Knitting Machine Production Calculation:
To calculate knitting machine production needs certain information and some calculation. This will be most realistic production value but we cannot get knitting machine capacity in this way. For this we need following figures:
- Machine Speed (RPM)
- Number Of Feeder (F)
- Machine Gauge (MG)
- Machine Dia (MD)
- Count/ Denier Of Yarn Being Used
- Stitch Length (SL)
From these figures we can calculate the length of yarn being used by the machine in one hour and then by converting this length into weight with the help of count given we can calculate the quantity of yarn being consumed by machine in one hour. This would be the optimum production of the machine.
This optimum production can be converted into nominal production by multiplying it with efficiency.
Calculate The Yarn Length Used By The Machine In One Hour:
Number of Needles in Machine = MG x MD x p
Every needle is making one stitch on every feeder because machine is producing single jersey fabric.
Number of stitches produced in one revolution= Number of needles x F
Number of Stitches * SL (mm) * RPM *60
Yarn Consumption (Meter) in one hr= --------------------------------------------------------------
1000 (To convert mm into meters)
Number of Stitches * SL (mm) * RPM *60
Yarn Consumption (in yards) in one hr= ------------------------------------------------------------- x 1.094
1000 (To convert mm into meters)
Calculate The Optimum Production By The Machine In One Hour:
Length of yarn in Yds (Consumed in hr by m/c)
Optimum Prodn for Cotton (Kg) = ----------------------------------------------------------------------- x 0.454
Count x 840
Length of yarn in Mtr (Consumed in hr by m/c) x Denier
Optimum Prodn for Filament (gm) = ------------------------------------------------------------------------------------
9000
From All Above Discussion We Can Understand How To Calculate The Optimum Production Of A Knitting Machine. Now Easily We Can Develop An Equation Which Is Useful In Every Situation To Calculate The Optimum Production Capacity Of A Knitting Machine.
For cotton count:
MG X MD X p X F X RPM X 60 X SL(mm) X 0.497
Opt. Prodn In One Hour (Kg) = -------------------------------------------------------------------
1000 *840 * Yarn Count * 100
For Filament:
MG X MD X p X F X RPM X 60 X SL(mm) X Denier
Opt. Prodn In One Hour (kg) = -------------------------------------------------------------------
9000 x 1000
Nominal Production Per Hour = Optimum Production x M/C Efficiency
Calculate Nominal Production Of A Single Jersey-Knitting Machine Per Hour:
Calculate nominal production of a single jersey-knitting machine per hour from the data given:
Machine Gauge 24
Machine Dia 30 inches
Number of Feeders 90
Machine RPM 26
Yarn Count 24
Stitch length 4 mm
Efficiency 85%
Here,
Number of needles = machine dia * gauge * p (3.14)
= 30* 24*3.14
= 2260 (exact 2260.8 but needles are always in even number so we will take nearest even figure)
Number of stitches produced in one revolution = Number of needles * F
= 2260*90
= 203400
Number of Stitches * SL (mm) * RPM *60
Yarn Consumption (in yards) in one hr= -------------------------------------------------------------------- x 1.094
1000 (To convert mm into meters)
=203400 * 4 * 26 * 60 * 1.094
1000
= 1388015 yards
Length of yarn in Yds (Consumed in hr by m/c)
Optimum Prodn for Cotton (Kg) = -------------------------------------------------------------------------- x 0.454
Count x 840
= 1388015 * 0.454
840 * 24
= 31.23 Kg
At Efficiency 85% The Nominal Production = 26.55 Kilo grams
So, This Machine Can Produce 26.55 Kgs Fabric In One Hour At 85 % Efficiency
Calculate nominal production of a fleece-knitting machine per hour:
In Fleece Fabric we use two different yarns at different feeders and ultimately stitch length is also different. In such case we should calculate separately consumption of different yarn at different feeders. Following example will help in calculating production in case of use of more than one kind yarn.
Calculate nominal production of a fleece-knitting machine per hour from the data given:
|
|
Front Part |
Back Loop |
|
Machine Gauge (MG) |
18 |
|
|
Machine Dia (MD) |
30 inches |
|
|
Machine RPM (RPM) |
28 |
|
|
Number of Feeders (F) |
60 |
30 |
|
Yarn Count |
26 |
16 |
|
Stitch Length (SL) |
4.5 |
2.5 |
|
Machine Efficiency |
85% |
|
Number Of Needles in Machine = MG x MD x p (3.14)
= 18* 30 *3.14
=1696 (exact 1695 but needles are always in even number so we will take nearest even figure)
For Front Part:
Number of stitches produced in one revolution= Number of needles x F
= 1696*60
= 101760
Number of Stitches * SL (mm) * RPM *60
Yarn Consumption (in yards) in one hr= --------------------------------------------------------------------- x 1.094
1000 (To convert mm into meters)
=101760 * 4.5 * 28 * 60 *1.094
1000
= 841312 yards
Length of yarn
Weight of Cotton Yarn = ------------------------------------ x 0.454
Count x 840
= (841312 * 0.454)/ (840 * 30)
= 17.43 Kg
At Efficiency 85% The Nominal Production = 14.85 Kg
This machine will consume 14.85 Kgs of yarn to knit front of the fleece fabric in one hour at 85 % efficiency
For Back (Loop) Part:
Number of stitches produced in one revolution= Number of needles x F
= 1696*30
= 50880
Number of Stitches * SL (mm) * RPM *60
Yarn Consumption (in yards) in one hr= -------------------------------------------------------------------- x 1.094
1000 (To convert mm into meters)
=50880 * 2.5 * 28 * 60 * 1.094
1000
= 233696 yards
Length of yarn
Weight of Cotton Yarn = -------------------------------- x 0.454
Count x 840
= 233696 * 454
840*16
= 7.89 Kg
At Efficiency 85% The Nominal Production = 6.70 Kg
This machine will consume 6.70 Kgs of yarn to knit front of the fleece fabric in one hour at 85 % efficiency
Total Nominal Production For This Machine = (Front Weight + Back Weight)
= 14.85 + 6.70
= 21.55
So, This Machine Will Consume 21.55 Kgs Of Yarn To Knit Front Of The Fleece Fabric In One Hour At 85 % Efficiency
For Filament Yarn: Calculate Nominal Production of A Single Jersey-Knitting Machine Per Hour:
Calculate nominal production of a single jersey-knitting machine per hour from the data given:
Machine Gauge 28
Machine Dia 26 inches
Number of Feeders 120
Machine RPM 30
Yarn Denier 75
Stitch length 4.5 mm
Efficiency 85%
Number of needles = machine dia * gauge * p (3.14)
= 26* 28*3.14
= 2286 (exact 2285.92 but needles are always in even number so we will take nearest even figure)
Number of stitches produced in one revolution = Number of needles * number of feeders
= 2286*120
= 274320
Yarn Consumption (in yards) in one hour = Number of stitches * SL (mm) * RPM *60
1000(to convert mm into meters)
= 274320 * 4.5 * 30 * 60
1000
= 2221992 Meter
Weight of Filament (Kg) = Length In Meters * Denier
9000 * 1000
= 2221992*75
9000 *1000
=18.516 Kgs
At Efficiency 85% The Nominal Production = 15.74 Kg
So, This machine will consume 15.74 Kgs of yarn to knit front of the fleece fabric in one hour at 85 % efficiency