The time standard to make the valve shaft is 50 pieces per hour. If the shop works at the rate of 80%, how many people would be required to cast 1,200 valve shafts per shift (8 hours)? If 50 minutes downtime is allowed per day, how many people are needed?
Case 1: without 50 minutes downtime:
(1) How many pieces do we need to make per shift?
(2) How many EFFECTIVE minutes does one shift have?
(3) Takt Time = Effective time during a period / Total quantity during a period
(4) How many pieces can be produced in one shift under effective time?
(5) How many people are needed = How many pieces do we need to make per shift / How many pieces can be produced in one shift under effective time.
Case 2: After 50 minutes downtime is considered:
How many EFFECTIVE minutes does one shift have?
Effective minutes = Nominal minutes – Downtime) × Efficiency