2. INTRODUCTION
Glass is a mixture of
metallic silicates like
pure sand, soda chalk
and an alkali metal.
It is made with the
mixture of sand and
silicates in a very hot fire
stove called a kiln.
It is a hard brittle,
transparent, translucent
material.
3. PROPRTIES OF GLASS
Extremely brittle , transparent, translucent and
available in different colors.
Has amorphous structure and no definite melting
point.
Not easily affected by air or water and any chemicals.
Absorbs and refracts light.
Can be polished, welded by fusion ,cast into any
desired shape and modify its properties like hardness,
refractive power.
4. SODA-LIME GLASS
Also known as Soda glass or
soft glass.
A mixture of sodium silicate
and calcium silicate.
Cheap and easily fusible at
comparatively low
temperature.
Used in manufacture of glass
tube, bulbs, bottles and other
laboratory apparatus,
window glass etc.
5. POTASH- LIME GLASS
Also known as hard glass
or Bahamian glass.
A mixture of potassium
silicate and calcium
silicate.
Does not melt easily
that’s why fuses at high
temperatures.
Used in the manufacture
of combustion tube etc.
6. POTASH –LEAD GLASS
Also termed as flint glass
A mixture of lead silicate
and potassium silicate.
Fuses easily and turns
black and opaque.
Used in the manufacture
of lenses , prisms,
electric bulbs, artificial
gems etc.
7. COMMON GLASS
COMMON GLASS-
A colored glass that may
be yellow, green or
brown.
A mixture of sodium
silicate, iron silicate and
calcium silicate.
Does not fuses easily but
attacked by acids easily
Uses in the manufacture
of medicine bottles.
8. COLOURED GLASS
To produce colored glass,
coloring pigment is added
which is obtained from
metallic oxides, finely
divided metals, carbon,
salts of metal, sulphur ,
etc.
Different colored glass
needs different quantities
of same substance.
Used for window panels,
fancy articles, decorative
tiles , etc.
9. CROWN GLASS
Slightly convex
Free from color and has
finer surface
Made by the process of
blow pipe
Used for special articles
10. SHEET GLASS
Made by blowing molten
glass in to a large hollow
cylinder which is split
longitudinally and then
flattened over a plane
disc.
Used for all engineering
purposes.
11. PLATE GLASS
Very strong and more
transparent
Made by pouring hot
glass on casting table by
process of grinding ,
smoothing and
polishing.
Used for looking glass,
large paned glass for
glazing of shop front ,
wind screen of vehicles.
12. PERFORATED GLASS
Made with the help of
projections attached to
rollers.
Used for panels in
ventilators
13. FLUTED OR RIBBED GLASS
Corrugations on both
sides
Variety of obscure glass
Used for securing
privacy without
obstructing the light of
the sun
14. WIRED GLASS
Wired mesh is put in the
glass while rolling during
manufacture of glass
which keeps the pieces
of glass held together.
Do not shatter into
pieces.
Used for fire resisting
doors and windows.
15. SHIEIDING GLASS
Variety of polish lead
glass
Contain lead oxide as
one of the elements
Used for windows
through which high
radiations are to be
observed.
16. SAFETY GLASS
A celluloid sheet is put
between two sheets of
plate glass and formed in
to one unit . Celluloid
sheet prevents
shattering of splinters
when glass breaks.
17. BULLET PROOF GLASS
Do not allow bullet to
pierce through it.
Made by sand witching
vinyl-resin plastic between
several layers of plate glass.
Thickness of glass vary
from 15mm to 75mm or
even more.
Used for glazing bank
tellers booths and cash
booths, jewellery stores,
display cases
18. CALOREX
Also known as excluding
glass
Heat exclusion property
Opaque to ultra – violet
light
Used in factories,
hospitals, kitchen etc.
19. INSULATING GLASS
Very high resistance to
heat flow
Provide insulating effect
It is made of two or more
plates of glass separated
by 6mm to13mm of
dehydrated captive air.
Edges are sealed of the
glass.
20. ULTRA – VIOLET RAY GLASS
Made of raw mixture of
iron titanium and
chrome.
Can transmit 75% of
ultra – violet radiation
more than common
glass.
Widely used in window
pane.
21. LAMINATED GLASS
When breaks , does not
fly off in splinters.
Two or more sheets of
glass are attached with
plastic resin between
them.
Ensures safety at places
where glass is liable to
shatter.
22. FIBRE GLASS
Soft to touch and flexible
in nature.
Made of minute glass rod
.
Developed in in the form
of continuous strands or
in staple form.
Used for chairs, roofs.
23. GROUND GLASS OR OBSURED
GLASS
Made by grinding one
side of the glass or
melting powdered glass
upon it.
Used where light is
required without
transparency therefore
useful for public toilet,
office doors, partition
etc.
24. TEMPERED PLATE GLASS
Much stronger than
ordinary glass
Made by glass plate
which is heated then
cooled to temper it
immediately.
Used for glazed entrance
doors, making table
tops, shelves, counters
etc.
25. SOLUBLE GLASS
Soluble in water
Made by melting quartz
sand, grinding and
mixing it with soda ash,
sodium sulphate or
potassium carbonate.
Used for making acid –
resistant cement.
26. FOAM GLASS
Can be cut like wood
Floats in water
Fire proof, ,rigid and
excellent heat insulator.
Glass and carbon are
finely ground and
mixture of both melted
in a furnace then takes
the form of a block foam.
27. GLASS WOOL
It is available in loose
fibers, quilts, mats, rigid ir
semi rigid slabs.
Thin fibers of glass which
are flexible and have high
tensile strength are spun
out of molten glass.
Used as filter in air
conditioners for electric
insulation , for filtration of
corrosive liquids.
28. GLASS BLOCKS
Hollow transparent units,
made by fusing together
two pressed semi – blocks.
Sizes – 10cm thick and
15cm, 20cm, 30cm square
Sealed edges with grit
bearing plastic so that a
good bond is provided
with mortar.
Used in the construction of
non- load bearing external
panel walls and partition
walls, skylights, insulation.
