# Textile Calculation

Problems and solutions of textile

## Necessary Formula for Carding Operation in Ring Spinning

Necessary Formula for Carding Operation in Ring Spinning
Abdullah Nur Uddin Rony
Textile Engineering College, Noakhali

What is Carding?
Carding is a mechanical process that separate locks and unorganized clumps of fiber and then aligns the individual fibers so that they are more or less parallel with each other. It is the core of spinning process that dictates the quality of yarn and the end product. Carding is the most important process in spinning. It is called heart of spinning process.
Important Formula for Carding:

Draft constant     Delivered length
1. Draft = …………...….. = ………………..
D.C.P.            Feed length

Wt of material feed/yd
2. Total draft = …………………......……….
Wt of material delivered/yd

Hank delivered
3. Actul draft = ……………………
Hank feed

Present hank
4. Required D.C.P. = Present D.C.P. x …………………
Required hank

Required wt/yd
5. Required D.C.P. = Present D.C.P. x …………………
Present wt/yd

Present draft
6. Required D.C.P. = Present D.C.P. x …………………
Required draft

Total draft x 100
7. Actual draft = ……………….
100 - waste%

Present D.C.P.
8. Required draft = Present draft x ………….....…
Required D.C.P.

60            1
9. Production / hr = Doffer r.p.m. x Doffer dia x p x … x …......….. x Efficiency x Waste%
36    840 x Sliver hank

Surface speed of delivery roller (faster)
10. Technical draft = ………………......…….........……………..
Surface speed of feed roller (slower)

Linear density (Tex) of input materials (lap)
11. Actual draft = ………………….......…......……………………
Linear density (Tex) of output materials (sliver)

Feed wt (grams) / Unit length
= ………………………………………….
Delivery wt. / Unit length

Delivery length (m) / Unit wt.
= …………………………………
Feed length/Unit wt.

12. Total draft = Main draft x Web draft