It is sometimes necessary to mount rolls on vertical axes, between driven roll stages, to exert side pressure to a shape when it is needed for forming or guiding.
Likewise, when cut-to-length strips are fed through a roll forming machine, interstage guiding devices are used to guide the lead end in its progression from roll to roll.
These items, together with straightening guides or rolls, are considered accessory tooling and are mounted on standard fixtures available from all manufacturers for the purpose of guiding.
Shape orientation, or its position relative to the roll axis, must be considered as an important element of roll design. It can affect machine cost, tool cost, part quality and also the overall efficiency of the operation. A particular orientation may be preferred over another because of:
- The limitations of the forming machine based on the number of roll stages and roll diameter.
- The limitations of the cutoff machine based on the die space and stroke.
- A need for the finished or exposed surface of the section to be visible to the operator as it is being formed.
- A need to position the cutoff burr in a particular direction.
- A need to tool similar sections in “combination” or “sectioned” rolls.
- A need to minimize, control or eliminate:
- Scratching and galling
- Blind bends
- Trapped coolant
- The requirement of other in-line operations, e.g., coiling, prepunching, postpunching.
- Tool cost economies or ease of setup and operation.
- The need to position a laminated section most conveniently for the application of the core of cover strips involved.