Auxiliary Equipment (November 01, 2009)
Maguire's MGF gravimetric feeder provides accurate dosing by using load cells to monitor the loss in weight of colorant in the hopper as the material is fed into the injection molding machine or extru...
Maguire’s MGF gravimetric feeder provides accurate dosing by using load cells to monitor the loss in weight of colorant in the hopper as the material is fed into the injection molding machine or extruder by an auger.
The unit has multilingual operator access and full data retrieval as standard features for all molding and extrusion applications, plus a new “extrusion following” option that automatically anticipates and adjusts for gross variations in extruder rate like those during changes of film rolls.
Installed in the controller of the MGF feeder, the extrusion following system monitors the AC or DC voltage output from the tachometer that is standard on most extruders. Because this output varies with extruder RPM, the controller instantly senses gross changes in extruder speed and adjusts the color or additive metering rate accordingly, avoiding the falloff in accuracy that otherwise occurs while the controller “catches up” with changes in rate.
Calibration of the extrusion following system needs to be done only once. The processor simply sets the metering rate for full extruder speed. Anything less than full speed is automatically reflected in a corresponding reduction in metering rate. Voltages from 1 to 500 can be tracked, with accuracy maintained over the full range of extruder speed.
Maguire Canada/Novatec Inc. (Vaughan, Ont.);