Steel clamped and monobloc idlers with double cylindrical tube or conical tube.They are used in the production of gravity or push curves.
CHOICE OF IDLERS FOR CURVES
Curves with rollers are used to deflect the straight running direction of the package in a circular direction.Their opening angle α° is normally 45°, 90° or 180°.Depending on the flow of material running clockwise or anticlockwise, they are named right or left.In the production of curves with idlers, the following types of rollers can be used:_ individual cylindrical rollers mounted in radially staggered fashion (base-idlers);
- double cylindrical rollers (SERIES 8, pages 54 and 55);
- tapered rollers (SERIES 24, page 56);
- sets of axles with wheels (SERIES 840.02 and 860.02, page 100, catalogue 5.1), in specific cases.
In the design phase, the curve with cylindrical rollers must be proportionate with greater slope and with the radius of internal curvature Ri [mm] greater than that for the curve with tapered rollers:
- curve with cylindrical rollers Ri ≥ 1.75 T [mm] cylindrical roller;
- curve with tapered rollers Ri ≤ 1.50 T [mm] tapered roller.
These parameters are valid with the table length T [mm] of both types of rollers remaining equal.A greater degree of reliability of transport is obtained by using tapered rollers because the package maintains both the correct running trajectory and the regularity of flow even without the aid of containment side panels or other safety devices.The packages are pushed if the transport plane is horizontal; they are triggered by the force of gravity if they are inclined at the right gradient.The theoretical determination of gradient λ [°] or [%] is performed as in the “Choice of idlers” section (from page 8 to 11).
As with rectilinear conveyors, packages with a smooth and rigid supporting surface require at least x=3 support rollers during running; with an uneven and elastic surface a greater number of rollers.The wheelbase l [mm] of rollers for curves is calculated on the average running range of package RM [mm].The technical characteristics of SERIES 24 tapered idlers are those of clamped cylindrical rollers having the same axle diameters and tube diameter as the smaller diameters of tapered rollers.For roller code designation, see page 50.