Question

The solidification of a casting starts at 10 AM. However, the solidification of the molten metal at the center-line of the mold starts at 10:03 AM and ends at 10:10 AM. The casting is considered solidified completely when the solidification is completed at the center-line of the mold. The center-line feeding resistance (CFR) in percentage is .............

Hint:

The center-line feeding resistance (CFR) indicates how efficiently the solidification progresses at the center-line of the mold. A higher CFR suggests slower solidification at the center.

Answer 1

The center-line feeding resistance (CFR) is calculated based on the time taken for the solidification at the center-line. The formula for CFR is: \[ {CFR} = \frac{{Time taken at center-line}}{{Total time for solidification}} \times 100. \] Here:
- The time taken for solidification at the center-line is from 10:03 AM to 10:10 AM, which is 7 minutes.
- The total time for solidification is from 10:00 AM to 10:10 AM, which is 10 minutes.
Thus, the CFR is: \[ {CFR} = \frac{7}{10} \times 100 = 70%. \] Therefore, the center-line feeding resistance (CFR) is 70%.