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2
Belt Conveyors
Conveyor Width
The conveyor width is the width of the conveyor
frame without the tails. The belt is narrower to allow
for self-adjusting tracking, between 10 and 50 mm
depending on the system.
Conveyor Length
The conveyor length is a nominal dimension and
is defined as the outer distance of the head parts
when the system is not tensioned. The actual
conveyor length differs and is calculated based on
the following nominal dimension (at an ambient
temperature of approximately 20°):
+ 1 - 3.5 mm per side
(rollers protruding over head parts)
± 1 - 5 mm per side (belt thickness tolerance)
± 0.8% of the conveyor length (belt length tolerance)
+ 0.3% of the conveyor length (belt tension distance)
A precisely defined installation length can be
implemented upon request, primarily with lower
belt drives.
Length-Width Ratio
To ensure secure and stable tracking, belt conveyors
with length-to-width ratios of 1:1 to 50:1 can be
provided.
Length to width of 1:1 to 1.5:1
Stable area with restrictions and with additional
design measures, e.g. lengthwise fence.
Length to width of 1.5:1 to 2:1
Stable area, without restrictions in most cases,
but with a need for a design test.
Length to width of 2:1 to 20:1
Stable area without restrictions.
Length to width of 20:1 to 50:1
Stable area only with laterally stiff belts and without
the presence of lateral forces. Lateral forces occur,
for example, when there is lateral movement, lateral
product discharge, lateral product transfer, lateral
product alignment using a side rail and asymmetric
load distribution.
Speed
The maximum conveying speed depends on the
motor selected, the load capacity, the operating
mode and other factors.
With an indirect chain drive with a ø 53 mm roller, a
speed of up to 80 m/min is possible. The selection
of a timing belt for force transmission is recommended
for 30 m/min or higher, and is standard
for 60 m/min or higher and cycling operation. Slim
rollers are balanced for speeds of 60 m/min or
higher, and dynamically balanced for 100 m/min or
higher.
For high speeds, it is sensible to choose large driving
rolls (e.g. for 80 m/min with the GUF-P 2000, a BC
drive with a ø 88 mm roller).
Adjustment Ranges
The mk reglomat lets you control the conveyor speed
within a range of 1:7 (10-70 Hz), assuming an alternating
current and the nominal speed at 50 Hz. For
internal drives (drum motors), the adjustment range
is 1:3 (20-60 Hz). With direct current, the range is
1:6 (0.25-1.5 A or 0.5-3 A) see page 314.