Metalforming Electronics



PML: Process Monitoring & Lean

Friday, February 1, 2008
The partnership of lean manufacturing and process monitoring is inseparable in the best manufacturing companies. Yet, many metalforming facilities cannot seem to justify the real-time monitoring of their manufacturing processes as a serious tool toward the implementation and maintenance of lean manufacturing. I would like to propose a new acronym to help address and overcome this unnecessary separation of these two extremely important approaches to manufacturing. I suggest that “PML” be used to describe the process that a manufacturing company uses when it has simultaneously both process monitoring and lean as its core competencies.

Who doesn’t want to have a lean manufacturing company? It would be foolish in this competitive economy to argue with the need for efficient operations throughout the plant. But how to minimize wasted motion, energy, labor and time? Where to start? Well, you might start with the gross waste that seemingly pervades the entire shop area. Read a few good books on the topic, perform their recommended mathematical exercises and voila! The areas that can be “leaned” become obvious. But why are these chosen areas so inefficient? Surely they are wasteful, but why? Why is so much labor and time spent on such seemingly insignificant motions?

I suggest that in parallel, if not before a lean program is implemented, the machinery and tooling that produces the parts be monitored. This is the classic process-monitoring conundrum—the chicken and egg of automation. What comes first, lean or process monitoring? The answer lies in how you define process monitoring in a metalforming and assembly operation. To the nontechnical crowd, it means primarily monitoring people. To the technical folks, it means monitoring the tooling and machinery. It actually means both—the hardware and the personnel of the manufacturing process should be monitored during implementation of lean practices. What are the basic steps for process monitoring and partnering it with a robust lean program?

Step 1—The past two years have seen a flood of superb new process-monitoring hardware and software for the stamping areas of the company. There are excellent controls and associated software packages from companies that specialize in the monitoring of dies, tooling, presses and other forming equipment. With a minor hiccup or a major die crash, the technology records the event with specificity and sends out alerts throughout the company’s computer network. Likewise, some of these companies offer in-die part-measuring capabilities as part of their process-monitoring portfolio. All active dies and presses over time should be instrumented with sensors, controls and process-monitoring software.

Step 2—The tooling and machinery in the secondary or value-added portions of the company should have all critical mechanical hardware monitored. This includes single-stroke tooling and welding machinery (manual or automatic), and equipment and tooling related to riveting, staking, stud insertion, tumbling, painting, plating, etc. These areas of the company can be monitored with personal computers (PCs) at each of the machines. These PCs track, record and alert those with a need to know the status of all manufacturing processes in the value-added streams. A robot (or stud inserter or nut welder or paint-line conveyor) malfunctions and all pertinent technical and managerial areas of the company are automatically alerted with details about the malfunction by a process-monitoring PC attached to the troublesome manufacturing process, which in turn reports to manufacturing-management software.

Step 3—Implement a company-wide manufacturing tracking and planning software package. Find the appropriate vendor of such software who speaks your specific manufacturing language, has a solid track record with other metalforming and assembly companies, provides thorough training and, most importantly, has the patience to help your company transition from little handwritten notes, spreadsheets, e-mails, innuendo, gossip, gut feelings and emotionally charged production meetings to calm and tranquil manufacturing decision-making processes based on real-time shop-floor data, reason, logic and science.

Process monitoring and lean go hand-in-hand. Once armed with the real-time data that the three steps listed above provide, it becomes much easier to implement lean down from the individual punch level and out to the logistics of shipping.

I, like many, made a New Year’s resolution to lose weight, i.e. become lean. Where did I start? By using a sensor, control and display—my weight scale—to let me know where I began, and allow me to track my progress and, hopefully, achieve ultimate success. A modern factory wishing to fully and thoroughly implement a lean program likewise must have instrumentation at its side. MF


Visit Our Sponsors