Powered roller belts are also called MDR belts and Moller® Belts.
They connect a motorized roller to a group of six to ten slave rollers,
called a zone. Usually the motorized roller is in the center of the zone,
but on inclines it is at the top end.
When selecting a belt, choose the one that will move your maximum
box weight (shown below). Note that “Max” loads
exceed our recommendations, but customers have successfully run at
those higher loads using boxes at least 80% as long as the zone.
Also note that four-groove rollers let you double box weights,
e.g., .210" HT Red belts could move 260 lb. boxes.
Various Motor Driven Roller Belts
3/16" (4.8mm) HT Blue Belts
.210" HT RED Belts on
curve with tapered rollers
HEHT Black Belts on 15 roller zone
HEHT Green Belt
on shallow groove
1/4"or 5/16" HT BLUE Belts
on curve with sleeves
Four-groove rollers let
Our Speedy Roller Installer
you double box weights.
makes installation easy.
HT Rough Green Belts
Four groove motor driven rollers are made by
Itoh Denki makes two groove end caps that can provide an additional 2 grooves/roller. Ralphs-Pugh makes 4 groove idlers.
Flat Belts move 120 lbs/roller
Flat & Round Belts move 200 lbs/roller
- Standard 3/16” (4.8mm) belt 83A Color: clear.
For boxes up to 50 lbs (6 lbs/roller). Stretch:14%. NSN# 3030-04-000-7603
Long Life HT (High Tension) Belts
- Long-Life 3/16” (4.8mm) HT BLUE belt 85A Color: “Post
Office Blue”. For boxes up to 80 lbs (9 lbs/roller). Max
100 lbs. New version is 9% stronger, so new max should
be 109 lbs. Stretch: 20%. NSN# 3030-04-000-7603
- Long-Life .210” (5.3mm) HT RED belt 85A Color:
translucent red. For boxes up to 100 lbs (12 lbs/roller). Max
130 lbs. Used on curves in postal distribution centers. See adjacent
picture. Stretch: 20%.
- Long-Life .216” (5.5mm) HEHT BLACK (or red) belt 88A Color:
Black or red. For boxes up to 130 lbs (16 lbs/roller), maximum 180 lbs on 10 roller zones. HEHT belts (Highly Elastic, High Tension)
let you use one size for two different center distances (e.g., 3" and 3.5"). Easily moves
100 lb. boxes on 15 roller zones -- seven slave rollers on each side
of the MDR. (One customer reports using them on 19 roller zones with 9 slaves on each side of the MDR, allowing our HEHT belts to compete with 2-rib poly-v belts at a much lower cost.) When stretched 24% to 30%, they neck down to fit into most 3/16" roller grooves. HEHT belts actually conform to the whole groove, becoming oval in shape, so there is much greater surface contact, which means much greater slip resistance. Lower installation tension makes them relatively easy to install. See adjacent
picture. Stretch: 15% to 30%.
Usually we recommend 24% stretch.
New 3/16" (4.7mm) HEHT 88A translucent green belt is designed for 1.9" rollers with shallow grooves. When stretched 24%, it
will neck down to .165", yet provide more drive than 3/16" 83A belts and 3/16" 85A HT Blue belts.
Our .216" HEHT 88A black belts will move mountains, so our .25" (6.3mm) HEHT 88A black belts should move huge mountains
-- to be determined by our users.
- Long-Life .235” (6mm) HT GREEN belt 85A Color:
translucent green. For boxes up to 120 lbs (15 lbs/roller). Max
160 lbs. Stretch: 20%.
- Long-Life 1/4” (6.4mm) HT BLUE belt 85A Color:
translucent blue. For boxes up to 140 lbs (17 lbs/roller). Max
200 lbs. Used on flexible conveyors and on rollers
that have sleeves. If belts protrude
above the roller surface, sleeves will prevent boxes
from colliding with belts. See adjacent picture. Stretch: 20%.
- Long-Life 5/16” (8mm) HT BLUE belt 85A Color:
translucent blue. For boxes up to 200 lbs (26 lbs/roller).
Max 230 lbs on level surface. Used primarily on rollers
that have sleeves, especially on curves and spiral inclines.
See adjacent picture. Stretch: 20%.
Resistant, HT Rough Green Belts
Jammed boxes will bring slave rollers and belts to a halt. As
soon as a sensor detects a jam, the PLC must turn off its powered
roller quickly -- within 4 seconds. Otherwise, the motor driven roller
will continue to turn under the jammed box, forcing the belts
to slip and overheat. Such abuse will cause premature belt failure.
Smooth belts have a high coefficient of friction (COF), so when
forced to slip, they heat up and abrade or melt. Rough green
belts have a low COF that lets them slip easier with less heat
build up, so they can take more abuse. The trade off is that
they slip too soon, so they cannot move heavy boxes like smooth
belts. We recommend rough green belts in applications where boxes
are light to moderate weight, and where PLC’s are set to
power through jams -- or where there are no sensors to detect jams.
- Abuse Resistant 5mm HT Rough Green belt 88A For
boxes up to 60 lbs (7 lbs/roller max). Stretch 16%.
- Abuse Resistant 6mm HT Rough Green belt 88A For
boxes up to 70 lbs (8 lbs/roller max). These belts will stick
up above regular grooves, causing boxes to skew. They are used
on curves that have tapered sleeves which elevate boxes enough
so they do not touch the belts. Stretch 16%.
Belts or Flat Belts with Guard Sleeves
- 1/4" round belts can move up to 80 lbs per roller if zones
are only three rollers long, i.e., one slave on each side of
a motor driven roller (green end cap). If the rollers do not have
grooves, then 92A flat belt can be used and move up to 120 lbs
per roller. Flat belts may need Guard Sleeves (blue) to prevent
pallets from dislodging the belts. The red Tracking Sleeves prevent
the flat belts from walking.
and Round Belts Combined
- A combination of flat and round belts can move very heavy
loads by creating "pseudo motor driven rollers". Adjacent is a powered
roller zone with 14 rollers that can theoretically move heavy
loads up to 80 lbs per roller -- or 180 lbs per roller if another
set of flat belts is added to the other end of the rollers. If
you specify grooves that are more than 1.25" apart, you can use
wider flat belts that could theoretically move loads up to 400
lbs per roller. For more info Click here.
Lasting Belts: Nine years ago 40,000 of our
3/16 HT BLUE belts were installed in two large postal distribution
centers. Since then, they have been running 24 hrs/day 7 days/week,
and they are still going strong even though some tubs are over
weight and have soft bottoms. Over 1 million are in service
in postal distribution centers throughout the world. Also see "Longer Lasting Belts".
For the best in motor driven roller belts, motorized roller belts, MDR belts, and Moller belts, insist on DuraBelt.