End and center pivot guides do not displace the web, they only have the angle of rotation to reposition the web. This makes them very slow in term of response, and therefore, are not an ideal choice in web guiding options.
Within the group of terminal web guide systems, there are two basic types: Unwind web guide systems and rewind web guides systems.
Both systems have basically the same components, but they work differently. Let’s look at the unwind web guide structure.
However, even though we mention four main components, the web has to be considered a component of the web guiding system.
This rule states that a web approaching a roller will align itself perpendicular to the axis of rotation of the roller. The Normal Entry principle accounts for one of the most common defects in a converting line, roller misalignment. If your converting line has one roller that is not correctly aligned perpendicularly to the required path of the web, the web will move in order to be perpendicular to the misaligned roller.
In our previous post on web guiding fundamentals, we mentioned the terminal web guides. These are web guides that are found at the start or the end of the process. Their location is usually on an unwind or a rewind stand. As we discussed, their installation depends on whether the guiding system is used for unwinding a roll of web or rewind a processed web into a roll.
Imagine having several converting lines with old web guide systems that were starting to fail. Worst of all, the suppliers consulted could not offer them replacement parts since this equipment was no longer manufactured. It seemed like the only option was to buy complete new units.
It's an advantage to know what you are dealing with when aligning your web as it enters your converting process or is being wound into a processed roll. Here's some information that should be of help to you.
Trade shows hit a huge speed bump with all the restrictions caused by Covid-19. We just didn't know if people were going to attend or if exhibitors would participate. In talking to partners and customers we found that this was a variable that was up in the air.
A customer once asked us why would you need web guiding on a brand new machine? Their point of view was that the machine was state of the art, the web guide didn't move at all during operation, and they didn't see any problems with their materials. Well, our answer was that there are four main reasons why any converting line requires web guides.
At first, you manage to work with the deficiencies they have.