Non-stop production of Heineken export cans in south Holland
Every day and all day long a steady stream
of trucks delivers tin plate sheet by the ton
to a factory at Oss in southern Holland.
And as they offload, even more trucks
leave the factory in an equally constant
flow, carrying consignments of tin cans in
a variety of brightly coloured commercial
liveries to all parts of the Benelux
countries.
The cans serve a host of packaging pur
poses. There are cans for packing meat,
milk powder, soup, pet food; cans with
lids for paints, oils and greases; and of
course cans for beverages, of which a
large percentage - some 120 million a year
- go to Heineken to be filled with beer.
Thomassen Drijver - Verblifa N.V.
(TDV), established some 60 years ago at
Deventer, East Holland, is today the lar
gest packing industry in the Benelux
countries. For the past ten years it has for
med part of the Continental Can
Company, New York.
The two-piece type of can TDV produces
for beverage manufacture comprises a
small tin tube with separate aluminium lid
incorporating a ring-pull opener. It is
comparatively new, having entered pro
duction in 1971but has quickly achieved
popularity.
Coiled metal
Supplies of tin plate for can manufacture
come mainly from Dutch steel mills at the
port of IJmuiden west of Amsterdam. The
metal leaves the mills in huge coils, each
weighing between eight and 10 tons,
which are cut into sheets at other plants be
fore reaching Oss.
The quantities handled by this single unit
in Europe's metal packaging industries
give an indication scale of the modem
beverage suppliers. Each tmck bringing
tin plate carries some 12000 sheets of the
metal, a product of two of the original
coilsEach sheet provides enough metal for
42 cans, so that two stillages containing
3000 sheets represents a total of 126,000
cans or one truckload of the finished pro-
6
duct.
To cope with the required output Oss oper
ates three shifts covering 24 hours daily
throughout the working week. Four pro
duction lines are devoted to two-piece
cans.
Draw and ironing process
Heineken can manufacture begins with the
tin plate sheets being stamped into 42 flat
circles of metal which are then formed in
to a kind of wide, shallow cup. the second
drawing operation reduces the diameter of
the cup and raises the circular "wall" to
about half its finished height. In the iron
ing press the punch transforms the embry
onic can into tube configuration, the cir
cular wall now only 0.1 mm thick, the bot
tom - convex inside - rather more robust at
0.3 mm. Another machine cuts the tube to
precise can height and the container is al
most ready for paintwork. But first it has
to be degreased, for during the 'cupping'
and "wall-ironing" that have brought it to
its present shape it has been covered in a
lubricant.
After degreasing by a special solvent the
cans are ready for the first stage of paint
ing - the application of a \yhite base coat
by a base coating machine. There are four
such machines, one for each production
line, and each covers the outsides of cans
between 800 and 900 a minute. But before
coating begins the cans move forward to
form a pool of identical containers which
can be routed to any of the coaters. This
mass-handling phase is a relatively new
production technique in which TDV was
the first company to experiment. It invol
ves the use of-wider conveyors travelling
at lower speeds. The reduced flow rate is
"kinder" to the cans and also facilitates
switching the direction of the conveyor
when necessary. The slowly moving pool
of cans resembles nothing so much as a
well-behaved crowd on its way perhaps to
a football match. Their assembly in this
docile concourse facilitates their being fed
to any of the four coaters - a degree of flex
ibility that pays off on occasions such as,
for example, the temporary suspension of
a machine for servicing on re-charging
with lacquer. In this case the cans headed
off from the closed outlet can be seen shuf
fling back to other routes still accepting
candidates for lacquer treatment. The
overall visual effect of streams of cans
constantly leaving the central reservoir
has given rise to the aptly descriptive term
- the "sponge" system.
Industrial miracle
From this point on the visitor becomes
more and more aware of witnessing one of
those marvels of modern automation de
veloped in the service of the consumer in
dustries, an industrial miracle that rapidly
transforms flat tin plate sheet into thou
sands of finished cans in their various
brand colour schemes.
The dominant impression that lingers in
the mind is of cans being conveyed in all
directions, horizontally, vertically, in
curved diagonals, turning corners, pas
sing overhead, a multi-stream cavalcade,
an organized chaos that when viewed with
the protection of earplugs (supplied at the
start of the tour) has an eerie, silent film
quality but which, for the curious visitor
who listens momentarily, reveals itself as
being accompanied by the jostling clatter
of metal on metal and the clangour of pro
duction machinery.
A quick double-take. Surely those Heine
ken cans passing overhead are hanging up
side down on the lower belt of a conveyor!
And those climbing vertically are sticking
straight out from the conveyor belts with
out visible means of support! How is it
Tin plate sheet into
beverage containers
Tin plate.to Heineken can!
Continued on page 9
