Conveyor Belt

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Navigation: Main Page -> Models -> Material Handling Models


General Description

The Conveyor Belt model is used to transfer material from one point to another in a Dynamic project. The Conveyor Belt can have multiple feed points and multiple product points.

This unit operation is used extensively in Solids material handling projects.

The Conveyor Belt can be configured to operate in any one of a number of different ways. These will be described below:

Standard Conveyor Belt

A conventional Conveyor Belt which may have multiple feed points and either a single fixed discharge point or multiple fixed discharge points. A conveyor with stationary trippers is included here.

Apron or Belt Feeder

The Conveyor Belt model may be configured to act as an Apron or Belt Feeder, in which required feed flow is based on the speed of the belt.

To configure a Conveyor Belt as an Apron Feeder or Belt Feeder, it must be located downstream of a surge unit in the flowsheet - such as a Tank or Multistore.

Select the BeltFeeder tick box on the ConveyorBelt Tab and specify the Fd.FullSpeedCapacity as shown below:

BeltFeeder137.png

This will restrict the feed to one fixed feed (at start of belt) and the product to one fixed product (at end of belt).

As the speed of the belt changes, the amount of material withdrawn from the upstream bin will change, up to the maximum defined by the user. The Conveyor Belt will set the required capacity in the link between the conveyor and the upstream bin.

Movable Tripper or Shuttle Conveyor

  1. A Shuttle conveyor with 2 or more products. The user may set the speed of the shuttle drive.
  2. A Tripper conveyor, with a tripper drive.


NOTE: All connections to and from the conveyor belt will operate in the transfer mode.

Diagram

Conveyor.jpg

The diagram shows the default drawing of the Conveyor, with streams that may be connected to the unit. All of the connections are optional, i.e. the user does not have to connect any streams to either the Feed or the Product connections.

The user may have only a single Feed and a single Product connection, or any number of each.

The contents of the conveyor belt are only saved and recovered if the option "Save Object Files (extra state.result info)" in the save project dialog is selected. If this is not selected, the conveyor belt is empty at project load.

Inputs and Outputs

Label Required
Optional
Input
Output
Number of Connections Description
Min Max.
Feed Optional In 0 20* The Feed to the Conveyor
Product Optional Out 0 20* The Product from the Conveyor
  • If the Belt Feeder option is chosen, the the number of feeds will be restricted to one and the number of products will be restricted to one.

Model Theory

Power Draw - CEMA Method

This method is based on a graphical method described in the following reference:

"Belt Conveyors for Bulk Materials", Second Edition, 1979, Conveyor Equipment Manufacturers Association.

Regression analysis has been performed on the graphs provided in the reference to determine constants required to turn this into mathematical formulas.

There are three user specified values required for this method, the empty belt density, the belt width and the belt elevation.

The following steps are the followed to calculate the power requirements of the belt:

  1. Calculate the loading of the empty belt from the empty belt density and the belt width.
  2. Calculate the power required to drive the empty belt from the empty loading (step 1) and the belt speed.
  3. Calculate the power required to elevate the material from the belt elevation and average flow of material on the belt.
  4. Calculate the power required to convey the material from the conveyor length and average flow of material on the belt.
  5. Calculate the total (ideal) power by adding the calculated power requirements of the previous three steps together.

Data Sections

Summary of Data Sections

The default sections and variable names are described in detail in the following tables. The default Conveyor Belt access window consists of four sections. This number may increase or decrease, based on user configuration.

  1. ConveyorBelt - This tab page contains general configuration information.
  2. BeltDrive - This tab page is used to configure the operation of the conveyor belt drive.
  3. Feeds - This is where the user can define the feed inlet position(s).
  4. Products - This is where the user can define the product outlet position(s).
  5. FeedDrives - Optional tab, only visible if NFeedDrives > 0. The number of tab pages available will match the number of NFeedDrives specified by the user. These tab pages are used to configure the Feed Drives.
  6. ProdDrives - Optional tab, only visible if NProdDrives > 0. The number of tab pages available will match the number of NProdDrives specified by the user. These tab pages are used to configure the Product Drives.
  7. WtMtrs - This page is used to configure the weightometers. This page will only appear if NWeightometers (the number of weightometers specified on the first tab page) > 0.
  8. Loading - This page is used to display the belt loading profile. This page will only appear if the ShowLoading option is ticked.
  9. Info tab - Contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.
  10. Links - This tab page contains a summary table for all the input and output streams.
  11. Audit tab - contains summary information required for Mass and Energy balance. See Model Examples for enthalpy calculation Examples.


These sections are visible if the user checks the relevant box on the first page.

Conveyor Belt Page

Unit Type: ConveyorBelt - The first tab page in the access window will have this name.

Tag / Symbol Input / Calc Description/Calculated Variables / Options
Common Data on First Tab Page
Requirements
BeltFeeder Tick Box The conveyor is auto-configured as a belt feeder (or Apron Feeder). Feed and product positions are fixed at the start and ends of the conveyor, respectively. User will be able to set a limit on the feeder capacity. This is only available in SysCAD 9.2 Build 135 or later.
Length Input The total length of the conveyor. Note: This includes any shuttle or tripper attached to the conveyor.
MaxSpeed Input The maximum speed of the conveyor.
FullLoad Input The loading, in mass per length, that the conveyor is designed handle at the maximum power draw.
MaxSpillLoad Input The maximum loading, in mass per length, that the conveyor can handle before spillage occurs.
MaxStallLoad Input The maximum load the conveyor can handle before it stalls.
UsePowerSupply Tick Box Only available in Build 136 or earlier. If this is enabled, then if the power supply for the project is turned off, then the conveyor will stop. The data fields relating to the Power supply will be visible on all the conveyor drive tabs.
Results
WasRunning Display If the conveyor was running in the previous step, then this will have a value of 1, otherwise it will be 0.
BeltStopped Tickbox This will be True if the conveyor is stopped, otherwise False.
BeltSpeed Calc The current conveyor speed - BeltSpeed = MaxSpeed * Actual Speed Fraction.
AvgLoading Calc The average loading, in Mass per length, of the conveyor.
AvgFullLoadFrac Calc This value = Average Loading/Full Load. This is also used to calculate the power draw of the conveyor. This field is only displayed if 'ShowFullLoadFrac' under Options is ticked.
TotalMass Calc The total mass on the conveyor.
InitTtlMass Calc The initial total mass on the conveyor.
DeltaTtlMass Calc The difference between the current mass on the conveyor (TotalMass) and the inital mass on the conveyor (InitTtlMass).
TotalSpilt Input / Calc The total material spilt from the belt.
NOTE: This is a read/write field. As spillage occurs, the cumulative amount will be displayed here. However, the user can also enter 0 to reset the spillage count.
TotalVented Input / Calc The total mass of gases vented.
NOTE: This is a read/write field. As venting occurs, the cumulative amount will be displayed here. However, the user can also enter 0 to reset the venting count.
Feed Options
FeedConnections Fixed All Feed points onto the conveyor are fixed and therefore there are no Feed Drives. This option is forced if the Belt Feeder Option is chosen.
Fixed or Moving The user may have a combination of Fixed and Moving feed points to the conveyor. In this case the user may select 0 or 1 or more Feed Drives.
Moving All feed points to the conveyor are moving. In this case the user must select at least 1 Feed Drive.
NFeedDrives Input The number of feed drives. The FeedDrives tab page(s) will then be visible. This field is NOT visible if the user selects 'FeedConnections' = Fixed.
(the following fields are only visible if the BeltFeeder Option is selected)
Fd.StreamTag Display The tag of the feed stream.
Fd.Type Display The type of the feed stream connection.
Fd.Pos Display The position of the feed stream from the start of the conveyor.
Fd.Limited Display The feed flow rate is limited.
Fd.FullSpeedCapacity Input This is the maximum capacity that can be fed onto the conveyor. This number will be passed back to the feed stream, thus limiting the flow from a tank or other surge unit to this capacity.
Fd.Qm Display The mass flow rate of the feed stream.
Product Options
ProdConnections Fixed All product points from the conveyor are fixed and therefore there are no Prod Drives. This option is forced if the Belt Feeder Option is chosen.
Fixed or Moving The user may have a combination of Fixed and Moving product points from the conveyor. In this case the user may select 0 or 1 or more Prod Drives.
Moving All product points to the conveyor are moving. In this case the user must select at least 1 Prod Drive.
Moving (over Bins) All product points to the conveyor are moving over bins. Each product from the conveyor will discharge to a bin with a user defined start distance and width. In this case there will be 1 Prod Drive.
NProdDrives Input The number of product drives. The ProdDrives tab page(s) will then be visible.
Note: If the 'Moving over Bins' option has been selected, then this field will be read only and display the value of 1. This field is NOT visible if the user selects 'ProdConnections' = Fixed.
(the following fields are only visible if the BeltFeeder Option is selected)
Pr.StreamTag Display The tag of the product stream.
Pr.Type Display The type of the product stream connection.
Pr.Pos Display The position of the product stream from the start of the conveyor.
Pr.Removal Display The proportion of material on the conveyor that will be sent to this product stream.
Pr.Qm Display The mass flow rate of the product stream.
Options
ShowFullLoadFrac Tickbox If this is enabled then the fractional average of the full load will be displayed.
ShowLoading Tickbox This displays the mass loading along the conveyor length on the Loading tab page.
NWeightometers Input Number of weightometers. If this is > 0, a new Tab page WtMtrs will be added in the access Window.
Preset None The Preset action will have no effect on the speed or movement of the conveyor.
Off The Preset action will turn the conveyor off.
Forward The Preset action will cause the conveyor to run in the forward direction at speed = 100%.
Reverse The Preset action will cause the conveyor to run in the reverse direction at speed = -100%.
PresetClear None The Preset action will have no effect on the material on the conveyor.
End The Preset action will empty the material between the set take-off point and the end of the conveyor.
All The Preset action will remove all of the material from the conveyor, i.e. it will empty the conveyor.
Tolerances and Configuration for managing queue sections of material
PrevTotalMass Display 'TotalMass' on the previous step.
PrevSpillMass Display 'TotalSplit' on the previous step.
PrevVentMass Display 'TotalVented' the previous step.
Balance Display
MinLoading Input The minimum loading of a section of the conveyor.
NSections Display The number of sections into which the Conveyor Belt is divided. For internal recording purposes only.
NSteps Display The number of internal steps required by the conveyor model.
MinSect...
Length Input The minimum length of each section as a % of total length.
LoadTol Input The load tolerance for determing if adjacent sections should be merged. This field is only visible if the Length field above is > 0.
TempTol Input The temperature tolerance for determing if adjacent sections should be merged. This field is only visible if the Length field above is > 0.
MFracTol Input The mass fraction tolerance for determining if adjacent sections should be merged. This field is only visible if the Length field above is > 0.
WarningCount Input The maximum number of sections into the which the Conveyor Belt can be divided before the user receives a warning.

BeltDrive

Tag / Symbol Input / Calc Description/Calculated Variables / Options

Power Draw

Power.CalcMethod None The power draw is not calculated. No further fields relating to Power will be visible.
Simple (Ref FullLoad) This method uses simple interpolation between no load and full load to calculate the power draw.
Simple (Ref SpillLoad) This method uses simple interpolation between no load and the spill load to calculate the power draw.
CEMA This method uses the belt configuration and loading to calculate the power draw. It is based on a graphical method described in a book by the Conveyor Equipment Manufacturer's Association. Please refer to Model Theory for more information.
The following fields will be visible for Power Calculation Method = Simple (Full and Spill loads)
Power.Efficiency Input The efficiency of the belt drive.
Power.NoLoad Input The power draw with no load on the belt.
Power.RefLoad Input The power draw with the belt fully loaded, if the user has chosen Full load. Or at the Spill load point, if the user chose Spill Load.
IdealPower Calc The calculated power draw of the belt drive, before adjusting for efficiency.
Power Calc The calculated power draw of the belt drive, after adjusting for efficiency. Power = Ideal Power * Efficiency.
The following fields will be visible for Power Calculation Method = CEMA (Please refer to Model Theory for more information)
Power.Efficiency Input The efficiency of the belt drive.
Power.BeltWidth Input The belt width.
Power.BeltDensity Input The density of the empty belt.
Power.BeltElevation Input The change in elevation between the discharge and feed points of the belt.
Power.EmptyLoading Calc The calculated loading of the empty belt. This is a function of the density of the empty belt (Power.BeltDensity) and the belt width (Power.BeltWidth).
IdealPower Calc The calculated power draw of the belt drive, before adjusting for efficiency. It is the sum of the power to drive the empty conveyor, the power to elevate the material and the power to convey the material.
Power Calc The calculated power draw of the belt drive, after adjusting for efficiency. Power = Ideal Power * Efficiency.

Speed

Type Power & Speed If the power source is available the conveyor will run at the user specified speed.
Fwd Rev The user may specify if the conveyor is running forwards or in reverse.
Soft Start The user may specify the time taken to start the conveyor after it has received a run signal.
Soft Start/Stop The user may specify the time taken to start the conveyor after it has received a run signal and the time for it to come to a complete stop once it has received a stop signal.
Mode Simple  
Command (Latch)  
Command (State)  
FwdRevMode FwdOnly This field is only visible if the Soft Start/Stop Type is chosen.
Logic  
Regulation  
Run/State/Enable/Permissive Tick Box The conveyor Belt is run enabled. The field name used will depend on the Type and Mode chosen.
Invert Tick Box This field is only visible if the Simple Mode is selected. It is not available for Type = Power & Speed. It inverts the direction of the belt.
Start Tick Box This field is only available if Command(Latch/State) Mode is selected.
Stop Tick Box This option is only available if Command(Latch/State) Mode is selected.
StartInvert Tick Box This option is only available if Command(Latch/State) Mode is selected.
StopInvert Tick Box This option is only available if Command(Latch/State) Mode is selected.
Reverse Tick Box This field is only available for the Soft Start/Stop Type conveyor with the Logic FwdRevMode. This reverses the direction of travel of the conveyor belt.
Running Tick Box This displays the state of the conveyor belt.
Tripped Tick Box This allows the user to emulate the tripping of the conveyor belt for logic testing.
StartTime Input This field is only available for the Soft Start and Soft Start/Stop Type conveyors. It is time taken for the conveyor to go from 0 to 100% speed.
StopTime Input This field is only available for the Soft Start/Stop Type conveyor. It is the time taken for the conveyor to go from 100 to % speed.
Forward Tick Box This field is only visible for Type = Fwd Rev. If this box is ticked then the conveyor will run in a forward direction.
Manual Input The user may manually override the speed of the conveyor.
Reqd Input The required speed of the conveyor belt.
Actual Calc The actual speed of the conveyor belt.
Regulated Display
MapLo Input This field is only visible for the Soft Start or Soft Start/Stop Type conveyor.
MapHi Input This field is only visible for the Soft Start or Soft Start/Stop Type conveyor.
MapSpeed Calc This field is only visible for the Soft Start/Stop Type conveyor.
LoSpeed Calc Belt is running on low speed. True if speed < LoSpeedLimit
HiSpeed Calc Belt is running on high speed. True if speed > HiSpeedLimit
LoSpeedLimit Input Low speed limit for the conveyor belt.
HiSpeedLimit Input High speed limit for the conveyor belt.
AutoReStart Tick box Auto restarts the belt.
FailMode None There is no user specified behaviour after a fail event.
No Start The conveyor will not start.
No Stop The conveyor will not stop.
No Start/Stop The state of the conveyor cannot be changed.
RunMemory Tick box Enable this to let the unit keep track of running status.

Feeds

Tag / Symbol Input / Calc Description/Calculated Variables / Options
Fd.[FeedStreamTag]... The number of sections displayed here is equal to the number of conveyor feed streams.
StreamTag Display The tag of the feed stream.
Type (the following two options are only available if the 'Fixed or Moving' FeedConnections option has been chosen on the front tab page. Otherwise the type of connection is forced by the choice on the front tab page)
Fixed The feed stream will not move and the user may set the feed distance along the conveyor.
Moving The feed position can move along the conveyor. The user may only set this option if they have enabled at least 1 Feed Drive.
DriveNo Input This is only visible when Type = Moving. It allows the user to assign the appropriate feed drive number to the relevant feed stream.
Pos Input / Calc The position of the feed stream from the start of the conveyor. If the Type = Fixed, then the user may enter this value, otherwise it is a calculated field if the Type = Moving.
If the BeltFeeder option is used then the position will be forced to the start of the belt (0m).
Limited TickBox The user can limit the feed flow rate by enabling this field. This is used to emulate an Apron or Belt Feeder.
FullSpeedCapacity Input Only visible if the Limited option is enabled. This is the maximum capacity that can be fed onto the conveyor. This number will be passed back to the feed stream, thus limiting the flow from a tank or other surge unit to this capacity.
Qm Calc The mass flow rate of the feed stream.

Products

Tag / Symbol Input / Calc Description/Calculated Variables / Options
Pr.[ProdStreamTag]... The number of sections displayed here is equal to the number of product streams connected to the conveyor.
StreamTag Display The tag of the product stream.
Type (only some of the following options may be available depending on the ProdConnections option chosen on the front tab page. For 'Fixed', the first two options are available. For 'Fixed or Moving', the first three options are available. Otherwise the type of connection is forced by the choice on the front tab page)
Fixed The product stream will not move and the user may set the take-off distance along the conveyor.
Fixed At End The product stream will not move and the take-off distance is at the end of the conveyor.
If the BeltFeeder option is used then this is the forced choice.
Moving The product position can move along the conveyor. The user may only set this option if they have enabled at least 1 Product Drive.
Moving (DistributedBins) This option will be forced if the 'Moving (over Bins)' ProdConnections option has been chosen on the front tab page.
DriveNo Input This is only visible if Type = Moving. It allows the user to assign the appropriate product drive number to the relevant product stream.
Pos Input / Calc The take-off position of the product stream from the start of the conveyor. If the Type = Fixed, then the user may enter this value, otherwise it is a calculated field. This field is not visible if the 'Moving (over Bins)' ProdConnections option has been chosen on the front tab page.
BinStart Input Only shown if the 'Moving (over Bins)' ProdConnections option is used. The position of the start of the bin that is being feed by the product drive. This should be less than the total length of the conveyor belt.
BinWidth Input Only shown if the 'Moving (over Bins)' ProdConnections option is used. The width of the bin that is being feed by the product drive. BinStart + BinWidth should be less than or equal to the total length of the conveyor belt.
Removal Input The percentage of product removal. This option will be forced to 100% if the 'Moving (over Bins)' ProdConnections option has been chosen on the front tab page. NOTE: The last product stream must always have 100% removal if the Conveyor belt is not to spill.

Eg: If two product points are assigned and product 1 takes 40% and product 2 takes 60%, then the Removal for Product 1 should be specified as 40% and Product 2 should be specified as 100%.

Qm Calc The mass flow rate of the product stream.

FeedDrives

One page for each feed drive. Please see Product Drive below for a description of the fields.

ProdDrives

One page for each product drive. Similar fields to the BeltDrive tab page.

Tag / Symbol Input / Calc Description/Calculated Variables / Options
Tripper Drive Position
Note: The product drive will only move IF the motor is running and the motor speed > 0%.
Control None The product drive will move forward or in the reverse direction, as governed by the direction of the motor.
For Example: If the motor is running in the positive direction, then the product drive will move forwards until it reaches the maximum position and then stop at that point. When the motor is changed to the reverse direction the product drive will then start moving back to the minimum position. Note: The required position (Reqd) is ignored with this option.
FwdRev The product drive will move towards the required positon (Reqd) and stop when it is reached. If Reqd = *, then the product drive will automatically tranverse backwards and forwards between the minimum and maximum positions.
Full This works the same as the FwdRev method.
Reqd Input This is only used if the user has selected Control = FwdRev or Full. The user enters the required position of the product drive. If * is entered then the product drive will automatically tranverse backwards and forwards between the minimum and maximum positions.
Actual Calc This displays the actual position of the product drive.
Min Input The minimum point along the conveyor length to which the product drive may move, i.e. the point closest to the conveyor feed point.
Max Input The maximum point along the conveyor length to which the product drive may move. This is normally = the length of the conveyor.
MaxSpeed Input The maximum speed of the product drive. Normally this is slower than the travel speed of the conveyor belt.
Motor Please see Belt Drive - Speed for descriptions of the fields.
Preset Values
Preset.Reqd None The Preset command will not affect the product drive motor or position.
Off The preset command will cause the product drive motor to be turned off and position = the user defined preset position.
Forward The preset command will cause the product drive motor to run in the forward direction from the user defined preset position.
Reverse The preset command will cause the product drive motor to run in the reverse direction from the user defined preset position.
Preset.Posn Input The required position of the product drive if the Preset command is enabled.

WtMtrs

Tag / Symbol Input / Calc Description/Calculated Variables / Options
WtMtr.[0]... The number of sections displayed here is equal to the number of weightometers specified on the first Tab.
Pos Input The position of the weightometer.
Loading Calc The loading at this position.
Rate Calc The mass flowrate passing this position.


Loading

Tag / Symbol Input / Calc Description/Calculated Variables / Options
Belt Loading Profile
Load.DistLength Input The number of sections to be displayed in the Belt loading table.
Load.Norm.Method Full Load All loads will be displayed as normalised values based on the Full load specified by the user on the ConveyorBelt tab.
Max Spill Load All loads will be displayed as normalised values based on the maximum spillage load specified by the user on the ConveyorBelt tab.
Current Max All loads will be displayed as normalised values based on the current maximum load on the Belt.
Manual Max All loads will be displayed as normalised values based on a user specified maximum load.
Load.Norm.Max Input Only visible if the user has selected Manual Max. This allows the user to set the manual maximum value for displaying the loading on the Belt.
Mass.Norm.Method Current Max All masses will be displayed as normalised values based on the current maximum mass the Belt.
Manual Max All masses will be displayed as normalised values based on a user specified maximum mass.
Mass.Norm.Max Input Only visible if the user has selected Manual Max. This allows the user to set the manual maximum value for displaying the mass on the Belt.
The first Table shows the Load and the Normalised Load at positions along the Belt. The positions are calculated based on the Load.DistLength chosen by the user.
The second Table shows the Average Load and Normalised Average Load and the Mass and Normalised Mass on sections of the Belt. The length of the sections is calculated based on the Load.DistLength chosen by the user.

Adding this Model to a Project

Insert into Configuration file

Sort either by DLL or Group.

 

DLL:

MatHand1.dll

Units/Links

Material Handling: Conveyor Belt

or

Group:

Mass Transfer

Units/Links

Material Handling: Conveyor Belt

See Project Configuration for more information on adding models to the configuration file.


Insert into Project

 

Insert Unit

Material Handling

Conveyor Belt

See Insert Unit for general information on inserting units.