Posted by
Sunhouse Glass on Friday, March 27, 2009 11:00:00 AM
Tempered glass and standard glass differ in the way they are processed. To
manufacture any glass; sand, soda ash and
lime are mixed together and melted at very high temperatures. This hot liquid
is formed into glass by the methods of
blowing, pressing, or drawing. Once glass
is formed, it goes through an annealing process where it is reheated and
cooled. This keeps it from shattering and restores its strength.
The annealing or
cooling process is what determines whether glass
will be tempered or standard. Tempered glass is forced to cool very
rapidly while standard glass is allowed
to cool slowly. Standard glass’s slow
cooling produces different properties than those found in rapidly cooled tempered glass.
Tempered glass is often called toughened, or
strengthened, glass as it can withstand
at least four times the pressure of standard glass.
The most notable property of tempered glass is how it shatters or
breaks. Standard glass breaks into
large, irregularly shaped sharp shards. Tempered
glass, shatters into small evenly shaped
pieces that pose much less risk of injury to those coming in contact with them.
Tempered glass is more
heat-resistant and scratch-resistant than non-treated glass. Outwardly, tempered glass
does not appear any different than standard glass.
Both types of glass are made in varying
sizes and thicknesses and can be colored or tinted.
Standard glass can be cut to size or pressed into shape
after it is processed. If an application requires, standard glass’s edges can be polished or holes drilled
into it. Strengthened glass can not be
reworked after it is tempered. Attempts
to cut or drill into a pane of tempered glass would result in it shattering
completely.
Because it is
stronger and its fracture pattern safer than ordinary glass, tempered
glass was once the standard for car
windows and glass doors.
Nanjing SunHouse Glass Co., Ltd. is specialized in manufacturing tempered glasses.