Manufacturing Processes 71
Automated glassware forming
The
production of glassware items, such as
wine glasses or tumblers, is an automat-
ed variation of traditional glass blowing.
A pipe is used to gather molten glass,
form a parison, and blow the glass into a
mold. The forming process is followed by
finishing processes, which include stem
forming or waste glass trimming.
Blow and blow
A process in which
molten glass is placed into a mold where
a parison with a finished neck is created.
Air is used to form a parison, which is
removed from the mold and transferred
to a blow mold, where air is used to form
the final shape.
03
GLASS PROCESSES
Glass processes are used in the design and manufacturing of consumer, commercial,
and architectural products. Contemporary manufacturing of glass is focused on refin-
ing traditional processes and glass formulations for high-tech uses.
After a design is developed, an appropriate glass type and forming process is
selected. These choices are made based on the application and desired properties.
This section provides important terminology related to glass manufacturing.
1.
Molten glass
dropped into
blank mold
2.
Neck
formed
3.
Blank
blown
4.
Blank
shaped
5.
Blank
transferred
to blow
mold
6.
Final
shape
blown
BLOW AND BLOW
2
Job on:93996 CTP Title : RP_Process Material Measurements Client : Pro_Vision
Scn :
#
175 Size : 146.05(w) 209.55(h)mm _M2_Mac D
Dept : DTP D/O : 16.12.05 (Job on:000000 D/O : 00.00.01 Co: CM0)
Pantone
109 U
p71
93996_PM&M_066-129_M2.qxd5 16/12/05 12:43 PM Page 71
R
O
e
c
o
w
i
3
o
h
f
p
t
a
i
t
a
03
72 PROCESS, MATERIALS, AND MEASUREMENTS
Container forming
Automated container
manufacturing is a multistage process.
First, raw glass is heated until molten.
Next, the glass is formed in two steps.
Then, containers are annealed and
cooled. Finally, the containers are inspect-
ed and labeled. There are two common
forming processes for glass containers.
Glass blowing
Historically, glass blowing
has been the most common method of
forming glass. A hollow pipe is dipped
into molten glass. The pipe is rotated to
gather glass and then rolled on an iron
slab to form a parison. Through the
process of rolling on the slab, reheating,
and blowing air into the tube the parison
is shaped into a hollow form. Iron or
wooden molds are used to create the
final shape of the object.
Press and blow
A process in which
molten glass is placed into a mold and is
pressed by a plunger to create a parison.
The parison is removed and transferred
to a blow mold, where air forces the
glass into the final shape.
Secondary processing
Part of the
production process in which some
types of glass are subjected to second-
ary processing such as
annealing
, which
involves controlled cooling processes
intended to prevent cracking;
tempering
,
which involves uniform reheating and
rapid cooling to induce tension in the
glass; and
coating
, which involves physi-
cal and chemical processes that change
optical qualities, enable scratch resist-
ance, or increase strength.
Decorating
processes involve material removal
(physically or chemically), adding material
(low temperature glass, metal, or enamel
coatings, films, or printing), and
post-
forming
, which involves selective
reheating and manipulation of forms
and surfaces.
1.
Molten glass
dropped into
blank mold
2.
Plunger
presses
blank shape
3.
Blank
pressed
4.
Blank
shaped
5.
Blank
transferred
to blow
mold
6.
Final
shape
blown
PRESS AND BLOW
Job on:93996
Scn :
#
175 Si
Dept : DTP D/
2
Job on:93996 CTP Title : RP_Process Material Measurements Client : Pro_Vision
Scn :
#
175 Size : 146.05(w) 209.55(h)mm _M2_Mac D
Dept : DTP D/O : 16.12.05 (Job on:000000 D/O : 00.00.01 Co: CM0)
Pantone
109 U
p72
93996_PM&M_066-129_M2.qxd5 16/12/05 12:43 PM Page 72

Get Process, Materials, and Measurements now with the O’Reilly learning platform.

O’Reilly members experience live online training, plus books, videos, and digital content from nearly 200 publishers.