Knitting is done by set of connected loops from a series of yarn in warp or weft direction. Knitted fabrics are divided into two main types; they are
- Warp knitting
- Weft knitting
Warp knitting: In a warp knitted structure each loop in the horizontal direction is made from different thread. Sweater is made by this warp knitting techniques.
Weft knitting: In a weft knitted structure a horizontal row of loops can be made using one thread and the thread runs in the horizontal direction. Most of the knitted fabrics are produced by weft knitting.
Difference between warp and weft knitting: Basically warp and weft knitting process are totally different from one to another. Following are the difference of warp and weft knitting.
|The loops are produced to the length of fabric.
||The loops are produced to the width of the fabric.
|It is elastic to the length.
||It is elastic to the width.
|Elasticity of the warp knitted fabrics is less than weft knitting.
||Elasticity of the weft knitted fabrics is higher than warp knitting.
|Its shrinkage properties is less.
||Its shrinkage properties is higher than warp knitted fabrics.
|Here courses are needed for each pattern row.
||Courses are equal to the pattern.
|Yarns are supplied from beam.
||Yarns are supplied from cone.
|At least one yarn is required for each needle.
||Any number of needle.
|Creating fabric by this method is suitable to dry wash.
||Hand wash is suitable for weft knitting.
|Any design is done easily.
||All types of design is complex.
|It is specially suitable for producing coarse fabric.
||It is suitable for producing thin fabric.
Knitting and weaving are the two different processes to produce knitted and weaved fabric. In modern times both types of fabrics have a great demand in the market. The manufacturing process of this both types is different from one to another.
Knitting: The process in which fabrics are produced by set of connected loops from a series of yarn in weft or warp direction is called knitting. Knitted fabrics are produced by knitting technology. Different types of knitted fabrics are produced by the knitting machine.
Weaving: The process in which fabrics are produced by interlacing two sets of threads according to design is called weaving. Weaved fabrics may be in grey, stripped or colored form. Different types of designed fabrics are produced by the weaving technology.
Difference between knitting and weaving: Although knitting and weaving are the fabric manufacturing techniques but they have a lot of difference. Difference between knitting and weaving are given below.
|knitted fabrics are produced by set of connected loops from a series of yarns.
||Woven fabrics are produced by the interlacing two types of threads.
|One set of yarn is used in this method.
||Two sets of yarn is used for this method.
|Do not require sizing.
||Sizing is required before weaving.
|Yarn preparation is not so necessary.
||Yarn preparation is must.
|Production capacity of knitting is more.
||Production capacity of weaving is less than knitting.
|Production cost of knitting is less than weaving cost.
||Production cost of weaving is higher than knitting.
|About 52% fabrics are produced by knitting technology in textile section.
||About 48% fabrics are produced by weaving techniques in textile section.
|Knitting is done by loop formation.
||Weaving is done by shade formation.
|Elastic property of the knit fabrics are higher than woven fabric.
||Elastic property of the woven fabrics are less than knitted fabric.
|Dimensional stability is lower than woven fabric.
||Dimensional stability is higher than knitted fabric.
Sizing is important for weaving but if the process does not done with proper accuracy then every things will be hampered. For this reason a textile engineer should be very careful during sizing operation. Sizing is done for grey or stripped fabric production. In denim; sizing is done after scouring, bleaching and dyeing process.
Requirements of sizing: A sizing process should fulfill the following requirements, which is important for fabric production.
- Sized warp must be sufficiently strong, smooth and elastic.
- The sizing process must ensure the application of the required amount of size on the yarn or the required size regain.
- The tension of warp yarn at sizing must be regular and constant all the time of warp unwinding from warp beam.
- Yarn strength and loss in elongation should be admitted limits.
- The package, i.e. the weavers beam produced must have cylindrical shape, necessary winding density and yarn strength.
- The sizing process must be efficient, economical and must ensure the production of high quality sized warp.
Choice of size ingredients: Different size ingredients have different characteristics which I have given in one of my blog. Choice of size ingredients are given below:
- The recipe should give the fewest breakage during weaving.
- It should give least amount of exfoliation.
- It should permit easy size removal in later operation.
- It should give good fabric characteristics.
- The recipe should be compatible with the machinery.
- The recipe should not cause any health hazard.
- The recipe should not cause any degradation of textile materials.
- It should be cheap but not necessarily.
- PH should lie between 7 to 7.4.
So, that’s all about requirements of sizing and choice of size ingredients.