ABOUT WEBEX INC.

Frequently Asked Questions

Do you offer OEM discounts?
Where are your price breaks?
Is the shipping crate included?
What are your standard lead-times?
Is freight included and what is the cost of shipping?
What is the difference between a dead shaft and live shaft idler?
What is the finished diameter of the idler rolls?

What type of bearings do you use and how do I purchase replacements?
What is the difference between static balance and dynamic balance?
How is balance correction done?
How are roll designs determined and why can't I use a smaller roll diameter?
How do I pick the correct roll for my application?
Is a vacuum roll a cleaning device?
When is it appropriate to use a vacuum roll?

1.Do you offer OEM discounts?

Yes, OEM discounts are tailored to accommodate customer's requirements.

2. Where are your price breaks?

Put simply, the higher the quantity the better the price. The most significant price differences will be in the lower quantity ranges like from one to two. As a general rule of thumb use the following quantity brackets: (1), (2), (3-4), (5-10), (11-20), (21+)

3. Is the shipping crate included?

Unless otherwise specified, the shipping crate is included in the price.

4. What are your standard lead-times?

Lead-times are always flexible and vary widely by product and current workload. Most standard idler rolls can be shipped within 10 days, while custom precision rolls will take additional time. For emergencies, use our "Web-EXpress 48-hour" service. We will do whatever it takes to respond to your delivery needs. We'll always give you an honest answer so call to get the most current information on lead-times.

5. Is freight included and what is the cost of shipping?

Because of the wide range of shipping options available, our products are usually quoted FOB our plant. If requested, we are happy to estimate and include the cost of freight in our price. We always search for the best value in shipping options and can have your carrier bill your company direct or we can prepay the charges and add them to our invoice.

6. What is the difference between a dead shaft and live shaft idler?

A dead shaft roller has internal bearings where the roll body spins around a stationary (dead) shaft. A live shaft roller has externally mounted bearings where the roll body and journals spin together.

7. What is the finished diameter of the idler rolls?

"Nominal diameter" means that we use that size of raw material and machine the surface to a clean, precision surface. A longer tube will require more stock removal than a shorter tube for clean up. For consistency Webex usually finishes aluminum rolls at 0.100" under the stated nominal diameter and steel rolls 0.050" under the stated nominal diameter. In other words, on a 6"nom dia aluminum roll would finish at 5.900" and a steel roll would finish at 5.950" diameter. Note that custom or held size diameters can be produced whenever required.

8. What type of bearings do you use and how do I purchase replacements?

Webex uses special OEM bearings made especially for application in our idler rolls. The bearings are fitted with a non-contact shield, have increased diametrical clearances and are filled only 25%-30% with grease. All of these features offer the benefit of free running performance as well as the ability to operate at temperatures up to 350F. All sizes of Webex bearings are kept in stock at our plant. They are reasonably price and are sold as replacements into our idler rolls in the field.

9. What is the difference between static balance and dynamic balance?

When a roll is in static balance it usually implies that it is balanced to "zero rotation" where it is sufficiently balanced so that when placed in low friction bearings, it will not rotate due to imbalance. Static balancing is often specified on lower speed applications; usually less than 400 FPM depending on roll diameter and weight. When a roll is dynamically balanced, it is rotated at or above the design line speed and the imbalance is measured by and corrected in the balancing machine. There are established ISO balance tolerances which are a function of the roll mass and RPM.

10. How is balance correction done?

Balance correction is done by either adding or removing weight until the desired balance tolerance is achieved. Weights are usually attached to the inside of the roll, by welding, mechanical fasteners or high performance adhesives. Webex rolls never have balance weights attached to the outside of the roll. Weight is removed by either milling or drilling. To be done correctly, balancing is often done in a multiple step process involving more than one correction method.

11. What is Hardcoat and what is Hardlube?

Hardcoat is an anodizing process that produces a very hard, abrasion and corrosion resistant coating on aluminum. The surface of the aluminum is transformed to aluminum oxide. This coating becomes part of the base metal so it will not flake off. Hardcoat has a surface hardness of 60-70 Rc. Hardlube is Hardcoat with Teflon introduced as a release agent. See others in coatings and platings.

12. How are roll designs determined and why can't I use a smaller roll diameter?

Rolls are analyzed based on their application, which includes face width, speed and loading (either by web tension or nip load). An analysis will compare such things as anticipated stress and deflection levels to acceptable values and critical speeds to operating speeds. If any variable is not at an acceptable level, the roll construction needs to change. Diameter increases are often the most effective way to avoid undesirable stresses or deflection when compared with working with high strength materials which may be much more expensive.

13. How do I pick the correct roll for my application?

First, determine if a dead shaft (roll body rotating around a stationary shaft) or a live shaft (journals mounted in external bearings) is right for the job. Dead shaft rolls are versatile and easy to mount while live shaft rolls are generally better for more demanding applications such as high loads, elevated temperatures or harsh environments.
The dead shaft aluminum roll is the "workhorse" of idlers. It's lightweight and inherent corrosion resistance gives it exceptional performance over a broad range of applications.
For economy, strength and high performance a steel dead shaft is a good solution and has been an industry standard for years.
For strength and corrosion resistance consider stainless steel dead shaft rolls.
Lightweight aluminum idler rolls have the same features as standard aluminum idler rolls but with about half the weight. Use Lightweights when a free-running, low-inertia roll is needed.
UltraLight Aluminum and FeatherLight carbon fiber rolls are recommended when web wraps and web tensions are limited, as they provide the lightest weight and lowest break-away torque available. Carbon fiber rolls are particularly well suited for wide and high speed applications.
For higher loads, elevated temperature or harsh environments consider Live Shaft Aluminum, Live Shaft Steel or Live Shaft Stainless Steel idler rolls.

14. Is a vacuum roll a cleaning device? When is it appropriate to use a vacuum roll?

A vacuum roll is used for tension isolation, similar to a nipped pull roll or "S"-wrap rolls. A vacuum roll offers the advantage of touching only one side of the web, making it ideal for coated webs. A vacuum roll is not used to clean a web or to remove moisture from a web.