Blow-moulded cases are plastic cases manufactured in a special production process – the blow moulding technology. These cases are double-walled, i.e. the outer and inner cover can be produced at the same time during the production process.

The production process:

The blow moulding technology is a process to produce a three-dimensional hollow body from plastic granulate, e.g. the fuel tank of a car or the seat board of a swing.

Thick plastic material is pressed through a round gap of a mould that is attached to an extruder cylinder (the so called blow head). The gap´s diameter and the weight must be matched to the object to be moulded. First, the machine creates a "plastic tube". The process of heating the plastic and pressing the material through the round gap is called extrusion. The "plastic tube" is placed in a mould consisting of two parts. To form the blow-moulded article, the correct amount of the hot “plastic tube” has to be separated and placed into the tool. Once separated, the tool is positioned over a “blow mandrel” which dips into the end of the tool and blows air into the hot plastic. The “plastic tube” is pressed apart and nestled against the inner wall of the tool. Afterwards, the material has to cool down and solidify. The mould opens and moves back to the “blow head”. The “blow mandrel” is removed from the hollow body, the tool parts can move apart and release the hollow body.

The application:

The production process described above makes it is possible to create case parts that possess an outer and inner cover in one work process. Usually, two mould variants (for upper and lower part) are needed per complete case. This production process is advantageous for case solutions in combination with a foam inlay with regard to low unit costs. Due to the high durability of the cases, they have become popular for the transport of manual machines, e.g. drilling machines. Basically, machines and tools used on construction sites are often transported in blow-moulded cases.