Cube Moulding in a Clean Room
Wilden AG employs cube moulding for production of the “HandiHaler“ inhaler. The moulds are especially well-suited for high-speed, economical production of large quantities.
The inhaler consists of eight different plastic parts and four purchased parts. The primary component is the two-component housing of ABS into the sides of which two windows of transparent ABS are integrated. The user can thus see whether the inhaler contains a medication capsule without having to open the unit.
Wilden AG, Regensburg, currently manufactures the inhaler in Pfreimd and plans additional manufacturing in Peachtree City, Georgia/USA in the future. This will allow the largest markets in the world – Europa and North America – to be supplied locally.
The inhaler is produced and assembled in a Class 100,000 clean room. Each of the assembly lines has a capacity of 12 million parts per year and is designed to comply with CFR 21 Part 11 in order to produce for the American market. Wilden employs a special laser technique for surface decoration. In addition, welding of the filter has been improved. A six-arm robot removes the moulded parts from the mould and places them on a conveyor belt for cooling. This minimises the danger of scratching or damaging the housing.
Use of cube moulds is essential for the economics of the production process. The center block of the mould rotates around a vertical axis and contains identical cores on all four faces. After every moulding cycle, the block rotates 90°. Since all four faces of the cube can be used, twice as many cavities are possible. Two of the four faces of the cube remain accessible even when the mould is closed. This means that moulded parts can be removed without an loss of time.
Thus, cube moulding achieves higher productivity than conventional multi-component technology. Depending on the particular application, production costs are reduced by as much as 25%. The benefits of cube moulding are especially evident when large quantities must be produced via multi-component moulding. Wilden has employed this technology for technical plastic systems already for some time now.