Posts

Textile constants and calculations - important

FIBRE FINENESS, YARN COUNTS AND CONVERSIONS: Micronaire value(cotton)  : The unit is micrograms per inch.  The average weight of one inch length of fibre, expressed in micrograms(0.000001 gram). Denier(man-made fibres): Weight in grams per 9000 meters of fibre. Micron:(wool): Fineness is expressed as fibre diameter in microns(0.001mm) Conversions: ·          Denier = 0.354 x Micronaire value ·          Micronaire value = 2.824 x Denier   YARN COUNTS: It is broadly classified into 1. DIRECT and 2.INDIRECT system. DIRECT SYSTEM: ·          English count (Ne) ·          French count(Nf) ·          Metric count(Nm) ·          Worsted count ·            Metric system :  Metric count(Nm) indicates the number of 1 kilometer(1000 meter) lengths per Kg. Nm =  length in Km / weight in kg  (or) Nm = length meter / weight in grams INDIRECT SYSTEM: ·          Tex count ·          Denier CONVERSION TABLE FOR YARN COUNTS: tex Ne
Post a Comment
Read more

Autoleveller Draw frame basics for spinning Technicians

Image
DRAW FRAME AUTOLEVELLER  Autoleveller is an additional device which is meant for correcting the linear density variations in the delivered sliver by changing either the main draft or break draft of the drafting system, according to the feed variation. There are two types of Autolevelling systems. They are ⦁ Open loop system  Open loop system ⦁ closed loop system  Closed loop system drawframe working principle Most of the drawframe autolevellers are open loop auto levellers.  In open loop autolevellers , sensing is done at the feeding end and the correction is done  by changing either a break draft or main draft of the drafting system. In closed loop system, sensing is at the delivery side and correction is done by changing either a break draft or main draft of the drafting system. Most of the earlier card autolevellers are closed loop autolevellers. But the latest cards have sensing at the feed rollers and as well as at the delivery calender rollers. We can say , b
Post a Comment
Read more

Draw Frame Basics for spinning Technicians

Draw frame Functions Draw Frame  Basics for spinning Technicians Drawing is the operation by which slivers are blended, doubled and leveled. In short staple spinning the term is only applied to the process at a draw frame. In drawing slivers are elongated when passing through a group of pair rollers, each pair is moving faster than previous one. This permits combing, drawing and elongating of several slivers to make them strong and uniform.In most modern worsted drawing sets there are 3 passages of pin drafting and roving process. Objects of drawing: To straighten the crimped, curled and hooked fibers. To make the fiber parallel to their neighbors. To improve uniformity of fibers by drafting and doubling. To reduce weight per length unit of sliver. To remove dust from slivers. To blend raw material of same hank perfectly. TASKS OF DRAWFRAME 1. Through doubling the slivers are made even 2. doubling results in homogenization(blending) 3. through draft fibres get paral
Post a Comment
Read more

Carding Technology Basics for Spinning Technicians

Carding Technology Basics  INTRODUCTION "Card is the heart of the spinning mill" and "Well carded is half spun" are two proverbs of the experts. These proverbs inform the immense significance of carding in the spinning process. High production in carding to economize the process leads to reduction in yarn quality. Higher the production, the more sensitive becomes the carding operation and the greater danger of a negative influence on quality. The technological changes that has taken place in the process of carding is remarkable. Latest machines achieve the production rate of 60 - 100 kgs / hr, which used to be 5 - 10 kgs / hr, upto 1970. THE PURPOSE OF CARDING: 1.       to open the flocks into individual fibres 2.       cleaning or elimination of impurities 3.       reduction of neps 4.       elimination of dust 5.       elimination of short fibres 6.       fibre blending 7.       fibre orientation or alignment 8.       sliver formation TECHN
Post a Comment
Read more