Heat treating glass is our specialty: We are pioneers and have built our reputation on
strength and consistent quality throughout the industry. HGP heat treated glass is
available either Tempered or Heat strengthened.
HEAT STRENGTHENED
(Kind HS) is generally twice as strong as annealed glass of the same thickness and
configuration. When broken, the fragments are generally somewhat larger than for fully
tempered glass, and should be considered for areas where there is concern for glass
fall-out as it tends to stay in the opening better than tempered glass. Heat strengthened
glass is intended for general glazing where additional strength is desired but not requiring
the strength of fully tempered glass. Heat strengthened glass is NOT a safety glazing
product.
FULLY TEMPERED
(Kind FT) is over four times as strong as annealed glass of the same thickness and
configuration. When broken, it breaks into innumerable small fragments of more or less
cubical shape. Intended for general glazing and safety glazing such as sliding doors,
storm doors, building entrances, bath and shower enclosures, counter tops, showcases,
interior partitions, and other uses where the superior strength characteristics and safety
properties of fully tempered glass are required.
PROCESSING
The heat treating process requires that all cutting, drilling and edge grinding fabrication
be completed prior to heat treating. Heat treated glass is manufactured by heating
annealed glass to a temperature of approximately 1150 degrees F, then rapidly cooling it
by blowing air uniformly onto both glass surfaces simultaneously. The color, clarity,
chemical composition and light transmission characteristics of the glass remain
unchanged during the heat treating process. The physical properties of the glass such as
compressive strength, hardness, specific gravity, expansion coefficient, softening point,
or its thermal conductivity also remain unchanged. The physical properties affected from
heat treating are the significantly higher compressive surface stress and an increased
bending strength.
All of our plants heat treat glass - it's our specialty. We use horizontal rollerhearth furnace
tempering technology to ensure a high level of quality and performance. HGP heat treated
glass is available in 1/8" to 1 " thickness in clear, tinted, reflective or patterned glasses.
Not all glasses are available in all thicknesses; thicknesses greater than 1/2" are
available in clear only.
THERMAL RESISTANCE
HGP tempered glass withstands approximately 500 degrees F, but is not classified a fire
retardant by Underwriters' Laboratories.
LABELING
HGP tempered glass is permanently marked with our logo in a corner of the lite unless
otherwise specified. |
