Process, Materials, and Measurements

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