EDI Press Release

SUPER-HARD COATING THAT KEEPS DIE LIP EDGES SHARP INCREASES PRODUCTIVITY FOR PROCESSORS OF FILM, SHEET, AND COATINGS

EverSharp™ Technology Promises ‘Much Longer Run Times’ for Indian Manufacturers of Biaxially Oriented Polyester (BOPET) Film

NEW DELHI, February 9, 2006 - A new system for coating flat-die lip surfaces enables extrusion processors and web converters to improve product quality while gaining several whole days of added machine uptime each year, it was announced by Extrusion Dies Industries, LLC (EDI), which is introducing the technology to the Indian market at Plastindia 2006.
Tradenamed EverSharp™, the system is based on tungsten carbide coating, which EDI says lasts eight times longer than the standard chrome plating used for flat die lips. Compared with standard industrial chrome-plating, tungsten carbide is substantially more resistant to micro-fractures during initial sharpening, abrasion during normal use and cleaning, and corrosion, according to Christopher W. Curtin, EDI executive vice president of sales and marketing.
“EDI expects this new coating technology to be of special interest to Indian companies, particularly manufacturers of biaxially oriented polyester [BOPET] film,” Curtin said. “Sharp edges provide the smallest starting points for the propagation of lip buildup that causes die lines and other defects. Because of the high production volumes in the BOPET film industry, taking the die off-line every three months or so to clean and sharpen the lips means thousands of kilograms of lost output. By eliminating the need to take the die off-line, EDI’s EverSharp edges quickly pay back the cost premium over chrome plating by ensuring much longer run times.”

Tungsten Carbide-Coated Lips Are Sharper from the Very Start
The estimate that tungsten carbide lasts eight times longer than chrome plating before being reground to restore sharpness is a conservative extrapolation from the results of standard tests for abrasion resistance carried out on plastics wear surfaces such as screws, knives, and chill rolls, according to Curtin. “Prior experience with tungsten carbide suggests that the lifetime of the lip coating will be measured in years, during which a chrome-plated edge will have undergone numerous re-sharpenings,” he said.
Micro-photographic close-ups of the edge radii of new die lips show that tungsten carbide-coated lip edges are actually sharper from the very start. “Unlike tungsten carbide, chrome plating undergoes micro-fracturing in the very act of being sharpened for the first time,” Curtin said. “In addition, the normal cleaning required to remove lip buildup will scratch chrome plating, while the higher abrasion-resistance of tungsten carbide prevents scratching. In fact, we expect this property to be especially valuable for processors of highly filled compounds, which wear away lip surfaces much more rapidly than un-reinforced materials.”