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So far we have discussed the different types of web guiding systems for converting applications. You now should know the different types of web guiding systems, and their design and installation recommendations. Also, you should have an idea of why web guiding is needed and where they should be installed in converting operations. In this blog post we will address a component of a web guiding system, the web guide actuators.

End and Center Pivot Guides - Not a commonly used web guide in the industry

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.

Steering web guides are part of the intermediate web guide group.

These differ from the displacement guides in that they don't have a guide span made of two rollers. Steering web guides will typically have one guide roller installed on two raceways at an angle so the roller moves in an arc. The roller upstream from the steering roller is fixed. This arc movement provides the steering of the web.

Displacement Web Guide - The most commonly used

Within the group of intermediate web guides, we find the displacement web guide or off-set pivot web guide. For any web guiding application we would recommend this type of web guide as a first choice. One of the main reasons for this recommendation is this type of web guide actually displaces the web without bending the web.

Unwind and rewind web guide systems are used at the start and end of the converting lines. That is why they are referred to as terminal web guides. So, what is required to properly incorporate a terminal web guide in your converting line based on web guiding fundamentals?

Rewind Web Guide Structure

In a previous blog we discussed the unwind web guide structure. Typically, these are made up of a shifting stand, an actuator to move the shifting stand, a fixed sensor mounted on the fixed base of the machine between the last shifting idler roll and a fixed roll, a controller, and of course, the web. Today we look at the rewind web guide structure.

We are often asked by our customers to let them know if we can sense or edge guide a certain material. This is how this usually goes:

We have a difficult to sense material. It is very porous, non-homogeneous, extremely translucent... Do you think your web edge sensor can see the material and guide the material?

And our answer typically is, yes we can.

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.

A web guiding system for converting operations has four main components:  

• Guide Structure/Mechanism
• Actuator
• Sensor
• Controller

However, even though we mention four main components, the web has to be considered a component of the web guiding system.

Most web guides work on the fundamental principle of Normal Entry.

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.