Situation Downtime is a production and profit killer for companies. In the February brain teaser, Patrick, a supervisor at a large manufacturing company, was asked to develop a method to measure downtime in a three-step production process. Patrick developed a plan to collect data on downtime, and its causes, and then analyze the data for the plant manager’s use. After the first set of data was collected, Patrick discovered problems with the means in which the data were summarized and analyzed. His initial test protocol tracked downtime for each step and then combined those times to determine how much time was lost in a day. The methodology appeared correct, but in practice the plan didn’t work as anticipated. After talking with the supervisors overseeing the three separate production steps, Patrick realized that the data reflected the cumulative effect of downtime. While the data from step 1 could be used without modification, the downtime recorded for steps 2 and 3 included the lost production time incurred during that particular step, as well as the lost time that occurred during preceding steps. To understand the downtime behavior resulting from the causes in each separate production step, only those minutes of downtime recorded for reasons specific to each step would be summarized. The supervisors would continue to collect downtime for causes in the previous step, but each step’s downtime would be tracked independently. For the daily total, the downtime data from step 3, in addition to the downtime from the previous steps, can be used to represent the process’ total downtime. Available data In the table, Revised Data on Downtime, the data from Plant 15 was collected for 10 days according to Patrick’s new instructions. The downtime for each step in the process is given along with the total. Also, the length of the working day is given. Questions 1. Use the data to prepare an analysis of downtime for the supervisor in each of the three process steps and for the plant manager. 2. Interpret the behavior of the downtime for each step in the process that will result from causes in that step. 3. How can the supervisors in each step use the analyses of downtime data to reduce downtime?
Published by QualityMagazine. View All Articles.