# Textile Calculation

Problems and solutions of textile

## How to Maintain Relative Humidity in Yarn Spinning Mill

How to Maintain Relative Humidity in Yarn Spinning Mill
Amit Kumar Das
Founder of "টেক্সটাইল ম্যানিয়া" Blog
Pabna Textile Engineering College, Pabna, Bangladesh
Cell: 01770 456240
Email: amitptec6th@gmail.com

Relative Humidity in Spinning Mill:
Relative humidity is the ratio of the amount of water vapour present in unit volume of air to the amount of water vapour required to saturate a unit volume of air under the same temperature and pressure.This is expressed as a percentage.Humidity is absolute terms is the amount of water vapour present in a given of the air. In yarn spinning mill must has to maintain relative humidity. In case of low relative humidity fly dust produced then production will decrease. If relative humidity become high then production will also decrease. So, maintaining optimum relative humidity is one of the major task for a successful spinner. In this article I will discuss on relative humidity with example.
 Spinning mill
Moisture regain is normally calculate as a percentage of the moisture contained in the material on its oven dry or bone dry weight.

Moisture content is the amount of moisture contained in the material and is expressed as a percentage in its original weight.

A woven dry or bone dry cotton when left in standard conditions of relative humidity and temperature, namely 65% and 68’F respectively (as per UK and USA and continent) is supposed to have a moisture regain of 8 ½ %. India has slightly different standard because of the general weather conditions.

Original weight – Oven dry weight
Moisture regain% = …………………………………… ×100
Original weight

Conditioned weight = Oven dry weight + 8 ½ %

Original weight – Oven dry weight
Moisture content% = ……………………………………… × 100
Original weight

Mathematical Problems and Solutions:

Mathematical Problem no: 01
A sample of 110 grains of cotton is found to have oven dry weight of 100 grains. Calculate the moisture regain,moisture content and conditioned weight of the cotton ?

Solution:

110 - 100
Moisture regain = ………….....……… × 100
100

= 10%

110 - 100
Moisture content = ………….....……… ×100
110

= 8.09%

Conditioned weight = 100 +8 ½ %
= 100+8.5
= 108.5 grains (ANS.)

Mathematical Problem no: 02
A sample cotton yarn piece of 325 yards has a bone dry weight of 40 grains. Find the conditioned count of the yarn i.e.After the yarn conditioned.

Solution:

Conditioned weight = 40 + 8.5%
= 43.4 grains

Conditioned count = (7000 × 325 ) ÷ (840 × 43.3)
= 62.4 nearly (ANS.)