Live shaft rollers are rolls mounted in external bearings where the roll shafts (or journals) rotate with the roll. Because they can be mount in self-aligning bearings, live shaft rolls are capable of handling higher loads than comparable dead shaft idlers. Live Shaft Idler Rolls are generally used where the web or the environment challenges like high heat ovens or harsh chemicals can impact roll integrity or performance.
Dead Shaft Idler Rolls are rollers with internal bearings, designed to rotate around a stationary, dead shaft. Since only the roll shell is rotating, the dead shaft roll has a lower rotating inertia and with low friction bearings installed, dead shaft idlers are generally the best solution when a free turning roll is needed. Webex Dead Shaft Idlers have set the industry standard for over 25 years.
Each roll is designed for the optimum balance between heat transfer, minimal pressure drop inside the roll, correct fluid velocity and minimum temperature rise across the roll face. In fact, our design process is so exact, we guarantee temperatures to within ±1°F across the face of the roll.
Webex heat transfer rolls are available in a wide variety of materials such as carbon steel, aluminum, stainless steel and alloy steel. We offer several coating and plating options to customize your roll to fit your exact application. In addition, we can provide you with ASME-certified pressure vessels from our PFE brand.
Webex often produces heat transfer rolls with ultra-tight tolerances of less than 100 millionths total indicator run out. Mirror finishing with optically-perfect, polished chrome plating is also available.
Using a sophisticated analysis program, Webex Engineers can determine:
The Webex ZDR - Anti-Deflection Roll - is a specially designed roll engineered to reduce or virtually eliminate roll deflection caused by external forces. Precision engineering and high-grade materials make the ZDR aperfect solution for film casting and calendering operations.
The counteract a wide range of external forces, the ZDR roll uses a large, solid shaft constructed of high-grade alloy steel. The shaft is machined and profiled for a precision pressure fit with an external steel roller. Unlike typical roll designs, the ZDR shaft supports the precision steel roller at the center, not at the roller ends. The exact location and extent of contact for this direct shaft-to-roll support are calculated by Webex engineers based upon the parameters of your application.
Webex’s rugged bowed rolls provide effective web handling for the most demanding web converters — available in both permanent bow and adjustable bow models. Proven mounting solutions ensure ease of installation as well as extended versatility in web control. These precision bowed rolls are ideal for separation of slit webs, or the elimination of web wrinkles, slack edges and soft spots. Exceptional performance is evidenced in the even distribution of lateral web tension and vibration-free operation at all specified speeds.
Also referred to as a concave roll, reverse crown or bow tie roll, the reverse taper roll has a larger diameter at the outer edges and a smaller diameter at the roll centerline. The roll, as a result of its profile, creates a surface speed differential at each different roll diameter. The resulting tension differential, or higher edge stress, ultimately results in the material climbing outward toward the larger diameter edges of the roll.
To be effective the web and the roll must be in a state of traction and therefore, web tension and wrap angle are very important components to the effectiveness of reverse taper rolls. The amount of taper or crown depends on the application but generally is .0005" to .001" per inch, diametrical taper from the roll centerline to the edge. Reverse taper rolls are definitely the most cost effective web spreading devices. They have an advantage in that, even if they do not achieve the desired action, they can still be effectively applied anywhere in the line as general idler rollers.
These anti-wrinkle rolls can influence your web in various ways, including stretching it, spreading it or allowing the web to lay flat and simply not induce wrinkles in the first place.
These idlers are covered with a rubber elastomer and are precision machined with angled, outward spiraling grooves across the roll surface. There are different elastomers available for use, each with different physical properties such as solvent resistance, heat resistance and hardness. In addition, various groove patterns are available to meet your specific application needs. Our Customer Support Specialists can help you determine which elastomer and groove pattern is best for your specific application.
Grooved metal rolls are also often applied as wrinkle removal devices. Because there is no scientific reason that these should be effective, Webex engineers do not actively recommend the use of grooved metal rollers. However, we have many users in real-world applications that swear by the effectiveness of grooved metal rolls as wrinkle removal devices.
Webex Vacuum Rolls pull the web into intimate contact with the roll, increasing friction forces that help prevent web slippage. The result is a highly effective web control device that can handle much lower tensions and much higher tension differentials.
Vacuum Roll Options:
Repairing or refurbishing your rolls can help you enhance your web process without making capital investments in new machinery.
Properly refurbished rolls offer great results:
Get replacement carbon fiber bridge mandrel adaptors for hydraulic sleeve-style flexo presses without enduring the long lead times and premium pricing common with offshore press OEMs.
Webex uses the same in-house carbon fiber winding technology that produces our highly respected Idler Rolls to make mandrel adaptors for flexo presses. Our engineering team will help duplicate the exact specifications of your original mandrel adaptors to manufacturer a high quality adapter that meets the exacting demands of today’s high speed flexographic presses.
Interested in a free on-site evaluation? Make sure to let us know when you fill out the 'Request Info' form below.
Lightweight, precision balanced carbon fiber flexographic print cylinders decrease bounce between the print cylinder and impression drum so presses can run at higher critical speeds. As an alternative to steel or other metal print cylinders, lightweight carbon fiber cylinders also offer better ergonomics for an injury-free workplace.
With our in-house composite carbon fiber winding operations, each print cylinder is engineered specifically to your application. By varying the fiber types, resins and winding techniques, we can control your cylinder tube strength and stiffness – creating a cylinder designed to deliver excellent performance.
The demands placed on any roller can be quite different from system to system - even roll to roll. That's why we custom design all kinds of rollers to meet the demands of unique web handling and converting processes.
Our skilled technicians will manufacture your roll in-house with strict attention to detail. The entire process of machining, grinding, balancing and finishing is done at Webex. From cradle to crate, we do it all.
Perhaps your web is abrasive enough to scratch the surface of steel idlers. Or maybe the caustic vapors of your coating operation likes to pit and corrode aluminum rolls. And it wouldn't be unusual if your coated web was causing some trouble by sticking just a little too much to certain rolls in the line.
These are typical challenges where custom roll coatings and platings are used successfully every day to improve web handling. The real challenges, however, are much more numerous. Likewise, the custom solutions Webex has to offer are quite varied and unique.
We present here an overview of the more common coating and plating options used today. For professional assistance in selecting the best possible option, talk to our Customer Support Specialists. They have the experience and expertise to properly shape your decision.
Common Options Include:
These heavy duty flaking rolls are designed specifically to withstand high pressures and related heat when rolling or crushing corn, bran and rice into cereal flakes, bio fuel mass, feed stock and assorted other engineered food forms.
Manufactured with thicker, hardened alloy steel outer shells with a heavy-duty internal mandrel and journals, these custom-manufactured chill rolls offer an extended production life without shell cracking, weld cracking, or leaky ends.
Instead of welded ends, roll journals and the internal mandrel are shrink-fitted into the outer shells with precise tolerances. A mechanical seal is also added on the roll ends for extra security. Internal water passages are precision-engineered to properly control increased temperatures resulting from the high-pressure nip process. Outer roll surfaces are ground to within .0002" TIR to assure better nip tolerances and more consistent flakes.