ABSTRACT

Now that the time studies have been done, an analysis of the nonvalueadded work should be conducted. Many manufacturers operate under tremendous levels of waste. The data on the time study collection sheet will provide all the necessary information to begin process improvement ideas. Although WIP (work in process) is not captured during time studies, WIP is very common in today’s assembly processes. The closer a company can get to a single piece flow operation, the more proficient they are in running a lean operation. WIP will only create moments of waiting for the operators. Operators may forget which unit they are working on, forget to install parts, or forget to perform essential quality tasks. The main assembly process for the electric bike will be designed for single piece flow, as that is the ideal. In Chapter 4, I discussed the difference between takt time and cycle time. Takt time is the rate at which a single piece flow line must move. Therefore, takt time and single piece flow go hand in hand. Excessive building of WIP has no rhythm, but when establishing single piece flow, the following factors should be considered:

Cycle time versus takt time

Equipment constraints

Changeover time

Material optimization

Cycle Time versus Takt Time

Is the cycle time of a workstation or work cell more than takt time? If the nonvalue-added work has been eliminated and the cycle time cannot be reduced, then single piece flow will be difficult to implement. A good exam-

ple is the speed of a saw. Saws and other equipment are set at a maximum capacity, and the rate at which parts are cut may be more than takt time.