Rotational molding or rotomolding is a process used primarily to create seamless, stress-free, hollow one-piece items. where a hollow mold is filled with liquid or powder resin and rotated in two directions in a hot chamber, until the resin covers the surface of the mold and is cured to form a piece. It is an economic process that does not require application of stress on the resin to be transformed, and produces hollow plastic articles, without seams, without residual efforts, with a uniform wall thickness and with ample product design possibilities. It offers high production versatility, and represents an interesting option, compared to similar transformation processes, such as injection molding, thermoforming or injection blow molding.
Processes involved are filling the mold, hearting the mold, mold cooling and emptying the mold. Good enough, these rotational moulds are not too costly, they are recommended for entrepreneurs who want to start up small business
The rotational mould is used to make a lot of hollow plastics.
· Piggy banks
· Materials as big as the kayak and any hollow material you can think of.
Used to make various thicknesses of the same mould
There is high flexibility when using rotational moulding, the you don’t need to purchase a different mould for different thicknesses. All you have to do is change the speed of the spinning, and amount of powder or substance to mould. For the material to adhere properly to the mold, the powder must flow easily without any external pressure other than gravity. This property is called fluidization, and is measured by counting the time required for a given weight of the material powder to flow through a standard funnel. If the test procedure indicated in ASTM 1895 is used, a minimum flow rate of 185 grams / minute characterizes powders suitable for rotational molding.
Allow use of multi-tasking
Rotational moulds have various sections and arms which operate independently. where you can place different shapes of moulds for different objects. This helps your moulding works to be faster and efficient. They also allow Multilayer molding (foaming triple layer).
Used to manufacture both large products and small products
Rotational moulding uses low cost tooling. Their parts can be extremely small or extremely large supporting tons of heavy objects and good for any kind of business you need.
Rotational moulds are used to make prints on plastics, you add graphics to the mould before the cooking cycle. The embedded graphics lasts on the object moulded for its life time, you just have to make sure that the cooling process is carried out carefully.