GUANGZHOU, May 21, 2007 - A new-generation device for feeding colorants and
additives into plastics processing machines combines the low cost of a
volumetric feeder with the superior precision, consistency, and data generation
of a gravimetric metering system, Maguire Asia announced today at Chinaplas 2007
(Stand 1D-301).
The enhanced accuracy of new MGF Series gravimetric feeders enables molders
and extrusion processors to reduce color and additive consumption, increase
control over product quality, and document color usage for each production run,
according to Marshall Guo, general manager of Maguire Asia’s Shanghai-based
Maguire China operation. The feeders are available with throughput capacity of
up to 16 kg per hour and can be mounted directly to the throat of most molding
machines or extruders. They are backed by a five-year warranty.
While Maguire ships hundreds of volumetric feeders each year, the new MGF
Series feeders are its first gravimetric systems. “Until now, gravimetric
feeders have been specialty devices available from a few suppliers and costing
40% more than our volumetric equipment,” said Mr. Guo. “All that changes with
the MGF feeder, which provides processors with the cost-reducing accuracy of a
gravimetric feeder for the price of a volumetric model.”
While an MGF feeder is mounted on the processing machine exactly like its
volumetric counterpart, there are two major differences between the systems: 1)
The MGF feeder has two load cells which accurately monitor the loss in weight of
colorant in the hopper as the material is fed into the processing machine by an
auger. The hopper and auger tube are mounted atop the load cells. 2) The MGF
feeder has an easy-to-use microprocessor controller with backlit display. The
controller allows all dispensing parameters to be easily entered. Automatic
adjustments are made when 20 grams of accumulated error is detected.
The loss-in-weight operation adds a new dimension of accuracy. “Volumetric
feeders do not monitor the weight of colorant as it is fed to the processing
machine and thus generate no data about how much of the material is actually
consumed from moment to moment,” Mr. Guo said. “Because a gravimetric system
generates a wealth of data on color consumption, it adjusts color metering far
more accurately to account for process variations and to compensate for
vibrations on fast-cycling molding presses.”
New Gravimetric Feeders Readily Adjust for Process Variations
The controllers for the new MGF feeders have a digital counter that the operator
uses to pre-set the precise amount of color to be added. This parameter is
translated into the required degree of auger rotation.
In injection molding, the operator inputs the shot size and letdown ratio for
the specific application. The auger doses color as the screw in the molding
machine retracts, and the auger motor shuts off when the required amount has
been supplied. Drawing on information fed back from the injection machine, the
controller adjusts for screw slippage or changes in rate.
In extrusion, the operator inputs throughput rate and letdown ration. The
controller regulates auger motor speed to automatically adjust for changes in
screw torque, plant voltage, or raw material.
By tracking and adjusting for actual colorant consumption, the MGF feeders not
only provide even greater accuracy and consistency but also make possible
detailed documentation of the entire production run, according to Marshall Guo,
including a shot by shot account of color dosing in injection molding. The new
feeders can be linked in a plant-wide network.
The MGF feeders also retain the user-friendliness of the volumetric feeders. For
example, every component that comes into contact with colorant is easily removed
for fast cleaning.
MAGUIRE PRODUCTS ASIA PTE LTD. is headquartered at 45 Kallang Pudding Road,
No. 01-02 Alpha Building, Singapore 349317. Tel: 65-6848-7117. Fax:
65-6744-3370. Email: magasia@maguire-products.com.sg.
MAGUIRE CHINA is headquartered at 7C-02 Majesty Building, 138 Pu Dong Avenue,
Shanghai 200120. Tel: 86-21-588-23410. Fax: -23420. General manager is Marshal
Guo. Email: mpa@maguirechina.com. Other China offices are in Beijing, Guangzhou,
Xiamen, and Suzhou.
MAGUIRE PRODUCTS, INC., headquartered in Aston, Pennsylvania, U.S.A., is the
world’s largest supplier of gravimetric blenders and liquid color pumps and also
manufactures loading systems, granulators, dryers, auger feeders, and related
equipment and software. Its customers include injection, blow, and rotational
molders, extrusion processors, and compounders. Founded in 1977, Maguire
operates five manufacturing facilities in Aston and Smithfield, Rhode Island,
U.S.A. The company maintains a network of distributors in the Americas and
overseas and has two sales and service subsidiaries: Maguire Europe, which
supports customers throughout Europe and operates a distribution center in
Tamworth, Staffordshire, United Kingdom; and Singapore-based Maguire Asia,
serves customers throughout South Asia and the Pacific Rim. Visit the Maguire
Products web site: www.maguire.com
