Transfer & Injection Moulding Presses

Today, combination of injection molding press and twin-screw compounding extruder represents new paradigm for processors, creating their own material whole they mold them. Though these machinery systems are expensive, these are able to successfully provide :

• New opportunities for materials cost savings
• Flexibility to tailor formulations for individual parts

With molder taking responsibility for raw materials and molded parts, adding complexity to process multiplies number of variables to control. But even then, these machines have established a growing niche and demand in the market.

Presently, what started out a decade ago as way to reduce costs of molding long-glass thermoplastic composites for structural automotive parts has today also spread to non-automotive applications including other types of compounding and alloying task. Some of the machine areas that got recent upsurge in this field include:

• In-line compounding and injection molding
• Direct Long-Fiber (Reinforced) Thermoplastic processes (for in-line compounding-and-molding)

To match these, either compression or injection processes are aimed at assisting thermoplastic composites compete more cost-effectively with thermoset SMC. With DLFT developed to be lower cost than glass-mat thermoplastics (GMT) and long-fiber pellets produced by thermoplastic pultrusion method, both GMT as well as long-fiber pellets need proprietary processes to produce intermediate raw material in sheet/pellet form. Further, GMT has additional disadvantage of producing substantial amounts of scrap which cannot be reused in that process.

With first DLFT processes separating compounding and molding steps and required manual/robotic transfer of hot compound to press, the latest step introduced in this line is aimed towards integrating compounding and molding on injection machine so as to effectively provide

• Greater automation
• Shorter cycles than can be achieved with compression molding