UNI-LOAD® CHUTE
To meet the need for instantaneous
shutoff on high accuracy loading, PEBCO® designed the patented
Uni-Load® Chute. The Uni-Load® Chute is used on truck and
rail loadout systems. This chute has these advantages:
- Reduces amount of material
in-transit time after gate shutoff
- Deploys chute quickly
- Improves even product
distribution
- Provides collision protection of
chute
- Optimum loading of the car since
the chute can be positioned both laterally, as well as
vertically.
- Instantaneous shut-off of the
gate is most important to eliminate the free fall of material. This will
help assist in optimum loading of the train.
- Reduced dusting at connection
point of the Uni-Load® to the chute.
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Uni-Load®
Chute | PEBCO® gates and blade
actuating components are sized to reliably open and close under material flow
conditions and theoretical full head loads. They are also sized to close through
a standing column of material. However, the gate and actuator may not provide
adequate force to physically shear the material.
The net result is the gate blade movement
in the "close" direction will always be adequate to terminate material flow; but
may not be adequate to shear the product should it become trapped between the
leading edge of the blade and the inlet throat or the gate frame.
PNEUMATIC AIR RECEIVER FOR "FAILSAFE" OPERATION
An air receiver tank with the necessary
check valve, relief valve, shut off valve, tank bleed valve and a pressure
gauge, 0-200 psi dial. The air receiver tank will allow the gate to close in
case of an emergency. Receiver tank to be installed near the gate.
The receiver tank will be charged
by the system's normal operating pressure. It is suggested by means of the
electric control system, the P.C. logic should be programmed to "fail safe" when
either there is a system power loss or low system air pressure as detected by
system air pressure switch.
LOAD CONTROL SYSTEMS
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Our world, the world of moving and
loading bulk materials, is in a state of accelerating technology, thanks
in major part to PEBCO® research and development. In the
1980's, our engineers and management foresaw that the colliding pressures
of regulations vs. economics were going to force a new loading technology
to emerge from the bulk materials loading and handling industry. At that
time PEBCO® began to design the bulk loading systems of
the future. Those loading systems are now, in the 1990's at work all over
the world, loading with amazing speed and weight accuracies, in totally
automated environments. PEBCO® has led the growth cycle
that produced these loading and weighing advances, and is one of the few
companies in the world that moves with complete authority in the area of
bulk loading sciences.
The new load technology addresses,
and solves, the persistent problem of bulk loading - how to load at great
speed, while measuring the weight and symmetry of the load very
accurately. This accuracy of weight is paramount in today's environment,
as transportation regulators put strict caps on weight per car size, and
shippers demand no less than the maximum weight allowed per car.
Coupled-in-Motion Weighing and Batch Weighing are two loading techniques
that have been designed to reconcile these needs.
Coupled-in-Motion Weighing is
an apt description of this weigh system. The cars of a unit train may be
weighed and measured by track scales and scanners while coupled together
and moving. A sophisticated computer calculates the optimum load weight
for each car, and controls material delivery to the cars by actuating the
chute above them as they move through the loading area.
Output signals from
detection equipment allow the computer to control the flood chute above
the moving cars. |
With the train above moving
left to right, the front end of the car to be loaded is just under the
chute. The position is detected and the chute automatically swings down
into position, ready for loading. As soon as the chute is lowered, the
gate is automatically opened and flood loading of the car begins. At this
time, no weights are being taken. The car proceeds across the scale, and
the first truck of car #3 has moved onto Scale 2. The chute is
approximately in the center of car #2. Scales 2 and 3 are being used to
determine the gross weight of the car and to compare that weight with the
pre-set individual car "target" weight to control the cut-off point. In
addition to car #2 being on Scales 2 and 3, the front truck of car #3 and
the rear truck of car #1 are also scaleborne. The computer automatically
calculates the actual weight of car #2 as follows: the weight of the rear
truck of car #1 is subtracted from the weight recorded by Scale 3.
Similarly, the front truck of car #3 is subtracted from the weight
recorded by Scale 2. The two remainders are added to give the actual
weight of car #2.
A PEBCO® coupled-in-motion system serves this
large coal mine with 8000 TPH capacity.
Operators monitor loading as computers gather data
to deliver pinpoint loads. |
Flood gates automatically close as the target
weight is
reached. | |
 Coupled-in-Motion Weighing, as sophisticated as it is, would not be
wholly effective unless it were used with a mechanical loading system that could
activate as rapidly as the computers demanded. The old, slow traversing chute
systems simply could not keep up, and would handicap the system's speed
severely. PEBCO® engineers overcame this problem with their introduction of the
Uni-Load® system. It is a mechanical loading system that features a
unique, hinging and pivoting chute that has enabled operators to load coal unit
trains in just over half an hour, and loads as many as 11 unit trains in a
24-hour period.
The Unique features of the
Uni-Load® system are as follows:
The Chute - Rather than traverse
horizontally from a side ("clear") position to a "load" position over the car,
the Uni-Load® system chute is fixed in position directly over the
car. When loading is required, the chute quickly swings downward on its hinged
pivot.
The Gate - The non-jamming gate
that regulates coal flow has been moved from a position at the top of the chute
to the bottom of the chute.
These two changes, to the chute and the
gate, radically alter traditional loadout expectations and improve the system in
these important categories:
Speed - The Uni-Load® chute swings from "clear" to "load" in about five seconds, much faster than
conventional designs. The regulating gate can be actuated in two seconds, giving
the loadout operator virtually unlimited control of the load. With this control
comes operator confidence and faster loading times.
Uniformity of Load - the
positioning of the gate at the bottom of the chute eliminates the problem of
"in-transit" coal, i.e. coal traveling down the chute after the load is shut off
at the top.
Maintenance - The simple design of
the Uni-Load® arrangement requires fewer moving parts than
traditional designs and substantially less structural steel. The design of the
pivot chute provides protection against accidental contact with locomotives or
moving cars.
Dusting - Because the material is
dropped only the short distance from the gate at the bottom of the chute into
the car, dusting is dramatically reduced and, in some cases, eliminated.
Safety - The precise flow
available with the Uni-Load® system allows a safer operation. Even
should an accident occur, the chute can be raised and the flow of material can
be cut off.
At the operator's command, this gate
activates from fully closed to fully open in seconds, giving pinpoint
control to the operator. |
Because the material is dropped only
a short distance from the gate at the chute bottom to the car, dusting is
dramatically reduced. |
| Uni-Load®
plays a significant role in the effectiveness of the other advanced
loading technique, Batch Weighing.
A batch weigh system utilizes a
weigh bin to measure precisely a pre-determined amount of material to be
loaded into truck or rail cars. The target weight is determined by means
of computer calculations prior to load. Batch weigh systems are capable of
static weight accuracies of 0.1% at a load rate of 7000 TPH.
Dynamic load control accuracies
have been improved significantly by using the Uni-Load® with
the flow control gate at the bottom of the chute and a loss-in-weight or
weigh down mode for the electronics. The load control accuracy with the
Uni-Load® has been documented at plus or minus 500 pounds for
90% of the rail cars loaded.
A typical batch weigh sequence
would work as follows:
To initiate a load, the surge bin gates open to
fill the weigh bin above the load chute. A precisely-measured batch of 100
tons, for example, would fill in about 10 seconds. When the fill is
complete, a "ready" light is illuminated on the operator's control panel.
with the rail car and the load chute in position, the weigh bin
discharges, and continues as the car passes through the load area. When
the weigh bin is empty, the computer closes the discharge gate. The
computer automatically subtracts the car's empty weight from full weight,
and records this net weight of delivered material in its memory. The surge
gates automatically refill when the computation is recorded. This sequence
continues until the computer recognizes the last car, at which time the
re-filling procedure is stopped, and the batcher prints out the grand
total in pounds. |
(Above) A PEBCO®
batch weigh system loading coal at 4000 TPH at an eastern US
mine. (Below) Controls for a sophisticated blending system, combining raw
coal and clean coal to PEBCO®
loadout. (Below, Inset) Interior of a control panel for a large western
coal mine. Panels such as this can automatically control sampling systems,
conveyors, belt scales, batch loading, blending and dust
collection.
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| American industry's move to automated systems has now reached the
bulk material handling field. The breakthrough facility was one designed
by PEBCO® for the power generation plant in the city of
Springfield, Illinois. This system weighs incoming coal trucks,
batch-loads coal into those trucks and transmits the loading data both to
the mine's central accounting computer for billing, and to the end user.
In this loading sequence, the truck driver never leaves his cap, and it is
accomplished without the need for an operator in the control
room. |
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| 1. The
truck enters a pitless truck scale; the driver inserts a plastic card into
the card reader. The card records the driver's name, tractor size, load
information and other specifics. |
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2. When
this information is verified by the computer, the driver receives a green
light and proceeds to the loading station under the 80'-tall loadout
structure. |
3. The batch is automatically determined by the
information on the driver's card and his weight on the scale. The
UNI-LOAD® chute moves from a "clear" position ... |
4. ...to a "load" position when the batch is ready to be
delivered. More verification of truck position and trailer configuration
is being done by photo-electric cells. |
5. When loading is complete, the driver receives a
flashing green light. As he proceeds, the ticket printer gives him a
record of the load just completed, and his cumulative daily
total. |
This product is covered by one or more of the
following US patents: #4,372,273, 4,659,274 and foreign patents. |
