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An Accidental Lesson in Surface Mount Technology Manufacturing

Posted by Greg Caswell on May 23, 2017 9:21:00 AM

Surface-Mount-Technology-Manufacturing.jpgRecently I presented What 45 Years in the Electronics Industry Has Taught Me at our annual Design for Reliability Conference, and it got me to thinking about the “fails” I experienced during my career that are funny today but not necessarily when they occurred. They also taught me some lessons you may find valuable. Indulge me while I recount one of the more memorable stories.

In the earliest days of Surface Mount Technology (SMT) manufacturing in the late 1970s I had set up one of the first manufacturing lines in the country. One of the pieces of equipment on the line was a batch mode vapor phase reflow soldering system that boils a fluoroinert material to a temperature of 215°C and releases vapor into a chamber outfitted with cooling coils with water running through them. The fluoroinert vapor hits the cooling coils and condenses back into the vapor zone. To solder, you lower an elevator with your assembly on it into the vapor and it condenses on the assembly and reflows the solder joints all at once. Condensation from the cooling coils falls into a trough below the coils and is sent down the drain of the manufacturing facility.

The system had been installed to the letter of the manufacturer’s instructions; however, neither the manufacturer nor I thought about what would happen if the drain in the building clogged. And it did.

The trough filled with water from the condensation and overflowed into the 215°C vapor zone when the drain backed up. When the water hit the vapor there was a loud “BOOM!” and 215°C vapor was pouring out of the front of the system.

I ran into the assembly area, witnessed the aftermath, and knew I needed to turn that equipment off quickly before someone got hurt. While scrambling across the room, I realized that I had zero traction as the fluoroinert material was all over the floor. A hastily hatched Plan B had me turning off the unit and then ducking under the vapor. I was feeling pretty accomplished as I stood up on the other side of the vapor, still skimming across the floor quickly – right up to the point when I slammed into a sheetrock wall.

You’ve all seen Wile E. Coyote after he crashes into a mountainside and imprints it with an outline of his entire body…yeah, that was me.

As you might imagine, I found no humor in the situation then. Now, I can’t help but smile. Moreover, I walked away with a bit of practical wisdom: When implementing a new piece of equipment or process, it’s important to develop contingency plans for different scenarios so that if problems arise, action steps are already in place to deal with them.

There are plenty more laughs and lessons I want to share, so subscribe to the DfR Solutions blog and keep checking back for more of what 45 years in the electronics industry has taught me.

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Topics: Equipment Setup