| Roller turns are the most
economical device, from the standpoint of first cost for providing
radial support to overhead conveyor chain around a horizontal turn.
Although they lack many advantages of traction wheels turns, they can
perform a satisfactory job in most conveyor installations. Because of
lower first cost, they are widely used. Anchor roller turns are
constructed with a separate mounting frame from which roller segments,
segment support brackets and rail are supported. This sound construction
method simplifies installation in addition to providing a rigid, well
braced turn. The separate mounting frame enables the turn to withstand
chain pulls far in excess of any that might be encountered in service.
This unusual strength achieved produces an inherent safety factor not
found in systems where the rail itself provides the backbone for the
turn.
Anchor roller turns can be built to any required radius (12" or
greater) and any degree of arc up to 180°.
Standard radii, which should be used whenever possible for economy
reason, are 18", 24", 30", 36", 48" and 60". Standard turn arc are 30°,
45°, 60°, 90°, and 180°. Larger radii and other turn arcs are available
on special order. |
When transporting large
objects , which require support from two separate conveyor trolley
assemblies, it is sometimes necessary to specify a large radius turn,
such as a 14' radius. In such a case, it is usually more economical to
break the turn into a series of smaller increments, such as several 18"
radius turns at 15° arc, in sufficient
number to accomplish the total desired turn.
Anchor roller
turns are generally furnished with lubrication fittings in the roller
pin. They also can be provided with lubrication-for-life rollers or with
other special bearings if required.
On the overhead conveyor layout drawing, a length of straight rail
equal to one trolley spacing should always be allowed between tangent
points adjoining horizontal turns and vertical curves
In determining the proper size turn to employ, care must be taken to
insure no interference between adjacent loads as they negotiate the
turn. |
