What is Rotational Molding?
According to the Association of Rotational Molders, rotational molding (a.k.a. casting, rotomolding) is a low-pressure process that produces hollow, plastic parts. The Plastic Professionals further explains that either powder or liquid resin is placed into the mold. Next, molds are placed into a convection oven, where they are rotated on both the X and Y axes. This is a slow process: at eight revolutions per minute, it can take up to 3 hours to complete one mold.
What are the Benefits of Rotational Casting?
1. Cost Savings: According to the The Association of Rotational Moulders Australasia, rotational casting can save money both in preparation for and during the process. Molds are relatively inexpensive. There are no wasted materials since all materials are used in making the parts. Finally, short production can be economically viable.
2. Design: Unlike other molding processes, rotational molding can be used to design almost any shape. R&R Technologies explains that products can be made with sizes that range from Ping-Pong balls to tanks that can hold 21,000 gallons. The plastic heated during the process will melt and take shape of the mold it’s in. The process also creates uniform wall thickness. The ability of the process to take the shape of the mold and texture results in high-quality surface finishing. Finally, high quality graphics can be molded onto the product’s surface.
3. Tooling: Rotational casting utilizes tooling that is less expensive and quicker to produce when compared to other processes like blow molding. The Plastics Professionals discuss tooling choices, and include:
-Billet Rotational Molding Tooling: Typically the most expensive rotational molding tooling, a machine utilizing an automated computer numeric controlled (CNC) process is used to cut into the aluminum billet.
-Cast Rotational Molding Tooling: The most common type of rotational molding tooling, designs can be prepared in 6 to 8 weeks.
-Fabricated Sheet Metal Tooling: Used with large parts that don’t have complicated designs, fabricated sheet metal tooling is welded together and is often the least expensive tooling option.
4. Versatility: Rotational molding can be used in many applications. Apart from what we’ve already mentioned, this process can handle complex shapes, moving parts and parts made from different materials. During the rotational casting process, metal inserts can be accepted and also has the possibility of accepting additional insets. Additional advantages include the ability to create multi-layered walls.
Overall, there are many advantages to the rotational casting process. Its versatility in terms of design and component compatibility allows for the creation of products that serve a variety of industries. The Association of Rotational Molders explains that some products created using this process include:
-Medical Specimen Cases
-Water Filtration Units
The Mark Tool Difference
Our state-of-the-art technology separates us from other machining and fabricating companies. We’ve incorporated a new high-speed procedure that applies a hybrid urethane at high speeds. This eliminates the need to build molds for each casting, thus reducing tooling expenses. Contact us today so we can discuss your specific needs.