By: D. Gopalakrishnan

Sardar Vallabhbhai Patel Institute of Textile Management, Coimbatore � 641004

dgk_psgtech@yahoo.co.in

The production of various types of industrial fabrics for industrial application is almost as old as the mechanical weaving operation itself, and these end uses are important today. What are new and extremely attractive to the manufacturer are the growth in industrial textiles and its application in the sectors such as agriculture, construction, geotextiles, automotive, protective apparel, electronics etc. This rapid increase in market potential has led these high profile manufacturers to develop specialized fabric for knitting and serving the end purpose efficiently. In this paper focused various knitted fabrics used for manufacturing of industrial textiles have been reviewed.

1. INTRODUTION

Knitting is one of several ways to turn thread or yarn into cloth (compare to weaving, crochet). Unlike woven fabric, knitted fabric consists entirely of horizontal parallel courses of yarn. The courses are joined to each other by interlocking loops in which a short loop of one course of yarn is wrapped over the bight of another course. Knitting can be done either by hand, described below, or by knitting machine. In practice, hand knitting is usually begun (or "cast on") by forming a base series of twisted loops of yarn on a knitting needle. A second knitting needle is then used to reach through each loop (or stitch) in succession in order to snag a bight of yarn and pull a length back through the loop. This forms a new stitch. Work can proceed in the round (circular knitting) or by going back and forth in rows. Knitting can also be done by machines, which use a different mechanical system to produce nearly identical results.

The knitting process consists of interconnecting loops of yarn on powered automated machines. The machines are equipped with rows of small, hooked needles to draw formed yarn loops through previously formed loops. The fabric is designed to take force in two directions (0� and 90�). For this can be used roving of glass, high tenacity polyester, armid or carbon as pillar threads and weft threads. These fabrics are used for reinforced composites.

Considering though orientation of the force taking yarns (0�, 90�) this fabric is comparable to a woven fabric. However, there is the advantage that yarns are directly oriented and lie absolutely straight in the fabric. This means that there is no loss of tenacity as in the woven due to its crimp effect. Furthermore, the yarn-protective inlay system prevents all fiber damage.