Some Essential Formula and Example for Industrial Engineer (IE)
Industrial engineering is a branch of engineering which is used to eliminate waste of time, money, materials, machine time, energy, person-hours, and other resources that do not generate value. As like other manufacturing industry, industrial engineering now widely used in textile and apparel industry. Textile and garment industry have to face heavy challenges due to various factors including global competition, production costs increase, less productivity/efficiency, labor attrition, etc. For overcoming those challenges industrial engineering knowledge and formulas are frequently used in apparel manufacturing industry. In this article I have given some important and popular terms and formulas of industrial engineering. I have also given some examples for which reader can easily understand.
Some Important Formula & Example for IE
1. Standard Pitch Time (S.P.T) = Basic Pitch Time (B.P.T) + Allowances (%)

· GSD = (Man power * Work hour) / Target
· SMV = Basic time + (Basic time * Allowance)
· Basic time = Observed time * Rating
· Observed time = Total Cycle time / No of cycle
· Rating = (Observed Rating * Standard rating) / Standard rating
· Efficiency = (Earn minute * Available minute) * 100
· Earn minute = No of Pc’s (Production) * Garments SMV
· Available minute = Work hour * Manpower
· Organization Efficiency = (Basic pis time / Bottle neck time) * 100
· Basic pis time = Total GMT SMV / Total Manpower
· UCL = Basic pis time / Organization Efficiency
· LCL = 2 * Basic pis time – UCL
· Capacity = 60 / Capacity time in minute
· Cycle Time = 60 / Team target
· Capacity Achievable = Capacity * Balance
· Daily output = Work hour / SMV
· Factory capacity = (Work hour / SMV) * Total worker * Working day * Efficiency
· CPM = (Total over head cost of the month / No of SMV earners * Work minutes) *Efficiency
· Required no of operator = Target daily output / Daily output per operator
Example:
1. Efficiency = Output/Input
= (SMV*Product Quantity) / (Worker*Working Hour*60)
= [(38.50*700) / (60*10*60)]*100
= 74% (Line Efficiency)
Here,
SMV=38.50
Working hour=10
No. of worker=60
2. Target/hour = (60/SMV)*Efficiency%
= (60/0.85)*70%
= 50 pcs/hour
Here,
SMV=0.85
Efficiency=70%
3. Target/line = [(No of worker*working hour*60)/SMV]*Efficiency%
= [(75*10*60)/23.5]*60%
= 1150 pcs
Here,
No of workers=75
Working hours=10
SMV=23.5
Efficiency=60%
4. Required days for the schedule = Total order quantity/Average target
= 50000/2000
=25
Here,
Average target=2000
Order quantity=50000
5. CM of garments= (Total Production)/(no of worker*work hour)
= 250000/(1500*10)
=1.66 BDT
Here,
Total Production=250000
No of workers= 1500
6. Factory capacity = [(Work hour*total workers*working day*60)/SMV]*Efficiency
= [(10*1500*26*60)/14.13]*55%
= 828025 pcs/month
7. Line GSD/day = (Manpower*work hour)/target
= (50*10*60)/900
= 33
Industrial engineering is a branch of engineering which is used to eliminate waste of time, money, materials, machine time, energy, person-hours, and other resources that do not generate value. As like other manufacturing industry, industrial engineering now widely used in textile and apparel industry. Textile and garment industry have to face heavy challenges due to various factors including global competition, production costs increase, less productivity/efficiency, labor attrition, etc. For overcoming those challenges industrial engineering knowledge and formulas are frequently used in apparel manufacturing industry. In this article I have given some important and popular terms and formulas of industrial engineering. I have also given some examples for which reader can easily understand.
Some Important Formula & Example for IE
1. Standard Pitch Time (S.P.T) = Basic Pitch Time (B.P.T) + Allowances (%)

· GSD = (Man power * Work hour) / Target
· SMV = Basic time + (Basic time * Allowance)
· Basic time = Observed time * Rating
· Observed time = Total Cycle time / No of cycle
· Rating = (Observed Rating * Standard rating) / Standard rating
· Efficiency = (Earn minute * Available minute) * 100
· Earn minute = No of Pc’s (Production) * Garments SMV
· Available minute = Work hour * Manpower
· Organization Efficiency = (Basic pis time / Bottle neck time) * 100
· Basic pis time = Total GMT SMV / Total Manpower
· UCL = Basic pis time / Organization Efficiency
· LCL = 2 * Basic pis time – UCL
· Capacity = 60 / Capacity time in minute
· Cycle Time = 60 / Team target
· Capacity Achievable = Capacity * Balance
· Daily output = Work hour / SMV
· Factory capacity = (Work hour / SMV) * Total worker * Working day * Efficiency
· CPM = (Total over head cost of the month / No of SMV earners * Work minutes) *Efficiency
· Required no of operator = Target daily output / Daily output per operator
Example:
1. Efficiency = Output/Input
= (SMV*Product Quantity) / (Worker*Working Hour*60)
= [(38.50*700) / (60*10*60)]*100
= 74% (Line Efficiency)
Here,
SMV=38.50
Working hour=10
No. of worker=60
2. Target/hour = (60/SMV)*Efficiency%
= (60/0.85)*70%
= 50 pcs/hour
Here,
SMV=0.85
Efficiency=70%
3. Target/line = [(No of worker*working hour*60)/SMV]*Efficiency%
= [(75*10*60)/23.5]*60%
= 1150 pcs
Here,
No of workers=75
Working hours=10
SMV=23.5
Efficiency=60%
4. Required days for the schedule = Total order quantity/Average target
= 50000/2000
=25
Here,
Average target=2000
Order quantity=50000
5. CM of garments= (Total Production)/(no of worker*work hour)
= 250000/(1500*10)
=1.66 BDT
Here,
Total Production=250000
No of workers= 1500
6. Factory capacity = [(Work hour*total workers*working day*60)/SMV]*Efficiency
= [(10*1500*26*60)/14.13]*55%
= 828025 pcs/month
7. Line GSD/day = (Manpower*work hour)/target
= (50*10*60)/900
= 33