Sectional Warping

• Also called Indirect warping.
• It was developed for pattern warping for making fancy designs.
• Striped designs can be made easily over the beam. 
• It is a 2 stage process and warping speed is less than that of direct warping.
• The output is directly the weaver’s beam, ready to mount over the loom.
• The beam is prepared in sections.

 

Process specifications

• Winding speed : Upto 800 mpm 
• Beaming speed : upto 300 mpm
• Working Width : 1800 to 4200 mm
• Package : Weaver’s beam
• Creel type : H-Creel (used for low speed warping)
• Drum circumference : 3140 mm
• Cone angle : 7⁰ /8.5⁰ /10.5⁰

Textile Fractional cover and Cover factor (with its derivation)

Cover factor is a logical estimation of the percentage area of the fabric covered by the yarns and fiber. 

d = diameter

d/2 = radius

Fractional cover = d/p

Assumption :-

1. Diameter of yarn is uniform (i.e circular in cross section.)

2. Maximum cover factor is 28.

3. Yarn are lying in same plane

Fractional cover = Area covered by yarn /total area

d = 1/28√Ne 

p = 1/N

F.C = (1/28√ne ) X (1/N)

F.C = N/28√Ne

WARPING

OBJECTIVE

• Forming a parallel sheet of yarn onto a warpers beam or section beam from single end packages.
• Cones winding for warping is done at higher tension.
• Static eliminator  device is used for yarn producing high static charge.
• Direct warping is done mostly when sizing is required and large number of ends are required in weaver’s beam. 
• Section warping usually done if sizing is not required.

Direct Warping 

• Winding speed : Upto 1200 mpm
• Beam Diameter : 800 to 1600 mm
• Width of machine : 1400 to 2600 mm

Secondary motions

Secondary motions in LOOM from Nitish sharma

                         Weaving Technology

Weaving is the most popular way of fabric manufacturing. It is primarily done by interlacing two orthogonal sets (warp and weft) of yarns in a regular and recurring pattern. Actual weaving process is preceded by yarn preparation processes namely winding, warping, sizing, drawing and denting.

Winding converts the smaller ringframe packages to bigger cheeses and cones while removing objectinable yarn faults. Pirn winding is performed to supply the weft yarns in shuttle looms. Figure 1.2 shows various yarn packages used in textile operations (from left to right: ringframe bobbin or cop, cone, cheese and pirn). Warping is done with the objective to prepare a warper’s beam which contains a large number of parallel ends in a double flanged beam. Sizing is the process of applying a protective coating on the warp yarns so that they can withstand repeated stresses, strains and flexing during the weaving process. Finally the fabric is manufactured on looms which perform several operations at proper sequence so that there is interlacement between warp and weft yarns and continuous fabric production.

FABRIC MANUFACTURE

Introduction to Fabric Manufacturing

Fabric Manufacturing Technologies

Textile fabrics are generally two dimensional flexible materials made by interlacing of yarns or inter-meshing of loops with the exception of nonwovens and braids. Fabric manufacturing is one of the four major stages (fibre production, yarn manufacturing, fabric manufacturing, and textile chemical processing) of textile value chain. Most of the apparel fabrics are manufactured by weaving technology though knitting is catching up fast specially in the sportswear segment. Natural fibres in general and cotton fibre in particular are the most popular raw material for woven fabrics intended for apparel use. Staple fibres are converted into spun yarns by the use of a series of machines in the yarn manufacturing section. Continuous filament yarns are texturised to impart spun yarn like bulk and appearance to them.

Textile fabrics are special materials as they are generally light-weight, flexible (easy to bend, shear and twist), moldable, permeable and strong. There are four major technologies of fabric manufacturing as listed below.

Weaving Knitting Non-woven