Advanced equipment for
the aluminium industry
INGOT CASTING PLANT
Hertwich Engineering:
leading technology in the aluminium casthouse
New Ingot Casting Plant
Freezing and cooling of ingots exclusively by air
Automatic strapping
Bundles ready for shipping
Considerably extended service life of moulds due to absence of water
(no thermal shock)
No hazard of explosions caused by water
No costs for provision of water and related infrastructure
Much reduced maintenance costs due to absence of water and vapour
(corrosion, wear and tear)
No absorption of hydrogen by the hot metal
Avoiding penetration of water into shrinkholes and pores
Fully automated integrated production cycle
Strapping system designed for plastic or metal (Aluminium or steel)
strapping, which can be applied alternatively
Automatic application of cross strapping
HERTWICH ENGINEERING
Weinbergerstrasse 6
A-5280 BRAUNAU
AUSTRIA
Phone: +43 7722 806-0
Fax:
+43 7722 806-122
E-mail: [email protected]
Internet: www.hertwich.com
INGOT CASTING, ENTIRELY WITHOUT WATER
Innovative open mould ingot casting line, using air only for freezing and cooling of the metal
The
technical
requirements
to
tenderers by AUSTRIA SEKUNDÄR
ALUMINIUM (ASA), were rather
stringent: To deliver a highly efficient
plant of compact design, fully
automated from metal inlet to finished
product (ingot stacks ready for
shipment), yet without using any water
for cooling.
A real challenge, well to the taste of
HERTWICH ENGINEERING (HE),
who have to date built a number of
ingot casters, all of which are based
on the horizontal direct chill (HDC)
process. The open ingot caster project
came as a welcome novelty.
Additional stimulation was ensured by
ASA’s requirement for minimum
production
interruption
between
removal of the old casting conveyor,
which was still in operation, and
completion of the new plant.
Project Preparation and Execution
First things first, HE started the job by
working out the essential basics: Ingot
geometry and mould design were
optimised in the own R&D facility,
followed by cooling tests on ingots in
an air stream; thereby the necessary
air velocities and times were
established.
Construction of the plant was carried
out under vivid exchange of ideas with
experts from ASA. Demolishing of the
old plant, foundation work and
installation of the new plant were
completed on schedule within 5
weeks, working double shift.
The ensuing weeks were critical to
both parties: To HE this meant the
commissioning of a complex prototype
plant, while to ASA it was the
resumption of production to comply
with existing delivery commitments.
Fig. 1: Ingot casting line with air cooling
Both targets were indeed met due
to much mutual consideration,
strong nerves and a pinch of luck.
As for plant operation, optimising
of the complex restart routines, as
well as the extensive data and
monitoring technology took a little
longer, but did not unduly impair
production.
The plant today represents a
reliable production tool, with
expectations by ASA experts in the
waterless caster well satisfied.
Advantages of an air cooled
ingot caster:
☺ Moulds are not subjected to
temperature shock, as there is no
cooling water to get into contact
with the hot moulds. This results in
extended service life of moulds of
several years. Water cooled
moulds usually last only one year.
☺ The water explosion hazard, which
is common with water cooled casting
conveyors due to cracks or moisture
condensation, is altogether avoided.
☺ No cooling water consumption, and
consequently no need for cooling
water infrastructure like basins and
cooling towers with all inherent
problems like water treatment, fouling
and algae.
☺ The extent of maintenance is
reduced thanks to the moulds not
being exposed to water and steam.
Chains of the casting conveyor may
be equipped with sealed-for-life type
roller bearings, which ensure smooth
and troublefree operation.
HERTWICH ENGINEERING GmbH, Braunau – Austria
Date: 28.12.2001
☺ Warm air may be used for heating
the building during winter, and may be
ducted through the roof during
summer.
☺ Water cooled casting conveyors
have to be arranged in one plane due
to the water basin, into which moulds
are required to dip. With air cooled
conveyors the transport plane can be
raised only meters after the casting
area, thereby running the bigger part
of the conveyor above ground. As a
result extensive, costly foundation
work can be saved.
Production
Design production of the plant is
8.000 kg/h, ingot weight is 8 kg.
With larger (and heavier) ingots
production up to 15.000 kg/h can
be achieved.
☺ Several additional advantages are
apparent due to ingots being further
air cooled to ambient temperature
(after being ejected from their
moulds):
which also serves as ingot storage
(patent applied). Ingots coming from
the
casting
conveyor
are
accumulated
into
layers
and
introduced into the cooling tower in
cycles.
The
paternoster
type
transport system moves the ingot
layer upward. At the uppermost
position a layer is transferred to the
descending part of the transport
system, and is then lowered in
cycles. Several light axial type
ventilators induce a horizontal
cooling air flow which passes
between the layers thereby cooling
the ingots. Once the ingots have
reached the last (lowest) position
their temperature measures only a
few degrees above ambient. From
the cooling tower Ingot layers are
transferred to the stacker. The new
cooling tower has proven to
performed reliably with very little
maintenance.
b) Stacking
Cross stacking of ingot layers is onto
pallets or footing ingots. Single or
double stacks can be assembled.
Fig 2: Plant layout
☺ Any penetration of water into pores
or shrinkage cavities can be ruled
out.
☺ Hydrogen pick-up by liquid metal is
not possible.
☺ Much
reduced
maintenance
downstream
of
the
casting
conveyor too, and with it extended
service life of the equipment, due
to the absence of water and
steam.
SPECIAL TECHNICAL
FEATURES
a) Cooling of ejected ingots
After leaving the conveyor, ingots
are still at a temperature of 400
to 450 °C. However, for further
handling the ingots need to be
cooled down to near ambient
temperature. This is particularly
important for ink jet marking,
strapping and labelling. Since air
cooling takes substantially longer
than water cooling, a special
cooling tower was developed,
Fig. 3: Principle of cooling tower
a...inlet and outlet conveyor
b...upward conveyor,
c...transverse layer transfer
d...downward conveyor
e... axial fan
Ingot casting, entirely without water
Page 2 of 3
HERTWICH ENGINEERING GmbH, Braunau – Austria
Date: 28.12.2001
c) Marking
Two separate ink jet marking
units are employed for marking
each ingot as well as each ingot
layer (the outermost ingot of
each
layer).
The
printed
information includes alloy code,
cast number etc.
special
monitoring
and
diagnosis program. In the rare
case of a departure from
normal operation, the unit
reacts at once by generating an
error message with information
about the possible cause of
error and proposals for solving
the problem.
d) Strapping of ingot stacks
The automatic strapping system is
designed to allow strapping
alternatively with metal band (steel
or aluminium) or PET band, at any
time.
Strapping
includes
alternatively footing ingots or
pallets. The additional cross
strapping
operation
provides
essential stability to the stack.
Cross strapping can also be used
for joining two stacks into a double
stack.
e) Colour Coding
Stacks can be marked on the side
with a three colour code, using
crosses or vertical colour stripes.
f)
Automation
A high level of automation can be
taken for granted in HE equipment.
Each
individual
operational
sequence is supervised by a
After each interruption of
normal operation the plant is
restored to normal working
condition by special restart
programs.
No
manual
commands
are
needed
therefore. The restart programs
alone return all parts of the
plant involved to their defined
starting position.
Since there is no manual
intervention in the control
mechanism during restarting,
potential human error is
avoided.
This
contributes
decisively to the very reliable
operation of the plant. The unit
is controlled by a Simatic S7300 system interfaced with an
industrial PC, which processes
the menu and recipe systems
and operates the peripheral
equipment, alarm systems and
various other functions.
In accordance with other data
input from a host computer, up to
three different orders can be
processed in one batch. The
parameters to be set individually
for each order are:
Inkjet ingot marking (batch
number,
alloy
code,
customer's name)
Stack type (single / double)
Stack weight (number of
layers)
Base (Ingots or pallet)
Colour code (colour choice,
from i.e. cross or stripes)
Design and printing of the
weighing label
Strapping pattern (number of
strips)
Strap type (plastic or metal).
Final Assessment
All in all, the Ingot casting line
installed at ASA has shown that
even with conventional, already
long known types of equipment it
is still possible to make essential
innovations to the benefit of the
operator.
Fig. 5: Ingot stacks ready for dispatch
Fig 4: Stack types
Ingot casting, entirely without water
Page 3 of 3
Ingot casting belt with air type cooling system
Liquid metal pouring system
Ingot casting belt with air type cooling system
Ingot stack exit
Ingot casting belt with air type cooling system
Ingot stacks
LIEFERPROGRAMM
PRODUCT RANGE
•
Durchlaufhomogenisierungsanlage
Kapazität: 1.000 kg/h – 23.000 kg/h
•
Continuous Homogenizing Plant
Capacity: 1.000 kg/h – 23.000 kg/h
•
Kammerhomogenisierungsofen
•
Batch Homogenizing Furnace
•
Ultraschall Prüfeinrichtung
a) Kernrisse und Einschlüsse
b) für 100 % Prüfung: Multi Kopf System
•
Ultrasonic Testing Equipment
a) Centre cracks and random inclusions
b) For 100 % testing: multi head system
•
Säge- und Verpackungsanlagen,
Stapel- und Transportmaschinen
•
Sawing and Packing Plants,
Stackers and Handling Equipment
•
Brikettierpresse
•
Briquetting Press
•
Horizontale und Vertikale StranggießAnlage für Rundbarren, Stromschienen,
T-Bars, Massel und Walzbarren
•
Horizontal and Vertical Casting Plant for
Billet, Busbar, T-Bar, Foundry Ingot and
Rolling Ingot
•
Kompakt Umschmelzanlage
Kapazität: 4.000 – 30.000 T/Jahr
•
Compact Type Remelt Plant
Capacity: 4.000 – 30.000 tpy
•
Chargiermaschinen
•
Charging Machines
•
Schmelzeentgasungseinheiten
•
Inline Degassing Units
•
Spezialmaschinen
•
Customized Machinery
NEU:
• Schmelz- und Gießöfen der neuesten
Technologie, für beschichtete Schrotte etc.
Schmelzleistung:1.000 – 10.000 kg/h
NEW:
• Melting and Casting Furnaces of
Advanced Technology for
contaminated scrap etc.
Melting Capacity: 1.000 – 10.000 kg/hour
•
Dreh-Kippofen, URTF 3 – 14
Universell einsetzbar + Alurec ®
•
Rotary Tilting Furnace, URTF 3 – 14
“The Universal Furnace + Alurec ®
•
Horizontalstranggießanlagen für
Schmiede- und SSM Barren und
Magnesium Massel
Durchmesser 25 bis 150 mm
•
Horizontal DC Casting Plants for
Forging, SSM Feedstock and
Magnesium-Ingot
Diameter range 1” – 6”
•
Masselgießband
!Kühlung ausschließlich mit Luft!
•
Ingot Casting Belt
!Cooling exclusively with air!
•
Elektromagnetische Pumpen und Rührer
•
Electromagnetic Pumps and Stirrers
•
Vorrichtung zum Einschmelzen von
Spänen
•
Facilities for Remelting of Swarf
HERTWICH ENGINEERING
Weinbergerstrasse 6
A 5280 BRAUNAU – AUSTRIA
Phone : +43 (0) 7722 / 806-0
Fax :
+43 (0) 7722 / 806-122
E-mail : [email protected]
Internet : www.hertwich.com