An average of 30 new batches of parts are produced in a fact

An average of 30 new batches of parts are produced in a factory each month to meet the monthly demand. On average, a batch consists of 60 parts to be processed through 10 machines. The operation time per machine per part is 15 min. The non - operation time per batch at each machine averages 8 hours, and the required setup time per batch at each machine is 4 hours. Set up is done one machine at a time. During its regular shifts, the plant operates 160 hr/month and there are 20 machines in the factory. Manufacturing Lead Time (MLT) for an average part Average Production Rate (R_p) of a machine Plant Capacity on a monthly basis (PC) Utilization of the plant (U%) Do you think Overtime has been authorized in order to keep up with the demand? Explain. Average level of Work - in - Process (number of parts in process, WIP) Work - in - Process ratio (WIP Ratio) assuming 20 orders each consisting of 50 parts manufactured in 160 hours per month. Time - in - Process ratio (TIP Ratio)

Solution

Gven,

Operation time per machine per part =15min = (15/60)hr =0.25hr

Non-operation time per batch at each machine = 8hr

setup time per batch at each machine = 4hr

a) Manufacturing Lead Time (MLT) = 10(4+(60x0.25)+8) = 270hr

b) Tp = (4+60x0.25)/60 = 0.3167hr/pc

So, Avg production rate of a machine = Rp= 1/Tp =1/0.3167 = 3.157 pc/hr

c) Plant Capacity = (160x20x3.157)/10 = 1010.24 pc/month

d) Parts launched per month = 30x60 =1800 pc/month

Utilization = 1800/1010.24 = 1.78 =178%

e) Schedule exceeds plant capacity by1800-1010.24 = 789.76 pc

This requires overtime in the amount = 789.76x10x 3.157= 24932.72 hr

f) WIP = 270x1010.24x1.78 = 485527.344 parts