Tips

If you ask a web guide manufacturer that question, be careful considering their answer. Keep in mind that it is impossible to know how accurate a web guide system is without knowing the amount and more importantly the rate at which the error enters the web guide system.

Getting back to basics, all webs move side to side while moving through any converting process. The movement may be a slight few thousandths of an inch; it may be a drastic few inches. The amount of movement may have no or very little affect on certain processes. However, certain other processes may be greatly affected or web wandering may cause great amounts of material waste.

Whichever the case is in your operation, make no mistake, all web "wander" from side to side as they run through an converting process. This web wander has many possible causes; inherent web camber, misaligned rollers, roller deflection, web gauge band variations, tension fluctuations, air entrainment in webs, machine vibration and many others.

Web guide systems simply detect your webs position and attempt to move it back to its proper position if they see web wander. Many people will immediately ask the question, "Well, how accurate is your web guide system" to a web guide manufacturer and that is a perfectly legitimate question, especially when your process is dependent on web position accuracy. However, keep in mind, web guide accuracy can only be calculated if the amount and rate of error is known. You MUST know how much your web wanders how fast it wanders in order to calculate any web guide systems level of accuracy.

For example, does your web wander +/- 1" maximum or +/- 6" maximum? And does it wander +/- 1" in one second or does it take three seconds for it to move that much? These are questions you should know the answers to in order to calculate your web guide systems accuracy.