CURL CONTROL WITH DRYER AIR CAPS,申请号US1997006419-传众专利搜索

CURL CONTROL WITH DRYER AIR CAPS

申请公布号：WO1997045588(A1)

申请号：US1997006419

申请日期：1997.04.03

申请公布日期：1997.12.04

摘要：<p>The dryer section in a papermaking machine has a single tier of all top felted dryer rolls (24) six to nine feet in diameter. Air caps (42) are employed over the dryer rolls (24) to simultaneously dry both sides of the web (28) to prevent curl and to increase drying rates. The air caps (42) employ blown air at a temperature of 250-900 degrees Fahrenheit and air speeds of 8000-40000 feet per minute. The dryer fabric (32) employed is foraminous with a permability of between 300-1200 cubic feet per minute per square foot and is designed to withstand peak temperatures of up to 900 degrees Fahrenheit and average temperatures of between 500-600 degrees Fahrenheit. A single transfer roll (150), or more advantageously, two grooved vacuum rolls (50) in a vacuum box (54) are disposed between the dryer rolls to maximize the circumferential wrap of the web and, at the same time, support and transport the web between dryer rolls.</p>