Machinery and Equipment Gravimetric Blenders Prove Themselves at Saturn

Color concentrate consumption was too high and color consistency of parts too low when Saturn Corp., a Tennessee-based auto manufacturer, decided to abandon its volumetric feeding system. Twenty-three injection molding machines at the Tennessee plant were using volumetric feeders mounted on the machine to introduce color concentrate.

Before selecting a gravimetric blender to replace the volumetric units, Saturn engineers established detailed criteria for the new units and set up a three-month, on-machine trial of blenders from three suppliers.

The blenders had to prove themselves by cutting costs through reduced concentrate consumption, and had to provide accurate, consistent color.

Blenders operated under test for three months in actual production.

When the testing was complete, Mould-tek Industries Inc. was the chosen supplier. Its GXB blender proved to be the easiest to operate and most reliable during testing.

“The pinch valve design of the GXB blender made it more accurate and easier to control. It also required less maintenance,” said Becky Schwind, the engineer in charge of the Saturn test.

With the GXB blender, color concentrate usage dropped to three percent, from a high of 10 percent, and color consistency improved substantially. CPL