Thursday, 24 September 2009

Cooling Events

This is based on Graham Stone’s work with float glass. The temperatures are applicable to float glass, and so need to be adjusted for a particular glass, but illustrate the principle of how heating temperatures affect the glass. Temperatures in degrees Celsius.

600 Common temperature for crash cooling toward. Glass beginning to "freeze".

555 Annealing temperature of float. Bungs in.

515 Approximate Strain Point of float.

535-400 Critical slow cooling down phase for float that overlaps annealing range.

400-300 Medium cooling down ramp rate.

300-10 Fast cooling down ramp rate. Cracking the kiln open possible.

Based on Firing Schedules for Glass; the Kiln Compainion, by Graham Stone, Melbourne, 2000, ISBN 0-646-39733-8, p24