The insulated structure for annealing glass.
Controlled temperature oven, usually electric, for cooling glass at a controlled rate to relieve strain than will break glass cooled quickly. Usually built by worker as volume is needed and temperature range is relatively low (900-500.) Needs controller. See fire brick and ceramic board, fiber & blanket
a heated box with careful temperature control
a metal box with insulation inside
a space with a carefully controlled temperature that allows the glass to cool slowly so that strains are released and not re-imposed during cooling
insulated box where finished pieces are allowed to cool slowly to remove strain and prevent breakage.
Works made from hot glass need to cool slowly to room temperature, otherwise stresses will develop and they will crack. An annealer (or lehr) is a large oven used to slowly cool the glass from around 900F to room temperature. Typically a 24 hour program is used; if thicker work is made, then a longer program is required.
An oven to put finished pieces where they can gradually cool. Hot glass must cool down slowly or it may crack and shatter. Annealers come in different sizes. A large one may look like a big pizza oven lined with heating elements and insulation. It takes twenty minutes for an annealer to heat up to a working temperature of 895 degrees Fahrenheit. A small computer regulates the gradual reduction of the temperature.
