The standard time-temperature curve is defined by a smooth curve drawn through the following internal furnace temperature points: initial internal furnace temperature 20 °C at the end of the first five minutes 576 °C at the end of 10 minutes 679 °C at the end of 15 minutes 738 °C at the end of 30 minutes 841 °C at the end of 60 minutes 945 °C.
