Lab System Targets Large Part, Process Development for Combo Injection Molding, PUR Coating | Plastics Technology

Oct 16, 2024

KraussMaffei has paired an MXW 4500 injection molding machine featuring more than 5,000 tons of clamp force with two RimStar polyurethane (PUR) metering systems and three different mixing heads in a new ColorForm lab line at its facility in Parsdorf, Germany.

KraussMaffei’s ColorForm process — where coloring of parts is done directly in the injection mold via introduction of a polyurethane or polyurea layer (PUR/PUA) coating — has a new large lab line for product and process development at the company’s site in Parsdorf, Germany. In this new setup, an MXW 4500 injection molding machine (with more than 5,000 tons of clamping force) has been paired with two RimStar metering systems and three different mixing heads, with a maximum PUR discharge of up to 500 g/sec. (17.6 oz./sec.) possible.

KraussMaffei says it designed the lab line to mimic a complete all-in-one production process, including injection molding, PUR flooding, parts handling, postprocessing and surface treatment, with the ability to run medium and very large components. The production of sample plates is also possible.

To support this, the MXW 4500 machine features a swivel plate and widened clamping plates. A RimStar Flex 8/8 metering system with MK5/MK8 mixing heads handles quantities of up to 50 and 250 g/sec., respectively. A RimStar Compact 16/29 with the newly developed MK10-3K mixing head is also available, providing output rates of up to 500 g/sec. Depending on the component weight, the paint is added via a modular dye module, with the 2K mixing pots, or directly, as with the MK10-3K.

In terms of handling, the automation was also designed with practicality in mind. Because nonconductive plastics like PP, PA and PE need to be “activated” to ensure adhesion between the thermoplastic and polyurethane, a flame treatment station is integrated into the lab system. Postmolding, the system also includes a trimming cell, which can be used to remove sprues or perform other secondary functions.

KraussMaffei has installed an MXW 4500 injection molding machine that supports its PUR overmolding Colorform process in a lab in Parsdorf, Germany. Source: KraussMaffei

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