沉头滤棒关键成型工艺技术研究与应用

Research and application of key forming technology in production of recess filters

为解决沉头滤棒因高克重成型纸定量较大而引发的搭口不牢、易出现爆口问题,同时为提高沉头滤棒圆周、圆度可控性和空腔处硬度,进行了沉头滤棒热熔胶、高克重成型纸的材料特性研究和基棒圆周设计、沉头部分长度设计的成型工艺技术研究。结果表明:①选用使用温度为180℃左右的高熔点热熔胶,沉头滤棒的搭口粘结强度最高,可有效解决沉头滤棒易爆口问题。②随着高克重成型纸定量的增加,沉头滤棒空腔处硬度逐渐增大,滤棒圆度亦逐渐增大,沉头滤棒高克重成型纸定量宜选用100~110g/m2。③针对目标圆周为24.25 mm的沉头滤棒,其基棒圆周控制在23.60~23.70 mm时,沉头滤棒的圆周、压降指标可满足标准设计要求。④沉头部分长度为5 mm的沉头滤棒在空腔处硬度均大于沉头部分为8 mm的硬度,沉头滤棒的复合结构选用R-FF1(5+12+8),即沉头部分长度为5 mm。

In order to prevent broken seams cause by higher grammaged plug wrapper on recess filter and to increase the controllability of circumference and roundness of filter rods and the hardness of the recess section,the characteristics of hotmelt adhesive and high grammaged plug wrapper and the forming technologies for the roundness design and recess section length design of the base filter rods were studied.The results showed that:1)Adopting the hotmelt adhesive with a high melting point at about 180℃,the seam’s bonding strength of the recess filter was the highest,with cracked seams effectively being eliminated.2)With the increase of plug wrapper grammage,the hardness of the recess section and the roundness of the recess filter increased gradually,and the appropriate grammage for the plug wrapper ranged from 100 to 110 g/m2.3)For the filter rod with the target circumference of 24.25 mm,the circumference and pressure drop of the recess filter rod could meet the standard design requirements when the base rod circumference was controlled at 23.60-23.70 mm.4)The hardness of the recess section was higher when its length was 5 mm comparing with 8 mm.The composite structure of the recess filter adopted R-FF1(5+12+8),namely the length of recess section was 5 mm.