Investigation of thermoforming as a method of manufacturing plastic air intake manifolds
Original Publication Date: 2001-Apr-01
Included in the Prior Art Database: 2003-Jul-23
Current plastic intake manifolds are manufactured using the injection molding process. In this paper, thermoforming is explored as an alternative to injection molding for making intake manifold shells, which can then be joined by one of the welding techniques used for thermoplastic materials. The idea includes press-forming experiments of a simple bowl shaped shell and subsequent welding experiments to join these shells. There are many plastic intake manifolds in production today covering applications ranging from turbo-charged diesel engines to normally aspirated gasoline engines. Current manufacturing technologies for plastic intake manifolds include lost core injection molding, shell injection molding and a small number of assorted other technologies. The shell injection molding process followed by vibration welding has a lower tooling cost and is less cumbersome than the lost core injection molding process. As the use of plastic intake manifolds grows, the shell design becomes more attractive because of its applicability to lower volume economies of scale.