I have seen more drive problems in the last two YEARS than I have seen in my first two DECADES in the industry. When I first started in the paper industry, it would be unusual to work on more than one or two troubled drives in a year. New designs and particularly automation were what was giving us fits beyond the usual headaches of ever-increasing demands for quality and productivity. True, the paper industry has much better equipment and technical resources. However, they also have far more demanding applications.

At speeds approaching 10,000 fpm running tender materials like paper, you just can't afford to have a web break. But even when I started working in the converting industry as a consultant more than a decade ago, drive assignments were not all that common. Now, I am working on truly troubled drives every month. Drives that disable the process so much as to risk shutting down the line permanently due to spurting blood loss out of waste and delay arteries.

Perhaps it is my imagination. Perhaps it is just the reflection of a small sample size of but a single person's perspective. However, I don't think this is the case. I truly believe that tension control has risen to be one of the biggest of the web handling issues and a major contributor to waste and delay. Perhaps only wrinkles and winding problems surpass tension as overall causes of web handling troubles in our industry. However, both wrinkles and winding are very tension sensitive, so that we probably underestimate its importance.

Maybe it is just that our equipment is aging and the current economy not longer allows proper maintenance. I am sure this is true on occasion. However, as a general case this does not make sense for two reasons. First, the incidence of troubles jumped, as opposed to ramping up as might be predictable if equipment were wearing out. Second, this jump seemed to have begun well before the current economy.

Maybe it is because we have better instrumentation and can detect problems more easily. Load-cell readings and even meters for dancer position make tension variations easier to detect than watching or feeling the web. However, I don't believe that this is the case either. As much as I would like to believe the preachings and teachings of web handling proponents are taking hold, we can not take credit for a jump in sensitivity to tension control. The calls I get are not "Help, my load cell reading is moving more than 10 percent when I change speed." It is more like "Help, my web is being ruined, my machine is shutting down and/or my customer is complaining that..."

In other words, tension is not varying beyond the textbook 10 percent. Rather, it is varying 100 percent and wrapping rollers or putting a puddle of web on the floor. You don't need a load cell to detect this. It is a pragmatic rather than theoretical concern that is driving people to call me about drives.

Maybe it is because we are more sensitive to waste, delay and customer complaints. However, I have trouble buying into the first two reasons. People are so busy that they can't even track waste and delay properly, much less have the time to go after higher hanging fruit. They are just trying to keep their heads above water. It is possible that increased sensitivity to customer complaints and increased demands of the customer could be a driving force for drive attention. There is a lot of excess machine capacity out there and a material buyer does not have to put up with what they might have before the new economy. Some material suppliers are scrambling just to keep their customers and will do things they never did before: call for expert help when in-house resources and suppliers have all come up short.

I am thus left to conclude that we SEEM to be having more drive troubles because we ARE having more drive troubles. Next month I will offer my opinions as to why this is so.

David Roisum, Ph.D. Consulting Technical Editor, 920/725-7671 DRroisum@aol.com, www.roisum.com