Study On The Stretch-Breaking And Spinning Process Of Ramie

In the traditional ramie spinning process, the existence of fiber damage and neps of ramie is caused by opening and carding.And long and double long fiber in the carding ramie sliver has seriously affected the evenness of the yarn. The practice show that stretch-breaking process of ramie can replace opening and carding process to reduce fiber damage and neps of ramie,and also to eliminate long and double long fiber,and can make degummed ramie directly into sliver.However, there are many sticky fibers and fiber clusters in the stretch-breaking sliver.In this paper, the main research contents and conclusions are as follows:Firstly, Process parameters of ramie stretch-drafting was optimized. Concluded that : feeding quantity is between 180 and 210 g/m, pressurized volume is about 1081.48 kg, gauge of stretch-drafting is between 110 and 130 mm, drawing multiple of stretch-drafting area is about 5.0, drawing multiple of prestretch-drafting area is about 3.0.Secondly, some measures to improve the quality of stretch-breaking sliver were discussed: installation of needle roller in the ramie stretch-breaking machine , pre-drafting degummed ramie and gilling stretch-breaking slivers.Concluded that : string rate is reduced by about 18 percent and fiber cluster is reduced by around 25 percent with needle roller; string rate is reduced by about 26 percent and fiber cluster is reduced by around 31 percent by predrafting degummed ramie; string rate is reduced by about 20 percent and fiber cluster is reduced by around 32 percent after gilling stretch-breaking slivers.Thirdly, the effect of different stretch-breaking gauge on the fiber length distribution and short fiber in the stretch-breaking sliver was discussed.Concluded that: after stretch-breaking in different gauge, the average length of fibers is close to stretch-breaking gauge and the irregularity of fiber length is reduced. When stretch-breaking gauge is close to the half of average length of fibers,short fibers are less after stretch-breaking.Lastly, test the quality of pre-drawing,combing,gilling,roving and spinning in the ramie stretch-breaking process.And contract with the traditional ramie spinning's.Concluded that:(1) Compared with ramie carding sliver, in the stretch-breaking sliver, neps of ramie is reduced by about 60 percent, over-length fiber rate is reduced by around 38 percent, short fiber rate is reduced by about 30 percent, irregularity of fiber length is reduced by around 48 percnet.(2) Compared with the traditional ramie spinning, in the ramie stretch-breaking spinning, sticky fiber in the pre-drawing sliver is slightly more, the number of neps of ramie in the pre-drawing sliver is reduced by about 70 percent.(3) Compared with the traditional ramie spinning, in the ramie stretch-breaking spinning, sticky fiber in the combing sliver is slightly more, neps of ramie in the combing sliver is less. Finished product rate of first-combing is increased by about 5 percent, finished product rate of second-combing is increased by around 2 percent, the total finished product rate is increased by about 10 percent. Over-length fiber rate in the combing sliver is reduced by around 50 percent, short fiber rate in the combing sliver is reduced by about 36 percent.(4) Compared with the traditional ramie spinning, in the ramie stretch-breaking spinning, the quality of gilling sliver and roving is slightly better.(5) The quality of ramie stretch-breaking spinning is better than traditional spinning. The stength is increased by about 15 percent, yarn evenness is improved by around 13 percent, the number of nub and snick is reduced by about 57 percent, the number of ramie neps is reduced by around 57 percent, the number of yarn hairiness is reduced by about 10 percent.(6) Critical Twist Factor of the ramie stretch-breaking is about 92 less than the traditional.Parameters optimization of stretch-drafting process ,how to improve the quality of stretch-drafting and quality of semi-finished and finished products of whole stretch-drafting spinning were studied. It showed that ramie stretch-drafting spinning is possible.However, the research of state of raw material and equipment of stretch-drafting is still needed.