How are Storage Boxes Made?

If you look at a plastic storage box closely, you'll probably notice there are no seams or joints. In other words, it was made all in a single piece. The process behind this is called injection moulding. It is the same process used to create almost everything we use that's made of plastic. The process is surprisingly simple, making moulded plastic products very inexpensive to produce; thus, the relatively cheap price for storage boxes.

In the injection moulding shop, a mould maker (sometimes called a tool maker) uses a set of drawings to produce a mould. Most moulds used for plastic are made of aluminium or steel. A series of holes will be included to allow a clear path for the plastic material to travel into the mould cavity. When he's finished, the mould cavity will be the exact shape and size of the storage box.

From there the mould travels to a test production area where it is installed in an injection moulding machine for initial set-up. Engineers need to determine how much plastic to inject into the cavity to get the desired product. Tiny plastic beads are fed into the machine through a hopper, where they are melted, mixed, and injected into the mould. Pressure gauges, flow meters, and chronometers all take measurements during this process. When the engineer is satisfied with the finished product, he creates a detailed fact sheet containing all the settings needed to produce the plastic storage on the shop floor.

The mould is then transferred to a production machine and put to work; duplicate moulds are sometimes made for large orders. Operators will tend to the machines, remove the finished storage boxes, and trim any debris left by the injection process. And now you know how plastic storage boxes are made.