A few years back, I learned a valuable lean lesson- "Don't ignore your water spider." A water spider is the name given by our Japanese sensei (teacher) for a material handler or stock person. While I was working with the stretcher assembly line at Hill-Rom, the world's leader in manufacturing hospital beds, we faced tremendous growth and change. The stretcher production was scheduled for six new model releases, one every six to eight months, to run down the same final assembly line. Our sales were steadily climbing. The line balances/standard work content along with the department layout was in constant "change" mode to keep up the dynamic conditions caused by the new product introductions and growing production requirements.
Several lean techniques were used to meet these challenges like conducting multiple kaizen events, running 3P events (Production Preparation Process), right-sizing assembly stations, kiting of component delivery, production smoothing, using supermarkets and point of use locations, etc. For the most part, the improvements to the manufacturing process kept pace with the rapid changes.
In the midst of all this change, I focused mainly on the "waste elimination" of the direct labor piece and gave little attention to any indirect labor activities. The line was set up for the water spider to present the material to each line operator to maximize the direct labor work content on building the stretchers and not on getting their own stock. The component stock levels for each workstation ranged from 5 pieces to daily replenishment while the main line was one piece flow with mixed models. As the line grew in size and complexity, so did the work load of our water spider.
It didn't take too long for our water spider to start complaining that she couldn't keep up and was completely wore out by the end of the shift. The operators on the assembly line also complained that the water spider wasn't doing her job, so many times they ended up getting their own stock. The frustration on the line was growing as fast as our sales.
That week, I worked with our water spider to clearly define her standard work load. For every workstation on the assembly line, I created a spaghetti diagram of the stock replenishment path to the supermarket location. It was a mess! Our water spider even wore a pedometer to log the typical distance she traveled. She clocked over 18 miles on one shift! No wonder she was wore out at the end of each day.
Her frustration with the job was so high that she was not willing to offer any suggestions for improvement and just wanted to bid out to another department. Our water spider told me that fancy charts and spaghetti diagrams could never show how difficult it was to do her job and that I should walk a day in her shoes to really understand her problems. So I did. Since she was scheduled for vacation the following week, I decided to assume her duties for the week pending approval by the union and my boss. With a little persuasion, both the union and my boss gave me the green light.
Our water spider agreed that I could make any improvements to her current standard work while she was out, anything would be better. Upon her return, we would modify any of the changes if needed. She left on vacation laughing and wished me "Good luck, you'll need it!"
My first day as a water spider, I felt like I had a target on my back. None of the assembly line operators stocked any of their components that day and yelled at me, with great joy I might add, to hurry up, they were out of this part or that part! Even the line supervisor took particular pleasure in yelling at me to do my job and not hold up the line. I was running around as fast as I could just to keep up with no thoughts of following any standard work. It was pure survival mode. I could not wait for the shift to end! By the time the shift did end, my entire body ached and I really understood the material handling problems. It was going to gemba (actual place) to the extreme. I also became a true believer of the lean thinking to make it easier, better, faster and cheaper (in that order).
After the first day, no matter what, I was not going to give up or suffer through another day like this one. During the breaks and lunch, I did manage to organize my ideas on what needed changed first. With all the previous line changes, the supermarkets for many of the components were now located too far from the point of use. Also, many of the drop stock location were not placed correctly. The spaghetti diagrams showed it but after working as the water spider, I now felt it. I stayed late that first night making several improvements.
The second night was little better and I quickly evaluated the improvements from the night before. Later that second night, I made more improvements. Each day, I continued the cycle of experimenting with the improvements and making adjustments to see what worked best. By the end of the week, my pedometer reading hit only 10,000 steps or five miles and not one line operator had to get their own parts or screamed for me the entire shift.
When our water spider returned, I spent the day with her demonstrating all the improvements. Although she did not like all the changes, she greatly appreciated the overall improvements in her new standard work. The best change was that she started freely expressing her ideas for additional improvements. By improving her standard work to the point that she could manage it, the dread for her job shifted to one of greater satisfaction.
My mistake was that I did not pay enough attention to the standard work of our water spider and concentrated on the direct labor work. Yes, even indirect work activities should have standard work. Based on lean teachings, we should eliminate waste everywhere and remove burdens of ALL employees. The support functions of material handling should not be ignored. The same can be said for maintenance, tooling, etc. Strong, efficient support functions go a long way to improving the flow of the value stream.