Diseño de snap-fit para inyección de PP

Author

Riera Golobart, Sergio

Abstract

A snap-fit is an integral hook mechanism to fix one piece with another. The most important criterion for pressure adjustment is flexibility, this can be large or small depending on the type of blockage. For this reason, the most used material for these mechanisms are plastic materials. Plastic processing technologies such as injection molding allow to obtain economically viable complex shapes. This technique allows to obtain a very good cost-efficiency ratio since it reduces assembly time and minimizes the number of parts needed because the coupling parts are molded directly at the same time as the components, both being of the same material .
Much more engineering is required to design a snap-fit, than to design something to assemble with screws. That is why there are numerous guides for the design of snap-fits, such as Basf-Plastics [1] or The Firts-Snap-Fit Hanbook [2], which establish a series of design guidelines to get the most out of properties of plastic materials.
This study focuses on the structural optimization of a cantilever snap-fit for PP injection in order to determine which dimensional parameters have a greater impact on stress and strain analysis.
For the optimization of design and manufacturing, the Simulation and Plastics modules of SolidWorks 2018 from Dassault Systems have been used and the results obtained have been compared with the classical beam theory and the Basf-Plastics method. Finally, 4 snap-fit prototypes have been manufactured per 3D printing and the clipping forces measured.

Director

García Granada, Andrés

Degree

IQS SE - Master’s Degree in Industrial Engineering

Date

2020-03-18