam structures simultaneously. Davis-Standard is the only equipment supplier to provide complete systems for rigid on foam extrusion technology. The AB, ABA and ABC coextrusion die designs are used for applications such as barrier packaging, absorbent foam technology and meat tray processing.
94mm 36:1 L/D Counter-rotating Twin Screw Foam Extruder
Davis-Standard’s 94mm 36:1 L/D counter-rotating twin screw foam extruder was
developed specifically for high-output PE foam processing. This extruder allows for melting, mixing and cooling with minimum shear in material. The extruder’s feedscrew is specifically designed to bring the material to the desired temperature with a quick cool-down, essential in foam extrusion for maximum density reduction.
New Feedscrew Design
A recent feedscrew design for the tandem foam extrusion system increased output rates by up to 20 percent. Davis-Standard’s high-output screw demonstrated a higher energy efficiency of as much as 40 pounds (18 kilograms) per horsepower during operation. This screw takes that a step further with a dynamic seal design that prevents gas from leaking in a tandem extrusion arrangement. The screw also minimizes shear while providing efficient cooling and mixing capabilities.
Foam extruders are available in 2 ˝ to 16-inch (64 - 400mm) diameters with L/D ratios of 30:1 and higher. Dies are offered with remote die lip gap and choke adjustment, coextrusion technology, and fully automated die lip gap and choke assembly with PLC control and recipe storage. Downstream options include cooling and sizing mandrels, dual and single “S” wraps, winding systems and processing equipment. In addition, Davis-Standard can provide turnkey product solutions and weight reduction solutions for solid sheet applications.
For more information, contact Steve DeAngelis at sdeangelis@davis-standard.com or Fred Schrafft at fschrafft@davis-standard.com.
Line running absorbent foam for meat packaging.
