Hardened and
tempered steel strip
Down! Come! Fetch! And Down again!
What has our hardened and tempered steel strip
got to do with dog commands?
If you have a dog that is very active you might appreciate a retractable dog leash, which
gives your dog the greatest possible freedom of movement without it feeling restricted
from a leash. Hardened and tempered steel strip produced by C.D. Wälzholz ensures
a smooth and long lasting mechanism. Many of our customers’ products using materials
made by CDW cannot be detected at first glance – just like this retractable dog leash.
But one thing is certain: you will realise our quality immediately.
Our hardened and tempered steel strip has proved itself in daily practice for many years.
Innovations as well as continuous enhancements of this material are of crucial
importance to us. Our efforts have been successful: today hardened and tempered steel
strip is one of our key products. We are also an international market leader in this sector.
On the following pages we will introduce you to the variety of hardened and tempered
steel strip grades, and we will also show you how to find the best solution to meet your
particular product requirements.
02
Hardened and tempered steel strip
Your products are versatile – and so is the hardened and tempered steel strip made by CDW.
It is used in vacuum cleaners, lawnmowers and secateurs; it ensures lasting saw blade
sharpness and, in the shape of a spring in the retracting mechanism, will always pull the
seat belt back to the correct position.
You can rely on it at all times:
Hardened and tempered steel strip
We attach great importance to an application-oriented approach and are constantly
enhancing and improving our steel strip, thus extending the application range with
a variety of different microstructures. The material is available as martensitic hardened
and tempered steel strip, as SORBITEX® texture-rolled steel strip or as PT strip.
In co-operation with your company we will develop the optimal solution for all your
individual requirements. We support the development process on the basis of our highly
specialised quality management system and are therefore able to guarantee the highest
product quality and the best results – continuously!
Hardened and tempered steel strip
03
Thickness
0.08 - 4.0 mm
Width
7 - 650 mm
Tolerances
according to EN 10140 and special agreements
Delivery form
pancake coils, oscillated wound coils and fixed lengths
Material
according to EN 10132 3 + 4 and special grades, PT, SORBITEX®
Surface
greyblue, bright, polished, ground, brushed
for further details: www.cdw.de
Excellent innovations
One type of material within our range of hardened and tempered steel strip is
martensitic hardened steel. It fulfils the narrowest tolerances and is extremely flat.
Therefore it is particularly suitable for products demanding precision, homogeneity
as well as hardness, and which at the same time has to withstand high stresses and
strains. Martensite is used e. g. in pneumatic shock absorber plates or in compressor
flapper valves. These devices are exposed to strong cyclic stresses and strains.
Martensite can also be relied upon when manufacturing high-performance saw blades.
Our material guarantees an extraordinary precision for all end products. No matter if
laser cut or machined.
A prime example for what we are able to do with the innovative martensite is the awardwinning “Aerotwin” windscreen wiper with custom-designed flex rails and balanced force
distribution for better sight, improved winter performance and longevity.
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Hardened and tempered steel strip
Outstanding spring suspension
The main feature of our hardened and tempered
steel strip is its versatility, which is particularly
due to the variety of different microstructures
ensuring a wide application range for this
material. One product in this group is PT strip,
one of our specific developments and the best
choice for accurate solutions. The unique material
properties of PT strip allow specific forming
despite high tensile strength. Thus intricate piece
hardening is not necessary – certainly an
advantage for you. Extremely precise springs
and flat springs as well as complex metal working
parts can be manufactured using this specific
material. They are predominantly suitable for
static loads e. g. in connection with various
pressure plates or fasteners elements and
meet the closest form tolerance requirements.
High carbon steel / spring steel
Martensitic hardening and tempering
according to EN 10132-4
Bainite hardening
PT strip
Grades
Tensile strength
Grades
[N/mm2]
Tensile strength
[N/mm2]
34Mn5
PT 90 Mn
800 - 1,000
C45E
PT 100
900 - 1,100
C55S
1,100 - 1,700
PT 110
1,000 - 1,200
C60S
1,150 - 1,750
PT 120
1,100 - 1,300
C67S
1,200 - 1,900
PT 130
1,200 - 1,400
C75S
1,200 - 1,900
PT 140
1,300 - 1,500
PT 150
1,400 - 1,600
C80S
1,200 - 1,900
C85S
1,200 - 2,000
C90S
1,200 - 2,100
C100S
1,200 - 2,100
56Si7
51CrV4
1,200 - 1,700
1,200 - 1,800
Hardened and tempered steel strip
05
Highest force in the smallest space
SORBITEX® texture-rolled steel strips are the
basic material for the production of particularly
robust and reliable springs. They work efficiently
in retraction devices found in dog leashes,
vacuum cleaners and lawnmowers. The secret of
the SORBITEX® steel strip is its texture providing
extreme spring properties, maintained even at
permanent loads.
In order to optimise these properties the
material is undergoing a complex production
process at CDW. We perform a special heat
treatment procedure and strongly cold work of
the microstructure. This is how we achieve the
desired texture.
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Hardened and tempered steel strip
Due to its specific properties SORBITEX® texturerolled steel strip is interesting for a number
of industrial sectors. Primarily the automotive
industry really appreciates the advantages of
this material and uses it in numerous products.
For applications in this industry CDW works in
product development specification oriented.
The retractor springs in seat belts made of our
texture-rolled steel strip, for example, are failsafe, enormously endurable and have a tensile
strength of up to 3,000 N/mm2.
Tensile strength [N/mm2]
Range of specific values
3,200
3,000
2,800
2,600
2,400
2,200
2,000
1,800
Sorbite / PS
1,600
1,400
1,200
1,000
800
Bainite / PT
Martensite / QT
600
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
Strip thickness [mm]
Hardened and tempered steel strip
07
All’s well that ends well
Hardened and tempered steel strip produced by C.D. Wälzholz is a power-pack! It is
wear-resistant and break-proof, of high-grade precision and works reliably even under
strong strains and stresses.
Our highly specialised production procedure covering every step from raw material to
end product ensures that the steel will obtain its valuable properties. Additionally, we
constantly support the entire production process on the basis of our quality and process
management system. Consequently we are able to guarantee a continuously high quality
for all our products.
For the production of hardened and tempered
steel strip CDW uses 4-stand tandem rolling mills
and 20-roll mills, which are able to achieve speeds
of up to 850 metres a minute. Furthermore, we
use the latest computer technology to attain the
required precision; by means of non-contact x-ray
and isotope measuring strip thicknesses are
recorded so that roll positions can be automatically
adjusted. Moreover, strip length and speed data is
collected by means of laser beams.
The subsequent hardening and tempering finally
completes the product. In order to optimise the
microstructure we use appropriate, well adapted
process engineering. Thus we distinguish
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Hardened and tempered steel strip
between sorbitic, bainite and martensitic
processes in this multi-stage process of cold
rolling, heat treatment and second cold rolling.
These procedures differ as to the temperature
of the metal bath and will consequently influence
the development of the required microstructure
properties in each case.
For the production of SORBITEX® texture-rolled
steel strip and PT strip two heat treatment lines
with state-of-the-art process management are
employed. We also have five wide strip lines
and three narrow strip lines for hardening and
tempering of martensitic steel grades.
Round and wound –
our oscillated wound coils
All processes at CDW are subject to a demanding quality and process management
optimising the production of our hardened and tempered steel strip right from the start
and we will not be happy before all our customers are happy! One good example for our
efforts is the continuous enhancement of our oscillated wound coils.
These coils help our customers to stay ahead of competitors in a number of ways. The
increased length of the individual steel strips from 1,000 to 30,000 metres provides for
more economic production and steel strips can be joined by means of modern welding
technology and computer-controlled oscillating winding procedure.
Thanks to 30 times longer operating times labour-intensive set-up times and
unprofitable shutdown times are minimised.
Here they are again in short form – the advantages of our oscillated wound hardened
and tempered steel strip coils:
» Strip widths of up to 70 mm
» Operating times / strip lengths up to 30 times longer
» Individual coil widths of 250 - 550 mm
» Jumbo coils with a weight of up to 3,500 kg
Hardened and tempered steel strip
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The best travel insurance – our packaging
To ensure quality for our customers we have the
highest demands in material and production.
For us at C.D. Wälzholz it is important that our
hardened and tempered steel strip coils reach
your company in perfect condition. Therefore we
aim for the highest quality and exacting standards
not only in regards to production and material, but
also with respect to packaging and shipment. Our
modern automatic packaging equipment can
guarantee smooth logistics between production
line and shipping department and protect each
product according to our customers’ requirements.
Hardened and tempered steel strip can be supplied
in a number of forms, namely in fixed lengths,
pancake coils with an outside diameter of up to
1,850 mm and oscillated wound coils with a weight
of up to 3.5 tons.
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Hardened and tempered steel strip
The different the transport options to national or
international destinations are, the numerous our
packaging options are. Take our heavy-duty
overseas packaging, for example. It will most
definitely withstand the strains of long and rough
transportation across the ocean.
Behind every packaging idea there is one thought:
Sometimes less is more! We will never use more
material than is absolutely necessary. After all,
this is for the benefit of the environment and of
our customers. Owing to our long international
experience we have continuously improved our
packaging: optimal protection, clear marking and
distinct traceability are the results of such an
extensive experience.
C.D. Wälzholz –
at home everywhere in the world
Steel is an extremely versatile material. The C.D. Wälzholz Group of Companies is just as
versatile itself. As a progressive German cold rolling mill with a long tradition,
C.D. Wälzholz today has subsidiaries and agencies all over the world. Therefore we are in
a position to offer our international customers hardened and tempered steel strip in
virtually any type and grade required – everywhere in the world.
Satisfied customers, highest quality as well as a responsible handling of the environment
are our goal. Always.
Hardened and tempered steel strip
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Cold rolled high carbon steel strip
Hardened and tempered steel strip
Electrical steel strip
Cold rolled low carbon steel strip
Bonderized steel strip
Narrow steel strip
05/13
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Profiles
C.D. Wälzholz KG
Feldmühlenstr. 55
58093 Hagen
Germany
Phone: +49 (0) 23 31- 9 64 - 0
Fax:
+49 (0) 23 31- 9 64 - 21 00
Internet:www.cdw.de
E-mail:info @ cdw.de
Locations:
Hagen, Hohenlimburg, Plettenberg, Oberkochen, Iserlohn/Germany
Götzis/Austria . Thiers/France
São Paulo/Brazil . Cleveland, Ohio/USA . Taicang/China