Broken Welds
A manufacturer of mountain bicycles designed an automated system for welding bike frames. For three years, the system worked nicely, handling about 1000 frames per shift. Production was scheduled for two shifts per day. The system was designed to weld the frame and then to check the quality of each weld. The welded frames were then transported to another plant for assembly.
Recently, a few of the frames had failed. Careful testing showed that a foreign substance in the welding rod purchased from an outside vendor possibly contributed to the failure. When checked, however, the rods conformed to the specifications given to the Purchasing Department and guaranteed by the vendor. The Chief Engineer ordered the Production Department"s Project Leader, Alison Passette, to create a project immediately to find out precisely what was causing the failures and to find a way to solve the problem. This project was to take priority over all other projects in the department.
Alison was familiar with the Chief Engineer"s tendency to overreact to any glitches in the production process, so she decided to determine the impact of the proposed project on all the other projects in the department. She also discussed the problem with Ken Kelsey, one of her welding experts, who felt sure he could solve the welding problems by determining what foreign substance, if any, caused the problem. He could then set up a system to detect the presence of the substance and reweld the affected frames. Of course, he added, they would also have to change their specifications for the welding rod to eliminate the chemical responsible for the failures.