Shaded twill is formed shade effect on the surface of the fabric. The shade effect is created by the combination some thick to thin twills and thin to thick twills. Stepped twill is formed by steeping a continuous twill and keeping the direction of twill line same or opposite.
Elongated twill is constructed by advancing the points of intersection two or more threads in one direction and one thread in the other direction.On the other hand combined twill is formed by combination two regular twill and arranging them alternately with each others.
The drafting section of the roving frame may be 3 over 3 or 4 over 4 with or without apron roller arrangement. Only the 3-over-3 or 4 over 4 roller with double apron drafting system are still to be found in modern machines offered by manufacturers. In general 3/3 drafting system is used, but for higher draft applications 4/4 drafting system is used.
Yarn number is a measure of the fineness or size of a yarn expressed either as mass per unit length or length per unit. Yarn Count and Yarn Size are synonymous with Yarn Number.There are two systems of expressing yarn number or yarn count.
❶ Direct yarn numbering system (mass/unit length)
❷ Indirect yarn numbering system (length/unit mass)
In a very general way, a fiber is defined as any product capable of being woven or otherwise made into a fabric. It may be thought of as the smallest visible unit of textile production. Fibers may be agricultural products (such as cotton or wool) or units (such as nylon or polyester) manufactured in a chemical plant. Fibers than serve as the raw material in the next stage of textile manufacturing.
Top rollers are held strictly parallel to and in perfect alignment with bottom rollers.//The bottom rollers of speed frame exercise immense inﬂuence on the quality of roving.//The flyer is a special component of the roving frame that helps to insert twist in the roving. The ﬂyer speeds employed normally range from about 1000 to 1400 rpm. The ﬂyers’ special shape offers less air resistance, preventing roving breakages.
A weave in which there are 2 ends and 2 picks in a repeat is called a plain weave. It has the smallest repeat 2 x2. Classification of plain weave: Approximately square cloth, Warp face cloth, Weft face twill, Balanced cloth, Unbalanced cloth.
The process of drawing the warp yarn through the eye of heald frames according to design is called drafting, and the plan which indicates how drafting needs to be done is called drafting plan. It also denotes the number of heald shaft required for a given weave repeat