| 摘要 |
<p>The externally-coated hollow perforated roller has a wall thickness below 0.125 in. pref. of the order of 0.063 in. The % of hole area is greater than 25% when measured at the smallest cross-section (D) of each hole. - Max. number of holes consistent with leaving sufficient material to provide required strength, giving high spinning efficiency. DEAB- DE3114093 C The roll for a friction spinning installation consists of a perforated roll body, which is hollow and carries a coating on its outside. The proportion of the perforated surface is over 25% of the total surface of the roll. The wall strength of the body is below 3.2 mm and the hole width is 0.5-0.75 mm.</p> |
