Normally, garment factories prepare line loading plan in advance. The line loading planning is done based on the projected daily production capacity of a line. In this post, we will see the method of calculating the number of days needed for completing an order of 35000 pieces. I have also explained the formula for calculating the production capacity of a line.
The problem and the line performance details are given below. (The Problem is taken from a Facebook post)
In the above chart, you can see till Day7, the total projected production volume is 31736.42 pieces. To reach 35,000 pieces you need to produce 3273.63 pieces on 8th day of production. PRoduction needed from each line is 818.41 pieces. So, I did reverse calculation to find how many hours required to make 818.41 pieces per line. It is for 6.0878 hours.
The problem and the line performance details are given below. (The Problem is taken from a Facebook post)
Order Quantity: 35000 pieces
Daily Shift: 10 Hours
Garment SMV: 26.5
Manpower: 125 per line
Number of lines: 4
Line Eff: 50% and Learning curve: Day1:15%, Day2: 35% and Day3:45% Day4 onwards:50%
Absenteeism: 5% (Attendance: 95%)

First, let me explain the capacity calculation formula with absenteeism:
= (Daily Available minutes / Product SMV)
= (Daily Shift hours x 60 x Manpower x Line Eff% x Employee attendance %)/ Product SMV
In the first day of loading projected production capacity (when line Efficiency =15%)
= (10 x 60 x 125 x 15% x 95%)/26.50
= 403.30 pieces
In Day2 production capacity (line efficiency 35%)
= (10 x 60 x 125 x 35% x 95%)/26.50
= 941.04 pieces
In Day3 production capacity (line efficiency 45%)
= (10 x 60 x 125 x 45% x 95%)/26.50
= 1209.91 pieces
Day4 onward projected line capacity will be (line efficiency 50%)
In Day3 production capacity
= (10 x 60 x 125 x 50% x 95%)/26.50
= 1344.34 pieces
Daywise total production capacity from 4 lines and cumulative production is shown in the following table. In the last day, lines don't need to work 10 hours to stitch the balance quantity.
Table: Daily capacity calculation 
From the above calculations, 4 lines need to work for 8 days to produce 35,000 pieces of an order.
Related Post: How to calculate the production capacity of a garment factory?
Related Post: How to calculate the production capacity of a garment factory?
In the above calculations, there is a slight error. In place of 6, it should read as 60. Kindly correct
ReplyDeleteHi Vivek, thank you for finding and informing the mistakes. Correction is done.
DeleteWhy do you multiply in 60, where did you get it?
DeleteHi, 60 is multiplied in the above calculations to convert hours into minutes. Factory works 10 hours a day, which is equal to 600 minutes. Reason, the product SMV is in minutes. We are dividing the total available minutes by garment SMV to calculate production capacity.
DeleteI am interested on calculation the cutting room production capacity in minutes, separatly for all cutting tools and the number of workers .
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