|
|
|
|
We generally prepare and test two molds at a time. The photograph above shows the two molds, both in a horizontal configuration, connected to the data aquisition system and ready for pouring.
Below is a snap of what we see on the screen during the casting. Two groups of signals can be seen in the photo - these correspond to the two molds. These are the temperature histories within the molds.
woodbury@me.ua.edu |
Each
of the molds has eight thermocouples - four in the top of the mold and four in the
bottom. Here Chris connects the thermocouples to the data acquisition system
with subminiature thermocouple jacks. The thermouple extension wires shown in the
photo at left are overbraided with stainless steel - this has proven useful on at least
one occasion when some molten aluminum was spilled during a test!
The
data acquisition system is based around an 83MHz Pentium (OverDrive) computer running
Windows95. The software is National Instruments Labview, and we have a customized
"virtual instrument" (.vi file). The hardware is also from National
Instruments, and consists of a 16-bit A/D board (inside the PC), and an external SCXI
chassis (beside the PC in the photo) which contains a thermocouple input board. This
board allows for up to 32 thermocouple channels to be recorded simultaneously. It
also provides high frequency noise filtering and amplification of the relatively
low-voltage thermocouple signals.
