In my earlier post about Takt Time, I discussed the need to account for downtime on a production line. This downtime could be related to lunch, breaks, 5S cleaning, or any other reason an employee might not be at their workstation. In most U.S. manufacturing facilities, the typical amount of time allotted for this downtime is around 15 – 18 percent. Generally, these small breaks do not cause too much disruption if there is someone else to temporarily fill in for them. In Lean production however, the objective is to maintain a continuous flow of production. To do this requires that machines continue to run, materials and products continue to move, and there is always someone available to fill in.
For every 3 to 4 rotary machines, I assigned one Setup; a person assigned to maintain the machines in the event of a failure. (The machines were fairly old, but were well maintained, however, any machine that is run 24 hours per day, 7 days a week is going to encounter problems.) When I first started working at this facility, I was told that production on my shift had plummeted and there was dire need for improvement. I noticed immediately that one of the biggest reasons for the shortcomings in production was that when an operator was not at a machine, that machine went down. For a company that produced more than 6 million needles and syringes per day, I was very surprised they did not have a plan in place to account for missing operators. This became one of my first objectives.
To institute Continuous Flow was simple. All that was needed was a plan to keep the machines running as close to 100 percent of the time as possible. For every machine, there was one Operator, and for every four machines, there was one Setup. I created work cells based on the four-machine assignments of the Setups. Each of these work cells had five people; 4 Operators and 1 Setup. When it was time for an Operator to take a break, the Setup would fill in for them. Three or four Operators from different work cells would take their breaks together, and the Lead Setup that was not assigned to any machines would fill in for the other Setups when it was time for their breaks. It took only one day for the plan to catch on, and actually led to another benefit…
When I first started, I found that Operators had set up “clicks” and friends selected machines based on their proximity to other friends. The result was that there were groups of friends running machines next to one another and it led to reduced efficiencies and production due to socializing. Shortly after making the change to Continuous Flow, these friends purposely started requesting assignments on machines in other work cells so they could take their breaks with their old friends. The result was that the Operators worked together more fluidly, got to know more coworkers outside their little clicks, and eventually started working as one big team with much higher job satisfaction as the heat on them had been reduced because the production numbers had increased dramatically.