Abstract:
Start up marks are one of the major
defects on woven fabric and this defect occurs when
loom restarts after stoppages due to warp tension
variation at the time of start. This defect is more
prominent in high speed looms and it is critical in
manufacturing elastic tapes. In this paper, formation
of start-up in elastic tape on a narrow fabric loom
was analyzed mathematically and provided a
practical technical solution to the problem. In
mathematical analysis both continuous operational
condition and stopping condition of a narrow fabric
loom was taken into consideration and the
developed mathematical model established a
quantitative relationship between excess warp yarn
length fed and the tension variation of warp yarn at
the point of starting the loom. A system simulation
was carried out using the model developed and
compared with the experimental results to show the
accuracy of the model. A tension compensating
device was proposed to avoid formation of the
startup marks. The effectiveness of the proposed
solution was proven practically with a prototype
developed.
