Flexible Shaft Backing Assemblies (FSBA) & Segmented Idler Roll (SIR)
Segmented Backing Assemblies have the capability of a far greater range of shape adjustment than conventional solid shaft backing assemblies. The design of the segmented Backing Assembly allows for a far greater degree of offset between adjacent saddles. Thus, as Figure 1 shows, we can dial in a 4th order quarter buckle type control shape and further more, can move that shape closer to the center or farther out to the edge of the strip! This new development allows for far greater 1/4 buckle control and 4th order shape characteristics. With this new development, we can set up a Sendzimir mill for the "M" or "W" shapes necessary for better shape control. In addition, we can set a variable wave amplitude and period of the mill. Of course, the segmented design allows for a combination of wedge offset, 2nd order and 4th order shape control.
Standard design implementation includes modified "B" and "C" backing assemblies as well as a modified Upper Idler roll.
This design has proven to be a significant improvement to new and existing mills. The results of this several year long research effort has been to retain the rigid "die-like" capability of the Zero-crown monoblock housing while at the same time allow for a much greater degree of shape control internal to the mill using the latest technological advances in machining techniques.
We have supplied these segmented Backing Assemblies into Europe, Asia and Japan. This type of shape control is unparalleled for the small work roll mill industry! In fact, no other supplier of cluster mills outside of the T. Sendzimir, Inc family can supply this degree of shape control capability.
Classic Backing Assembly shafts are solid and therefore will not bend in any complex shape other than the simple parabola.
In Figure 2, we show the maximum and minimum extents of this parabolic shape adjustment. This effect is also known as 2nd order shape control.
Segmented Backing Assemblies are designed to be torsionally rigid but yet can bend dramatically at each saddle position.
Thus, the mill crown control can be set up for 4th order (1/4 buckle) shape control required for today's strict shape requirements as shown by the example wave forms to the left. This wave form shape is infinitely adjustable for wave amplitude and phase position.