Sterling 882.00274.00 specifications Extruder Tracking Equation, Example

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6.Determine the desired additive feeder setpoint (% of extruder (master) screw RPM). To determine this, you must know:

•Total extruder feedrate (lbs./hr.).

•The RPM of the extruder screw at that feedrate.

•The letdown ratio of the additive (% or :).

•The additive feedrate required at that letdown ratio (total feedrate X letdown ratio).

•The additive feedrate RPM needed to achieve this feedrate (as determined by the calibration procedure).

Extruder Tracking Equation:

Set Point = (rpm of feeder / rpm of extruder) x 100

Example:

Total extruder feedrate = 500 pounds per hour Extruder screw rpm for 500 lbs/hr = 50 rpm Additive letdown percentage = 7% Additive feedrate = 500 X 0.07 = 35 lbs./hr.

Feeder auger rpm needed for 35 lbs./hr. = 44 rpm (as the calibration procedure has shown)

Assuming this, set point = 44 rpm/50 rpm x 100 = 88 or 88% of the extruder screw speed.

Additive Feeders

Chapter 4: Operation

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Contents SF Series Additive Feeders Parts and Service Department Shipping Information Table of Contents Troubleshooting How to Use This Manual SafetySafety Symbols Used in this Manual Wear Safety Glasses and Work Gloves Responsibility General ResponsibilityOperator Responsibility RememberMaintenance Responsibility Reporting a Safety DefectStandard Features Mechanical FeaturesFunctional Description Models Covered in This ManualController Features Electrical FeaturesOptions Accessories Safety Circuit Standards Safety Devices and InterlocksFail Safe Operation Safety Device Lock-Outs Installation Supply System InstallationUncrating the Equipment Rigging and Placing the Additive FeederElectrical Connections Main Power ConnectionControl Relay Connection Setup Procedures Determining the Desired Feed Rate110 100 Procedure Calibration ProcedureEquipment Needed Examples Observed Feed RatesInitial Start-up Pre-Startup ChecksStarting Up the Additive Feeder Shutting Down the Additive FeederSwitches Indicator LightsOperation Start-upUsed as a Cycle Override Safety Timer Timer ModuleCounter Module Elapsed Time Module Dual Setpoint Control Operation 2 Component Applications Regrind Feeder with Proximity SwitchSet Point #2 Motor Control Bottom Low Level Extruder Tracking Installation and Setup Extruder Tracking ControlExtruder Tracking Equation Desired Display Setting Field Control ProgrammingEquation Motor RPM = 25.2 X Auger RPMViewing or Changing the Constant Programming ModeProgramming for Follower Operation Viewing or Changing the Program Minimum Setting Viewing or Changing the Program Maximum SettingExiting Programming Mode and Returning to Run Mode Program Minimum SettingAdditive Feeder Control Factory Defaults Shutting Down the Additive FeederPreventative Maintenance Schedule MaintenancePhotocopy this page for your maintenance records Preventative Maintenance Material Cleanout/ChangeoverCorrective Maintenance Auger Assembly ChangeoverRemoving Auger Assembly Installing Auger AssemblyMotor Brush Replacement Replacement Motor Brush Part NumbersProblem Possible cause Corrective action TroubleshootingIntroduction Additive Feeders Troubleshooting Warranty AppendixOptional Components Technical Specifications Annex B InformationDrawings and Diagrams Additive Feeder Specifications and Overall DimensionsTypical Additive Feeder Controllers SET Point Spare Parts List Exploded Assembly Drawing Parts ListA0541292 Auger Assembly, 1/2 One Component Control Enclosure Parts Identification Two Component Control Enclosure Parts Identification Safety Tag Information Warranty ReturnsAdditive Feeder Safety Tags Returned Material PolicyAdditive Feeder Identification Serial Number Tag Technical AssistanceWorksheet for Charting Feed Rates Photocopy this page for your records