Roll Manufacturing And Repair

Roll manufacturing spans a broad range of industries and processes. Steel mill rolls, printing rolls and textile rolls are three of the most common. Rolls can vary in size from one pound to as much as 400,000 pounds. Parts weighing 2,000 to 25,000 pounds are the most common. Refurbishing a roll may be as easy as applying a urethane or plastic spray coating or as difficult as rebuilding the entire roll with a plasma spray coating. Some rolls are simply re-ground to bring the roll back into tolerance, while others must be ground prior to applying a new coating. Finish operations may involve turning or grinding between centers to bring the roll to size depending on accuracy requirements.

Rolls can be held between centers or the bearing journals can be supported on steady rests while the roll is turned or ground. Often, both the roll surface and the bearing journals require repair. Center holes can also be damaged or out of concentricity with the journals due to previous repairs. These types of issues coupled with the massive weight of the rolls present many challenges when rebuilding rolls.

Large Part Capacities

Riten Extra Heavy Duty live centers and Super Duty live centers are manufactured specifically for applications where excessive weights and tight tolerances are the requirement. Depending on the taper, Extra Heavy Duty live centers can support part weights in excess of 22,000 pounds, while Super Duty live centers have work piece weight capabilities in excess of 65,000 pounds. Riten also has the capability to design and build special live centers and special dead centers with part weight capacities approaching 100,000 pounds. All Riten Super duty live centers pass a rigorous inspection procedure through out the manufacturing process. Documentation includes material certification, heat treat certification and magnetic particle inspection certification.

Live Chuck Mandrels

Run out and taper are common issues associated with misalignment between center holes and bearing journals. Riten live chuck mandrels provide an excellent solution when the center holes or the journals of the roll are not on axis. The Riten live chuck mandrel provides the operator with the ability to adjust position, removing taper in the roll by adjusting the chuck. This eliminates turning the roll around or re-working center holes. Riten live chuck mandrels are available in both standard Morse Tapers and custom taper configurations with 3-jaw and 4-jaw chucks. Consult a product specialist to configure a live chuck mandrel to fit your application.

Thermal Expansion

Thermal expansion is a common occurrence when rebuilding rolls. The build up of heat in the roll as it is pre-heated or coated presents a unique set of problems during turning or grinding. As the temperature increases, the roll expands axially creating massive pressure on both the tailstock/headstock bearings or the live center bearings. Riten spring loaded live centers and linear compensating live centers are engineered for just such an application. The springs and/or washers in the live center provide linear compensation, allowing the part to expand and contract while maintaining an ample amount of pressure on the workpiece.

Versatility

Our standard face drivers feature the capability to turn a large range of part diameters, from small transmission shafts to very large shafts used in pulverizing machinery. At one large Midwest gear manufacturer our standard 48FM face driver holds a family of shafts during both the roughing and finish turning operations. Major work piece diameters range from under three inches to over fourteen inches in diameter. Riten face drivers are often used in conjunction with CNC Heavy Duty live centers. Depending on the taper, Heavy Duty live centers can support part weights in excess of twenty thousand pounds, while Super Duty live centers can support part weights in excess of sixty thousand pounds.

Reliability

As the preferred supplier to the Rubber Roller Group, Riten Industries provides tools to meet their critical workholding requirements. Our live centers, dead centers and face drivers are designed and manufactured to perform at the highest level. We are ISO 9001:2008 certified and demand the highest quality materials from our suppliers to use in the manufacture of our products. All Riten standard and special live centers, dead centers and face drivers are manufactured to tight tolerances and thoroughly inspected and tested before being shipped to our customers.

Experience

Only Riten Industries, Inc. can provide the experience necessary to design and manufacture the technology for these demanding applications. Riten Industries, a trusted manufacturer for over seventy years, providing live centers, dead centers, and face drivers to meet the demanding requirements of roll manufacturers.

Riten Industries, Solutions, Not Excuses…