Hot Rolled Steel Strip - Hoesch Hohenlimburg

Hot Rolled Steel Strip
Company of
ThyssenKrupp
Steel Hoesch Hohenlimburg
TK

2
Hohenlimburg hot-rolled
narrow steel strip
Hohenlimburg narrow steel
strip is produced by hot-rolling
from slabs and available in
widths up to 700 mm and in
thicknesses from 1.5 to 16 mm.
Hohenlimburg narrow steel
strip is available with mill
edges, with cut edges slit from
multiple widths, or with trimmed
edges.
It can be supplied in coils weighing
up to 20 kgs/mm strip
width or in bars from 1 to 18 m
in length, pickled, non-pickled,
or heat-treated.
Hohenlimburg narrow steel
strip represents the sum of our
more than 100 years of experience
in steel production and
processing. Our narrow-strip
mill has been continuous
modernized over the years and
is now completely processautomated.
There is no
question that it offers the best
prerequisites for achieving
superior tolerances and technological
properties ongoing.
Hohenlimburg narrow steel
strip signifies:
• Extremely tight thickness
tolerances
• Optimum symmetric thickness
in profile
• Superior surface quality
• Uniform material properties
• Application-specific microstructures
• Optimum shaping properties
including in higherstrength
steels
• Customized batch sizes
Hohenlimburg narrow steel
strip will not only maintain its
qualitative superiority but will
enhance it even further. To
achieve this ambitious goal,
we are making considerable
investments. Our plant and
machinery is state-of-the-art
and guarantees the impressive
product advantages our
Hohenlimburg narrow steel
strip is famous for.
Hohenlimburg narrow steel
strip is used in nearly all branches
of industry.
As a result of our ongoing
research and development of
our product quality, and based
on our long-standing experience
from listening to our customer´s
needs and requests, we
can now offer a solution to any
problem our customers may
come up with.
You will find our technical application
consultants able to
assist you in your specific
application.
Please contact us.
Hubbalkenofen Walking beam Reversier-Vorstraße
Reversing
furnace
roughing mill
Walking beam furnace
The walking beam furnace
offers optimum prerequisites
for
• Homogenous soaking of
the rolling stock from all
sides.
• High flexibility of the heating
process by eleven
independent temperature
control zones.
• A process-controlled
time/temperature profile
optimally adapted to the
respective material during
the heating-up process.
Reversing roughing mill
The high-capacity universal
reversing mill equipped with
hydraulic gauge and width control
system consists of a horizontal
2-high stand with a flanged-on
edger in front and fully
automatically rolls slabs of a
wide variety of sizes into intermediate
strips.
This means:
• Microstructures with
homogenous density are
achieved by high reduction
ratios.
• Highly effective descaling
assures optimum rough
strip surfaces.
• Computer-controlled rolling
produces geometrically
optimized intermediate
strips.

Narrow steel strip mill
Technical description
Thermal Wärmehauben tunnel Finishing Fertigstraße train Measuring
house
Kühlstrecke Cooling section Haspelanlage
Downcoiler
Thermal tunnel
The thermal tunnel with its
highly effective heat insulation
is configurated to assure that:
• The temperature is rehomogenized
throughout
the cross section profile
(avoidance of edge cooling).
• The essential final rolling
temperature is maintained
at a constant level over the
entire strip length even in
coils with very high specific
weights.
Finishing train
The finishing train consisting
of two 2-high and seven 4-high
stands is equipped with a
high-tech process automation
system developed by ourselves
and offering the following
advantages:
• Extremely narrow thickness
tolerances even at the strip
head of the first coil following
a size/quality change.
• Selective control of strip
camber and flatness by
load distribution strategies
and roll bending.
• Maintaining the specifically
required final rolling temperatures
within narrow limits.
This process is assisted by
an integrated ”speed-up
system“.
The process-automated edgers
installed in front and behind
the 2-high stands are instrumental
in assuring extremely
narrow tolerances in the
finished strip width.
Cooling section
The laminar cooling section
based on specific cooling strategies
and advanced process
automation using neuronal networks
allows:
• Targeted setting of specified
microstructure conditions.
• Achievement of mechanical-technological
properties
with very tight tolerances.
Coiler group
The computer-controlled
coiler group with its base
construction and the possibility,
to adapt the coiling parameter
settings to the various materials,
provides:
• Tight, straight-edged coiling
and, thereby
• the right conditions for processing
without mechanical
damage.
An automatic strapping machine
ties up the coils in the coiling
cellar directly behind the downcoiler
(in longitudinal direction).

4 Production equipment
View into the walking beam furnace
Reversing roughing stand
Thermal tunnel (open) Cooling section
Coiler below floor level
Finishing train

Total view of the pickling line
Parsytec surface spray-pickling system
Total view of slitting line III
Our production is based on
DIN EN 10048/DIN EN 10051
for hot-rolled strip (depending
on the rolling width) and on
DIN 59200 for wide flat steel.
Upon request, we can also
produce to other domestic or
foreign standards. Process
automation allows thickness
tolerances similar to those
applicable for cold-rolled strip.
The cut-to-length lines are
capable of maintaining very
narrow length tolerances for
hot-rolled strip in bars and
plate steel.
Surface conditions with well
picklable homogenous surface
pickled (dry)
pickled and oiled.
A wide range of microstructures
can be produced directly
via the rolling heat.
Additional heat treatments:
• Stress-relief annealing
• Soft annealing
• Spheroidizing on globular
cementite
• Chloric-acid pickling lines
for all cross sections and
qualities produced (continuous
pickling line and
push-pull pickling line).
• Slitting lines (up to cuttingto-length
line including
12 mm thickness).
Tolerances
Surface conditions
Heat treatments
Additional processing
5

6
Mild unalloyed steels and general structural steels
Mild unalloyed steels are delivered
to ENDIN 1614, part 1,
for cold rolling and to DINEN
10111 for direct cold forming
(direct processing of the hotrolled
strip). General structural
steels are standardized to
DIN EN 10025, but are also
available as pre-material for
other products, e.g. steel pipes
for long-distance pipelines, for
flammable liquids and gases to
DIN EN 10208.
Apart from standardized qualities,
we are offering numerous
special qualities optimal adapted
to their intended final use.
In the case of mild unalloyed
steels for direct processing we
have developed special qualities
in addition to grades
DD11, DD12, DD13 to DINEN
10111. For instance, a very
soft quality (now DD14) with
yield points otherwise only
achieved by cold strip, and one
quality with a somewhat higher
tensile strength but still excellent
cold-formability.
Mild unalloyed steels (DINEN 10111:1998)
To replace the no longer produceable
rimming steels, we have
developed a vacuum-killed
deep-drawing quality for casehardening.
This steel contains
only small traces of aluminum
and can (in most cases) be
case-hardened like rimming
steel.
For the deep drawing of shells
and similar structural components
we supply steels with
very low earing characteristics.
That applies for direct processing
as well as after a cold rolling
process. The chemical
composition and the production
parameters are tailored to specifications.
By suitable temperature control
we can produce hot-rolled strip
with a carbon content of less
than 0.20%, with a uniform
fine microstructure suitable for
fine blanking without prior heat
treatment.
Designation Designation Special features
(according to (according to
DINEN 10111) DIN 1614, part 2)
By special rolling processes
and suitable temperature control
we can produce hot-rolled
strip for the production of RP
cold strip surfaces.
General structural steels up to
S 355 with good cold-formability
(chamfering, roll profiling)
can be produced by using a
very low sulphur content and
other measures during steel
production.
In view of their good cold-formability,
we recommend microalloyed
fine grain structural
steels for applications demanding
high yield points and tensile
strengths.
DD14 StW 24 W *) Best cold-formability
DD13 StW 24 Very good cold-formability
DD12 StW 23 Good cold-formability
DD11 StW 22 Basic grade
Increased minimum yield point
— StW 24 H **) and special microstructur to achieve
high endurance values
*) Hoesch special quality **) Hoesch special quality (increased carbon content compared to StW 24)

Control arm, 2.75mm thick
Shock absorber support,
2.0mm thick
Gear part, monobloc design,
6.5mm thick
Brake piston,
6.0mm thick
Examples of application
Support with outside fins,
4.0mm thick
Brake support plate,
2.25mm thick
Claw for alternator,
10.5mm thick
Trailing arm,
2.5mm thick
7

8 Micro-alloyed low-perlitic fine-grain steels
Nomenclature
These fine-grain steels are fully
killed micro-alloyed steels with
low carbon equivalents. Due to
their chemical composition and
fine-grain microstructure achieved
by thermo-mechanical treatment,
these steels have high
yield points and very good
cold-formability. An even higher
degree of cold-formability
can be achieved by a very low
sulphur content or "sulphide
control", i.e. fixation of the sulphur
to avoid the formation of
undesirable manganese sulphides.
The precisely controlled
production on our hot strip mill
is realized by precise setting of
the rolling temperatures and
reduction rates as well as by
controlled cooling rates and
reel temperatures after rolling.
*) Acc. to the Stahl-Eisen-Liste, 1990 Edition
Our production program includes
N grades which are also
rolled under controlled conditions.
Analysis and temperature
are selected to permit subsequent
normalizing under
specified conditions.
For further details, see our
special brochure.
Hot-rolled fine-grain structural
steels are particularly suitable
for direct processing with high
requirements on cold-formability.
This is much more advantageous
than with conventional
structural steels because of the
chemical composition and
microstructure. HSM steels
(Hoesch special structural
steels, micro-alloyed) can be
bent with small radii and rolled
into profiles. They can also be
deep-drawn and stretch-formed,
with certain restrictions
in the case of the harder qualities.
These fine-grain steels offer
the engineer good cold-formability
and high yield strengths
at the same time. With other
steels, similar properties can
only be achieved by heat treatment
of the component. The
low-carbon, manganese, and
micro-alloy contents create a
low carbon equivalent and therefore
ensure good weldability.
Only qualities with minimum
yield points of 600 N/mm 2 and
above, and the N grades can
reach a carbon equivalent
comparable to structural steel
of S 355 (DIN EN 10025).
Further details, in particular
with regard to chemical composition
and mechanical properties,
including several potential
applications, are described in
our special brochure.
Hoesch designation Material No. Designation in Designation to
Stahl-Eisen-Werkstoff- DIN EN 10 149/2,
blatt 092-90 1995
HSM 260 1.0970* (Q St E 260 TM*) –
HSM 300 1.0972* (Q St E 300 TM*) S 315 MC
HSM 340 1.0974 Q St E 340 TM –
– 1.0976 – S 355 MC
HSM 380 1.0978 Q St E 380 TM –
HSM 420 1.0980 Q St E 420 TM S 420 MC
HSM 460 1.0982 Q St E 460 TM S 460 MC
HSM 500 1.0984 Q St E 500 TM S 500 MC
HSM 550 1.0986 Q St E 550 TM S 550 MC
HSM 600 1.8969 (Q St E 600 TM*) S 600 MC
HSM 650 1.8976 (Q St E 650 TM*) S 650 MC
HSM 700 1.8974 (Q St E 690 TM*) S 700 MC
HSM 760 Special Hoesch quality

Seat belt retractor cage,
1.75 – 3.5mm thick
Truck side members,
4.0 – 12.0mm thick
Gear component,
1 st stage
Gear component,
2 nd stage
Gear component,
3 rd stage
Gear component,
4 sth stage
Gear component,
5 th stage
4.85mm thick
Cold-rolled profile for railway wagons,
HSM 700, 2.0mm thick
Examples of application
Car seat slide rails, 2.0mm thick
Hot-rolles components for car jacks,
2.0 – 4.0mm thick
Steering column, various thickesses
Carrier plate,
8.2 mm thick
9
Ball pressure reservoir,
3.5 – 6.5mm thick
Rear axle carrier,
6.0mm thick
Car lock, various parts
from hot strip

10 Case-hardening and heat-treatable steels
Annealing shop
These are primarily steels acc
to DIN EN 10083 and DIN
10084 but also nitriding steels
(DIN EN 10085), steels for
flame and induction hardening
(DIN EN 10086), numerous tool
steels to DIN EN ISO 4957, and
hot-rolled strip for heat-treata-
ble springs (DIN EN 10089) as
well as for cold-rolled strip steel
for springs (DIN EN 10 132-4).
Furthermore, we supply various
special qualities, e.g. hot-rolled
strip for welded gas bottles
(DIN EN 10 120) and for deep
drawn and/or stretch-reduced
gas bottles, hot-rolled strip for
cold-rolled tape rules, hot-rolled
strip for razorblade steel, etc.
The production of these steels
is optimally tailored to the
customer´s intended use. This
is valid for the chemical analysis,
the hot-strip production
parameters, and any subsequent
heat treatment.
A fine, predominantly sorbitic
microstructure has proven its
worth in the cold-rolling of
case-hardening and heattreatable
steels. This permits
to cold-roll without prior heat
treatment. For instance, quality
C75 steel can be cold-rolled
with a reduction of up to 60%,
depending on the capabilities
of the cold rolling mill. Steels
with a predominantly sorbitic
microstructure offer advantages
in hardening or heat
treatment: shorter austenization
times, lower hardening
temperatures, more consistent
properties.
Cold strip (-LG) with lower yield
points and strength values may
require a less fine sorbitic
microstructure in the hot strip.
In-depth discussions swith the
customer are recommended to
optimize the product for its
intended use, taking into
account the available production
equipment.
The direct processing of hotrolled
strip requires a special
heat-treated condition. This
applies especially to fine blanking.
While a fine as-rolled
microstructure is usually optimal
for case hardening steels
with a low carbon content, an
annealed microstructure of
spheroidal cementite is suitable
for fine blanking of hot-rolled
strip with higher carbon contents.
It is important to choose the
correct chemical composition
for deep drawing carbon steels.
A very low sulphur content is
especially important, often also
a low silicium content. Further
processing by cold-rolling
should start with a fine sorbitic
hot-strip microstructure. If hot
strip is directly processed, the
optimal delivery condition will
depend on the production processes
available at the customer´s
works. We would be pleased
to advise you in this
respect as well.
As a precaution against the risk
of graphite precipitation and to
optimize heat treatment properties,
we recommend the lowest
possible aluminum content and
a chromium content of approx.
0.20%. Experience has shown
that this chromium content is
not detrimental to further processing.
However, if an aluminum-killed
fine-grain steel is
required, or if - in rare cases -
the chromium content is not
desired, the processing parameters
may have to be set
accordingly.
Soft annealed microstructure consisting
of spheroidal cementite in ferrite,
quality C60 (magnification x 500).
Sorbitic microstructure of a hot-rolled
strip, quality C60 (magnification x 500).

Steel bottle, 5.5mm thick
Clutch diaphragm spring, 3.5mm thick
Clamping sleeve,
5.0mm thick
Hole plate as turntable for expanding reel, 8.0mm thick
Examples of application
Safety belt adjuster,
2.2mm thick
Cutter knife,
8.0mm thick
Clutch discs, 5.0 – 8.5mm thick
Gear shift forks,
6.0mm thick
11

12 Hot-rolled boron-alloyed
Case-hardening and heat-treatable steels
Passenger car rear axle carrier
thickness 2.75mm
We are continuously working
on the development of special
steel grades some of which
have already been described in
the previous chapters. Another
example are our boron-alloyed
steels (DIN EN 10083-3 and
special steel grades, see table
below).
Hot-rolled boron-alloyed steels
with medium carbon contents
are particularly suited for applications
where moderately high
strengths and, therefore, still
quite good cold-formability in
the as-rolled condition are
required, although high hardness
values are nevertheless
expected after hardening.
These steels can be quenched
either in water or in oil. Tempering
after hardening can generally
be omitted because of the
very high tenacity of the material.
In special cases, tempering
at very low temperatures
(180°C max) may be advisable.
Boron steels have proven their
worth especially in agricultural
machinery, where they have
primarily replaced silicium-
alloyed steels (38 Si 7m 55 Si
7). One of their advantages
over Si steels is low sensitivity
to decarburization during heat
treatment.
A wide variety of other applications
rely on boron steels
because of the above advantages
for rational production processes.
Apart from boron-alloyed steels
which are used instead of heattreating
steels, we can supply a
boron-alloyed case-hardening
steel (Hoesch brand HLB 8)
which stands out by the high
strength and ductility values in
its uncarborized core area.
For further information, please
see our brochure "Hot-rolled
boron-alloyed case hardening
and heat-treatable steels".
Hoesch designation Steel grade Designation to Standard of quality
DIN EN 10027-1 *) DIN EN 10027-1 *) DIN EN 10083-3
HLB 8 8MnCrB3 1.7135 –
HLB 17 17MnB3 1.5506 –
HLB 22 22MnB5 1.5528 20MnB5 **)
HLB 27 27MnCrB5-2 1.7182 27MnCrB5-2
HLB 30 30MnB5 1.5531 30MnB5
HLB 37 37MnB4 1.5524 38MnB5 **)
HLB 42 40MnB4 1.5527 39MnCrB6-2 **)
HLB 44 – – –
*) acc. to Stahl-Eisen-Liste
**) Minor deviations for single elements. All grades according to DIN EN 10083-3
are available upon request.
Fixing angle, 3.0mm thick
Fastening angle, 4.0mm thick
Chain link, 2.5mm thick

Temperature control and documentation
13

14
Strip thickness (mm)
Strip thickness (mm)
16
14
12
10
8
6
4
2
16
14
12
10
8
6
4
2
Available sizes:
Rolling and pickling program
100 200 300 400 500 600 685
Strip thickness (mm)
100 200 300 400 500 600 685
Strip thickness (mm)
Strips with a tensile strength ≤ 450 N/mm 2
Strips with a tensile strength > 450 ≤ 650 N/mm 2
Strips with a tensile strength > 650 ≤ 800 N/mm 2
Strips with a tensile strength > 800 N/mm 2 (≤ 1200 N/mm 2 )
The tensile strength values refer to the (cold) as-rolled condition. For some grades, e.g. micro-alloyed
fine-grain steels or high-carbonized and alloyed steels, the limit values will vary slightly.
Please contact our Technical Customer Consulting Dept.
Widths: 25 – 685mm
Max. thicknesses: 16 mm
(strip thicknesses < 1.5 mm by
agreement)
Edge condition:
As rolled edges (ME)
Trimmed edges
Strip thickness (mm)
Strip thickness (mm)
16
14
12
10
8
6
4
2
16
14
12
10
8
6
4
2
100 200 300 400 500 600 685
Strip thickness (mm)
100 200 300 400 500 600 685
Strip thickness (mm)
Inner coil diamter:
approx. 500mm
(optionally up to 610 mm)
Coil weight:
by agreement
Steel strip in cut lengths:
Widths: 25 – 660 mm
Lengths: 1,000 – 18,000 mm

Mild unalloyed steels
General structural steels
Quality and stainless
structural steels
Special structure
steels
Tool steels
Other steels
Special materials*
Heat-resistant
materials*
Corrosion-resistant
steels*
Materials
Material
DIN-
Standard
EN-
Standard
Mat.
list
Euro
Standard
Mild unalloyed steel for cold-rolling 1614, Part 1
Mild unalloyed steel for direct cold forming
(direct processing of hot strip) 1614, Part 2 EN 10111 111-77
17100 EN 10025 025-72
Quenched and tempered steels 17200 EN 10083 083-70
Case-hardenable steels 17210 EN 10084 084-70
Nitriding steels 17211 EN 10085 085-70
Steels for flame and induction hardening 17212 EN 10086 086-70
Hot-rolled strip for hardenable springs 17221 EN 10089 089-71
Hot-rolled strip for cold-rolled steel strips for springs 17222 EN 10132-4 132-79
Free cutting steels 1651 EN 10087 087-70
Hot-rolled strip for welded gasbottles EN 10120 120-83
Cold-upsetting and cold-extruding steels 1654 EN 10263 119-74
Temperature-resistant steel plate and strip 17155 EN 10028-2 028-85
Hot-rolled strip for steel pipes for pipelines
for flammable liquids, gases 17172 EN 10208
Hot-rolled strip for heat-resistant steel pipes 17177 EN 10217-2
Compresses-hydrogen-resistant steels 590-61
Cold ductile steels 17280 EN 10028-4 129-76
Ship building steels To the guidelines of the
classification company
Hardenable steels with special analyses To special specifications
Sulphide-controlled molten steels To special specifications
Carbon steels for deep-drawable cold strip To special specifications
Hot-rolled strip for deep-drawable cold-rolled spring steels To special specifications
Micro-alloyed fine-grain steels for cold-forming (HSM-qualities) EN 10149 092-90 149-80
Weather-resistant structural steels (Resista steels) EN 10155 087-81 155-80
Boron-alloyed case-hardened and quenched and tempered steels (HLB Qualities) 10083-3
unalloyed tool steels 17350 EN ISO 4957 096-79
alloyed cold-working steels 17350 EN ISO 4957 096-79
alloyed hot-working steels 17350 EN ISO 4957 096-79
Antifriction bearing steels 17230 EN ISO 683-17 094-73
Soft magnetic steels for direct current relays 17405
Heat-resistant alloys and various
non-ferrous metals and their alloys To various specifications
Iron alloys with special thermal elongation 385-57
Non-magnetizeable steels 390-61
High-strength martensitic hardening steels To various specifications
Heat transfer alloys 17470
Heat-resistant rolling and forging steels EN 10095 470-76
Stainless steels 17440 EN 10088 400-88 088-86
Hot-rolled strip for stainless steel springs 17224 EN 10151
*These special alloys are rolled by Hoesch Hohenlimburg under subcontract
15

Hoesch Hohenlimburg GmbH
Narrow Steel Strip Division
Oeger Strasse 120
D-58119 Hagen
Tel.: +49 (2334) 9123 91 or 91-0
Fax: +49 (2334) 9133 69
Technical Customer Consulting Department:
Tel.: +49 (2334) 913253/2271/2295
Fax: +49 (2334) 9133 58
E-Mail: mittelband@hho.thyssenkrupp.com
Internet: www.hoesch-hohenlimburg.de
Ausgabe 2002 · Edition 2002 · Edition 2002