International Journal of Textile Science 2014, 3(4): 70-75 DOI: 10.5923/j.textile.20140304.03 Effect of Gauge Variation of Circular Knitting Machine on Physical and Mechanical Properties of Cotton Knitted Fabrics Faisal Abedin 1 , K. M. Maniruzzaman 2 , Ahmad Saquib Sina 3 , Elias Khalil 4,* 1 Department of Textile Engineering, BGMEA University of Fashion and Technology, Dhaka, Bangladesh 2 Department of Knitting Production, Square Fashions Limited, Mymensingh, Bangladesh 3 Department of Wet Processing, National Institute of Textile Engineering and Research (NITER), Dhaka, Bangladesh 4 Department of Textile Engineering, World University of Bangladesh, Dhaka, Bangladesh Abstract This paper deals with the results of an investigation of various gauges of circular knitting machines with a view to producing same single jersey fabric with different parameters. All parameters including machine diameter, stitch length, yarn count, yarn lot, yarn tension etc. but gauges are used for this work is different. Even dyeing has been done at the same time on the same machine by stitching one with other, finishing parameters and processes are also same and done at same time as well to minimize the effects of other variable which can be responsible for changing the physical and mechanical properties like finished width of the fabric, finished GSM (Grams per Square Meter), shrinkage, spirality, bursting strength etc. This is done for finding only the effects which actually affects the fabric properties. Finally the findings or results are as expected with some variations with the results that are thought theoretically. Keywords Circular Knitting, Machine Gauge, GSM, Shrinkage, Spirality, Physical and Mechanical Properties 1. Introduction Knitting is a technique for producing a two-dimensional fabric made from a one-dimensional yarn or thread [1]. It is the method of creating fabric by transforming continuous strands of yarn into series of interloping loops, each row of such loops hanging from the one immediately preceding it [2]. The basic element of a knit fabric structure is the loop intermeshed with the loops adjacent to it on both sides and above and below it. Knitted fabrics are divided into two main groups, weft and warp knitted fabrics [3]. Weft knitted fabrics can be produced in circular or flat knitting machine. The primary knitting elements are needle, cam and sinker. With the variation of the elements different characteristics of fabrics can be produced. The rising demands on knitted garments all over the world motivate the researchers to research about the various knitted fabrics, their production processes, developing new structures. Knitting machine comprise a needle holder that supports a plurality of needles, which are arranged side by side and can be actuated with an alternating motion along their axis with respect to the needle holder in order to form knitting. Single cylinder circular knitting machines are generally provided, at the upper end of * Corresponding author: eliaskhalil52@gmail.com (Elias Khalil) Published online at http://journal.sapub.org/textile Copyright © 2014 Scientific & Academic Publishing. All Rights Reserved the needle cylinder, with an annular element, which is fixed integrally around the upper end of the needle cylinder and is provided with radial cuts, inside each of which a sinker is arranged, and this radial cuts are angularly offset around the needle cylinder axis with respect to the needle sliding channels so that each sinker is located between two contiguous needles [4]. In the circular knitting machine with a great number of knitting needles, when the number of needle increases, the distance between the needles or sinkers have to be shrunk [5]. This investigation is done for scrutinizing the consequences due to change the gauge of the knitting machine. Gauge is a very important factor in terms of circular knitting machine which denotes the density of the needles in cylinder or dial of a circular knitting machine [6]. Typically no. of needles per unit length of cylinder or dial is called gauge. Most of the time, the number of needles per inch is used in terms of gauge [7]. Literally it is thought that the finished width of the fabric with all the same parameters except the gauge will be higher for higher gauge. But what the reason against this phenomenon is described with the practical results. The consequences of various gauges for various fabrics especially for different GSM or fineness of the fabrics can be gained by this research. Machine gauge is the number of needles in an inch which has a great influence in the fabric structure. Not all the yarn counts can be used in same gauge of machine. Usually yarn needs to be fine with the increase of machine gauge. Knitting machines come in various gauges to accommodate the wide range of yarn