What is rotational Molding? Rotomolding is a technique for manufacturing plastic parts whose main characteristics are its durability and resistance. They are hollow and resistant pieces with wide uses in different industries such as automotive, toy, and storage, among others. The process dates back to the sixties and remains at the forefront to date.
The breadth of uses and the adaptation to various raw materials makes it very versatile, hence its use in such different industries. Besides, it is a process of easy adaptability, with the right design, you can build almost anything with screw molding. Its name comes from the use of one or two lathes or shafts that rotate as the mold heats up.
This process is preferred in many industries over other better-known ones such as injection molding, blow molding, or thermoforming. Each process has its practical utility, but in many respects, it is surpassed by the tornomolding, with greater advantages.
Advantages of Molding
Rotational Molding has many comparative advantages; one of the main ones is that it has no limitations regarding the size of the pieces. Secondly, it can be considered an ecological product since it can be recycled and reused countless times. Besides, having great profitability for industries, that is, its cost is lower than other processes.
The parts manufactured with the process of tornomolding are hollow pieces with great resistance and durability, with a finish of excellent quality. These are among many other aspects that make more and more industries decide to screw their parts. Industries such as automotive and warehousing have opted for this process for its production and thus reduce costs.
Some manufacturers produce parts for their end products themselves, while others order them from specialists in the field.
The turning process
Part of the Rotomolding Process involves the design of the parts and molds, for this, the specialists work with the designers of each company. In this part of the process, the client’s needs are defined and together they create the test prototype, which will be improved. Once the mold has been made and the prototype has been tested, the Molding has no quantity limitations.
They can be produced from one piece to a huge quantity, which contributes to the profitability of the process for the industry.
The raw material used can be varied and obeys the criteria of each client, variety, and adaptability are part of this process. Some of these raw materials are plastisols, polyurethane, nylon, polycarbonate, fluoropolymers, polypropylene, and elastomers, among others, the most common being polyethylene.
The four stages of the process
The manufacture of parts occurs in four stages, which will be described below in some detail:
- The First Stage: in this Stage, the resin or the ground or pulverized material is inserted into the mold, the mold is hermetically closed.
- Second Stage: once the mold is loaded, it is heated while rotating slowly on two axes so that the resin melts.
- Third Stage: in this Stage, pre-cooling and cooling take place, the mold is cooled by two complementary methods.
- Fourth Stage: once the product is cold, it is removed from the mold, which is cleaned to be used again.
This manufacturing process completes the final products that can be manufactured one by one or on a large scale.