Improving Quality in Mega-Casted Products, Identification of contributors to geometrical variation
Publicerad
Författare
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
When using a process to produce various parts, geometrical variation describes the
differences in deviations among those parts. These deviations arise due to different
factors, and minimizing them contributes to improved consistency in production,
increased overall product quality, and reduced costs in terms of extra rework. This
master’s thesis aimed at expanding the knowledge about high-pressure die-casting
(HPDC) and identifying contributors to geometrical variations. The scope of the
study is limited to larger defects affecting the geometrical accuracy and excludes surface
defects, porosities, and machining. The method used for reaching the goal was
by conducting qualitative and quantitative approaches. A total of 11 professionals
in the area of HPDC were interviewed. Production tests related to the quenching
phase were also conducted in the foundry. The main finding from the study was that
design is the root cause of geometrical variations, as the varying thicknesses induce
residual stresses which in turn influences the accuracy of the final shape. One of the
findings successfully reduced geometrical variation in megacastings but led to other
problems such as sticking to the trim-press. In addition, a DoE was suggested for
future studies. The DoE provides a systematic way of working and helps in finding
the optimal combination of influential and easily changeable parameters.
Beskrivning
Ämne/nyckelord
HPDC, Megacasting, Geometrical variation, Distortions