Size Data Pc-Program ver 1.0 by Itru Group Ltd
1.1 Introduction
Efficiency analyses in weaving sheds reveal that most significant factors are warp and weft stops. Since mending of warp breaks takes usually more time than weft stops resulting more down time than weft stops. Hence ,the causes , remedies of end breaks must be systematically analyzed and solved.
Our research work carried out in different weaving sheds and at different types of looms and articles reveals that there is a close correlation between end-break rate in weaving and fabric structure . We have developed a Warp breaks projecting PC -program to predetermine the end break rate in weaving so that cost calculations and problems related to fabric structure could be more easily solved . We call this correlation factor end break rate factor . Given fabric construction parameters and the type of loom end break rate Per 100,000 picks could be predetermined . If the actual end break rate is higher than expected it shows that faults in the warp preparation process which should be examined . Mill work should be carried out to reduce the end break rate since the fabric construction is determined by the customer . However, some changes could be carried out in design of articles. Hence , sizing procedure gains a very important role effecting the end break rate . Size Data PC-program developed by ITRU GROUP LTD provides correct and scientific solutions to sizing problems .
Size concentration % is the main key in sizing process and many machine manufacturers and consulting companies use a equation below:
c% = a +b * (d1/p1)
where a, b = constants
d1= Warp yarn diameter in mm
p1= end spacing in mm
However ,end break rate differs from one article to other having same warp count and warp density . Consequently , application of such an equation is useful for the beginning but not really practical.
There are many testing devices available on the market to test the tensile properties (load - elongation ) of warp yarns Tensile properties of warp yarns have significant effect upon the weaving performance which could be summarized as:
-Max
cN/tex
-Min
cN/tex
-Max
elongation %
-Min
elongation %
-Elastic
modules
-%
of elongation in stretch - recovery region
-Work
capacity
-Fatigue
behavior
Size Data PC-program makes use of all these tensile properties of sized and unsized yarns to improve sizing and weaving performance of warp yarns.
The another problem in sizing is the type of raw material and yarn processing . The fibre could be cotton, mmf , viscose polyester ,blend etc and yarn could be carded ,combed or rotor spun and the loom may be air-jet ,rapier or projectile . All these parameters effect the settings on sizing and solved by the PC-program
-g/cc of raw material
-the volumetric density of fibre in yarn cc/g
-tensile properties of yarn
thus many disorders and many parameters are simplified and settled down since the forces affecting end break in weaving mainly determined by tensile properties of warp yarns.
Forces causing end breaks in weaving could be summarized as
a) Maximum warp tension ( at shed opening or beat up)
b) Fatigue of warp yarns (tension curve)
c) Abrasion resistance ( coefficient of friction ,hairiness ,size film properties)
As it can be seen above that tension-stretch curves of warp yarns set the efficiency of weaving performance. Size Data PC-program when used with fabric setting PC- program can be a great help to in solving of very important problems in weaving and sizing .
1.2 The aims of the PC-program
This knowledge based PC-program achieves
-optimum
consumption of sizing agent
-
optimum consumption of heat
-less
warp and weft stops
-scientific
analyses of sizing agents
-optimum
recipe according type of warp material.
Pc-program is also supported by sizing control check lists .By this program
-fabric
structure properties
-technical
data/machine settings in sizing
-sizing
recipe
-quality
values of sized and unsized yarns
-the
problems that warp has to be faced in weaving process could be
determined.
Since all the above parameters are checked sizing process is already under control . However, the main intention of the PC-program is to reduce sizing and weaving costs by reducing end breaks and heat and size consumption . This PC program also succeeds harmonious co-operation between spinning ,sizing and weaving departments and puts an end to passing the buck to others.
1.3 Inputs and outputs
The input list of the program is very detailed list and consists of
a) Fabric structure properties
b) Technical data /machine settings actual
c) tension curves of sized and unsized yarns
d) Actual size recipe
according to given this data program calculates
a) recommended size recipe and computations
b) suggestions for sizing and weaving
c) tension-stretch curves for sized yarns
d) actual and expected (optimum) tension and extension % of sizing machines
e) All technical data and calculation related to sizing machine , sizing process and weaving
This PC-program has been developed through many years of research and experience carried out in sizing sheds and weaving mills. The PC-program is also supported by
b) Warp break projection PC-program
c) warping sizing process control and check lists
Therefore , SIZE DATA PC-program not only sets the sizing process on scientific bases but also ensures better running performance of weaving mills.
Copyright © 1992-2007 by ITRU GROUP LTD.