Yarn Diameter Measurement/Yarn Diameter Formula
Pierce developed a formula to calculate the yarn diameter. From an experimental work, he concluded that the specific volume of cotton yarn under moderate pressure is 1.1 cm3/gm.
The density of cotton fibre is 1.52 gm/cm3
A specific volume of 1.1 corresponds to a yarn composed of or approximately 60% of fibre and remaining 40% being air space.
Let yarn count = N tex.
Assuming specific volume = 1.1 cm3/gm
1.1cm3 of yarn has 1 gm weight.
1 gm of N tex has a length of 1/N km or 105/ N cm.
1.1cm3 of yarn has a length of 105/ N cm.
d= yarn diameter in cm.
Converting cm into inches and tex to Ne