Playground can be made by blow molding and rotomolding.It depends on customer’s requirement.For example,slide.If a slide only whole part usually be made by steel mold.If the design is connecting parts,people may choose aluminum mold.
The most common rotational molds is sheet metal molds.We usually call steel mold.It is mainly used for large and simple structure parts.eg. Water tanks.
In the earlier times,steel mold just need to be simply hammered and welded by hand.But now,the production with more mechanical process.eg. CNC,laser cutting,mechanical stretching,mechanical bending,etc.And the parts can be more complicate.For some ribs and radian parts we did compression mold first to make molds more sooth and beautiful appearance.
