# Textile Calculation

## Different Formulas of Loom Calculation in Weaving

Different Formulas of Loom Calculation in Weaving
Mayedul Islam
Assistant Chemist

Production of Loom:
The production of a loom mainly depends on the speed of the loom. Higher speed does not always mean higher production because if it exceeds certain limit, loom stoppages due to excessive warp breakages occurring. As a result of higher speed may even reduce the production to a considerable extent. Other factors which affect production are picks inserted per inch of the cloth, quality of the warp and weft, type of loom i.e plain, dobby, jacquard, automatic etc. types of organization i.e 2- loom system or 4- loom system, size of weft package, type of weft package.
 Loom Calculation
1. Production (calculated) in yds/hr,

Picks per min × 60
= ……………………….
Picks per inch × 36

Picks per min
= ……………….. × 1.667
Picks per inch

2. Production (actual) in yds/hr,

= Calculated production × efficiency

Picks per min × 60
= ………………………. × efficiency
Picks per inch × 36

Picks per min
= ……………….. × efficiency × 1.667
Picks per inch

Example 01:
Calculate the production per hour of a loom running at a speed of 192 r.p.m. with an efficiency of 75%. The number of picks inserted per inch in the cloth is 80.

Solution:

Calculated Production per hour,

Picks per min × 60
= ……………………….
Picks per inch × 36

192 × 60
= ………………….
80 × 36

= 4 yds

So, calculated Production per hour is 4 yds.

And,

Actual production per hour,

= Calculated production × efficiency

= 4 × 75%

= 3 yds.

So, Actual production per hour is 3 yds.

3. Time required to complete a weaver’s beam,

Length in yds of cloth from the beam
= ………………………………………………… (1)
Production in yds of cloth per hour

[(Length in yds of warp – uptake) – waste of warp in yds) × Picks per inch × 36 ]
= …………………………………………………………............................................…… (2)
Picks per min × 60 × efficiency

Example 02:
Calculate the time required to complete a weaver’s beam having 1000 yds of warp on it. The woven cloth is required to have 50 picks per inch. The up-take of warp in weaving Is 6% and the waste may be taken as 6 yds. The loom is running at 200 r.p.m and the efficiency is 75%.

Solution:

Time required to complete a weaver’s beam,

Length in yds of cloth from the beam
= ………………………………………………… (1)
Production in yds of cloth per hour

Now,

Length in yds of cloth from the beam = (Length in yds of warp – uptake) – waste of warp in yds

= (1000 × 96%) – 6

= (1000 × 9.6) – 6

= 934 yds.

And,

Production in yds of cloth per hour,

Picks per min × 60
= ………………………. × efficiency
Picks per inch × 36

200 × 60 × 75
= …………………
50 × 36

= 5 yds.

So, from (1), we have

Time required to complete a weaver’s beam,
934
= …………
5

= 186.8 hours.

So, Time required to complete a weaver’s beam is 186.8 hours.