Yarn Dyeing Process:
Yarn dyeing is carried out after fiber has been spun into yarn. The process is mainly used to produce various effects of stripes, checks, plaids or other multicolor designs with different colored yarns in the weaving and knitting process. Moreover, threads for sewing and embroidery purposes are all dyed at the yarn stage. In general, yarn dyeing is performed in two methods namely, by batch dyeing method or by continuous dyeing method. In batch dyeing process, the yarn dyeing is performed in three different forms namely cheese dyeing, hank dyeing and beam dyeing. In the continuous dyeing method, the yarn is dyed in the form of rope or individual yarn known as rope dyeing and slasher dyeing method respectively. The general process sequence, irrespective of the type of yarn dyeing method is provided in below.
Flow Chart of Yarn Dyeing:
Winding in cheese frame (low density)
↓
Pre-treatment, scouring & bleaching
↓
Dyeing of yarn package/in slasher
↓
Washing with levelling agent
↓
Drying with hydro extractor
↓
Rewinding of cheese to cone for fabrication
In yarn dyeing process, generally, the time required to complete the process varies based on the machine capacity and dyeing time. The machine capacity depends upon the type of machines employed for dyeing and the time required to complete the dyeing is based on the dyeing method used and the fiber type to be dyed.
Cost Calculations in Yarn Dyeing:
Cost calculations in yarn dyeing are essential for determining the overall expenses involved in transforming raw yarn into finished dyed products. Yarn dyeing is a complex process that includes various stages such as preparation, dyeing, and finishing, each of which requires careful consideration of different cost components. Cost calculations in yarn dyeing involve several factors that contribute to the overall expenses. Those factors are point out in the next segment.
Factors Influencing the Cost Calculations in Yarn Dyeing:
The following factors influence the cost of the yarn dyeing process:
- Preparatory process (cheese, hank or beam)
- Machine production capacity
- Type of dyeing method
- Type of fiber used
- Raw material for pre-processing and dyeing
- Labor cost
- Rewinding and packing method
- Effluent treatment cost
- Electricity bill
- Firewood cost
- Overhead expenses
Example:
A dyeing industry receives an order to dye polyester yarn of 18,000 kg using package dyeing method. In this process, the manufacturer uses two cheese dyeing machines with a total production capacity of 1,400 kg per shift. To operate the preparatory winding process, the factory spends 5 labors with Tk.820/shift. For the dyeing machine operation and packing operation, the factory uses 12 operators to perform all the process including washing, neutralising and packing activity. The average wage of the operator is noted as Tk. 930/shift. Other than this, the raw materials used for dyeing and washing process are provided in Table 4.11. The factory spends Tk.5/kg of yarn processed as electricity bill and Tk.6/kg of yarn as the cost of firewood. The overall effluent treatment expense of Tk.1,25,000 is noted per month and for the boiler operator, administrative staff and supervisor the factory spends Tk.95,000/month. Other common expenses noted are Tk.50,000/month of 30 days. Calculate the cost of yarn dyeing process per kg of yarn processes with 15% profit if the factory works 2 shifts per day.
Table: The raw material cost and consumption details of example
S.No | Chemicals used | Cost in Rs/kg | Actual consumption |
1 | Dye 1 | 740 | 1 % of fabric weight |
2 | Dye 2 | 680 | 3% of fabric weight |
3 | Dye 3 | 910 | 1% of fabric weight |
4 | Fixing agent | 120 | 8 % fabric weight |
5 | Levelling agent | 200 | 5 % fabric weight |
6 | Neutralising agent | 90 | 10% fabric weight |
Solution:
Step 1: Number of shifts required
The total production needs to be done = 18,000 kg
Daily production of the company = 1,400 kg/shift
…………………………………………………Order quantity
Hence, the total shifts required = —————————————
……………………………………………….Daily production
….18,000
= ————
…..1,400
= 12.86 shifts
Company works two shifts per day.
Hence, total days = 6.43 days
Step 2: Labor cost
To complete the order, in winding section 5 operators are used and for dyeing and packing, 12 operators are used with a wage of Tk.820 and Tk. 930 per shift respectively.
Hence, the total labor cost is = (Number of labors × Total working shifts × Wages per shift)
= (5 × 12.86 × 820) + (12 × 12.86 × 930)
= Tk. 52726 + Tk. 1,43,517.6
= Tk. 1,96,243.6
Total Labor cost = Tk. 1,96,243.6
= 1,635.36 USD [1 USD = 120 Taka]
Step 3: Calculation of raw material cost (below Table)
Table: The raw material cost details of example
S.No Chemicals used | Cost in Tk/kg | Actual consumption | Total cost in Tk | |
Dye 1 | 740 | 1 % x 18,000 = 180 kg | 1,33,200 | |
Dye 2 | 680 | 3 % x 18,000 = 540 kg | 3,67,200 | |
Dye 3 | 910 | 1 % x 18,000 = 180 kg | 1,63,800 | |
Fixing agent | 120 | 8 % x 18,000 = 1440 kg | 1,72,800 | |
Levelling agent | 200 | 5 % x 18,000 = 900 kg | 1,80,000 | |
Neutralising agent | 90 | 10 % x 18,000 = 1800 kg | 1,62,000 | |
Total raw material cost | 11,79,000 |
Step 4: Other expenses
Electricity cost = Tk.5/kg of fabric
= 18,000 kg produced × Tk. 5
= Tk. 90,000
Firewood cost = Tk.6/kg of fabric
= 18,000 kg × Tk.6
= Tk.1,08,000
Total cost = Tk.1,98,000
= 1,650 USD [1 USD = 120 Taka]
Step 5: Overhead cost
Effluent treatment expense = Tk.1,25,000/month
Other staff salary = Tk. 95,000/month
Common expenses = Tk.50,000/month
Total overhead cost = Tk. 2,70,000
Company works for this order only 6.43 days
………………………..2,70,000
Overhead/day = ———————
……………………………30
= Tk. 9,000
Therefore, Tk. 9,000 × 6.43
= Tk. 57,870
= 482.25 USD [1 USD = 120 Taka]
Step 6: Total cost of dyeing and packing
Total cost = Labor cost + Material cost + Other cost + Overheads
= Tk. 1,96,243.6 + Tk. 11,79,000 + Tk. 1,98,000 +Tk. 57,870
= Tk. 16,31,113.6
= 13,592.61 USD [1 USD = 120 Taka]
…………………………………..16,31,113.6
Total dyeing cost / Kg = ———————–
…………………………………….18000
= Tk. 90.62
Profit 15% = Tk. 90.62 + {Tk. 90.62 × 0.15}
= Tk. 104.21
= 0.868 USD [1 USD = 120 Taka]
References:
- Handbook of Textile and Apparel Costing by Dr. R. Rathinamoorthy, Dr. R. Surjit and Dr. K. J.Vishnu Vardhini
- Apparel Merchandising by R. Rathinamoorthy and R. Surjit
- A Novel Green Treatment for Textiles: Plasma Treatment as a Sustainable Technology By Chi-wai Kan