Árbók VFÍ/TFÍ - 01.06.2000, Side 332

330 Árbók VFÍ/TFÍ 1999/2000
Casting Mould Analysis
In order to investigate the geometrical
design of the mould a 3D model of the
current mould design and boundary
conditions is simulated. A model using
the same geometry but different bound-
ary conditions is also simulated and
compared to the current boundary con-
ditions. The different boundary condi-
tion is no water cooling of mould edges
during FeSi water cooling.
The mould is described with respect Figure 8. 3D element model ofthe mould.
to geometry, time dependent boundary
conditions and loads.
For simplifícation mould comers are set rectangular. A quarter of the mould is modeled,
i.e. the lower right part seen in figure 2. Other parts of the mould are not considered in this
study. Figure 8 depicts the element model.
Model Simulations
The 3D model is used to simulate a one cycle two layered casting process based on the one
layered casting process of table 2. This process will be referred to as process 2.
Current Process
Figure 10 and 11 show the temperature and equivalent stress during process 2 at dififerent
points in the symmetry cross section of the mould as shown in fígure 9. The temperature in
Pl is in good comparison with the onc-dimensional case. Thc temperature in P2 also shows
an expected behavior being closer to the mould side and more effective cooling. The tem-
perature curves for P3, P4 and P5 represent well the effect of the edge water cooling during
FeSi water cooling. The temperature drops swiftly during water cooling and rises relatively
fast afterwards, due to heat flowing from the hotter core. The temperature in P6 is not
affected by the casting sub-cycle and the temperature rises gradually.
Figure 9. Points in mould symmetry cross section used for plotting of temperature and equivalent
stress.