Rotational Molding and Plastic Parts Finishing

Rotational Molding and Plastic Parts Finishing
Rotational Molding and Plastic Parts Finishing

Rotational molding and plastic parts finishing combine quality manufacturing with value-added solutions. 

Rotational molding is a manufacturing process that produces strong, hollow plastic parts in a variety of shapes, sizes, and textures. Examples include plastic tanks, bins, pallets, housings, vents, manifolds, and mufflers. Rotomolding, as this manufacturing process is also known, can even produce baby changing stations, spine or back boards, shopping cart accessories, and point-of-purchase (POP) accessories.

Rotational molding is cost-effective, but engineers and sourcing managers want manufacturing partners who are more than just parts providers. That’s why Gregstrom Corporation, a rotational molder with over 70 years of experience, offers finishing services that add value to your plastics projects. Examples include CNC and robotic routing, spin welding, and polyurethane foam filling.

CNC and Robotic Routing

Gregstrom uses five-axis CNC routers and six-axis robotic routers to trim rotomolded parts to their final dimensions. With five-axis machining, a cutting tool moves across the X, Y and Z linear axes and also rotates on the A and B axes to approach the workpiece from any direction. Six-axis machining can reduce cycle times even more while trimming larger parts such as automotive and aerospace panels that need to accomodate finished gaskets.

Spin Welding

Spin welding uses heat generated by rotational friction to join thermoplastic parts. This high-speed process is ideal for rotomolded tanks that require leak-free fittings and ports. After a hole is drilled and a fitting inserted, a router spins at 18,000 revolutions per minute (RPM) until melting occurs. At Gregstrom, applications for plastic spin welding include water and wastewater tanks.

Polyurethane Foam Filling

Gregstrom Corporation also has the equipment and expertise to fill custom rotomolded parts with polyurethane foam, a polymeric open-celled material that provides additional rigidity and thermal insulation. Because rotomolded parts such as coolers and back boards have hollow cavities, their design supports the use of polyurethane foam.

Rotational Molding and Plastic Parts Finishing

Gregstrom is a value-added rotational molder with CNC and robotic routing, spin welding, polyurethane and polyurethane foam filling services. We also provide design assistance, tooling services, assembly and testing, and quality assurance. To learn more about rotational molding and plastic parts finishing, contact us.