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FineXcell®: high performance fine-grain steels
The FineXcell® series regroups V & M TUBES’
proprietary grades for fine-grain steels.
FineXcell® series displays the perfect balance
between high strength, excellent toughness, resistance to brittle fracture, and excellent suitability for welding! It is the perfect combination for
the design of demanding steel structures, in the
most cost effective way.
Our FineXcell® series is available both in circular mechanical and square or rectangular structural product range (under our MSH brand).
This brochure focuses on their specific advantages and design requirements for circular
mechanicals. Please refer to our other product
line brochures for further information on the rest
of our offering.
V & M TUBES for standard grades
V & M TUBES specific branded grades
Grade portfolio Indusry division
Engineering Grades
Spirafort® series
EN 10294
Advanced
Engineering Grades
Avadur® series
ASTM A 519
Oceanfit® series
API 5L, EN 10225
FineXcell® series
Stahl-EisenWerkstoffblätter
Basic Mechanical Grades
Multicert® series
EN 10297, EN 10210
E355, S355J2H,
Grade B, C, …
Forterior® series
EN 10297, EN 10210
Alloyed heat treatable steels
25CrMo4, 34CrMo4,
42CrMo4, Grade 4130,
Grade 4140, ...
Unalloyed heat treatable steels
C35E, C45E, C60E,
Grade 1045, ...
Case hardening steels
16MnCr5, C10E,
20NiCrMo2-2, …
Increasing technical requirements
2
Offshore Grades
Fine-Grain HighStrength Grades
X52, X65, X80, ...
Round tubes
Hollow bar
S460NLH,
P690QL1, ...
Square and rectangular
hollow sections
V & M TUBES grade brands meet and in many cases surpass
the requirements of the relevant standard grades. The respect
ive compliance with the standard is clearly indicated in the material datasheets, orders and certificates.
Fine-grain steels development enabled record
lifting capacities
FGS 63 V
~ 600 MPa
St 52
355 MPa
in
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FineXcell® 700
FineXcell® 780
FineXcell® 800
FineXcell® 900
~ 700 - 900 MPa
FineXcell® 960
960 MPa
3200 tons
n
1600 tons
1000 tons
800 tons
250 tons
45 tons
1960
1970
1980
1990
2000
2010
lifting capacity
for latticed
boom
cranes
MaximumMaximum
lifting capacity
for latticed
boom
cranes
High-strength steels for recordbreaking performance …
Extremely high performance such as that shown
by record-breaking cranes and hydraulic cylinders can only be achieved with highly sophisticated materials. The FineXcell® series developed
by V & M TUBES provides here all the safety
needed to design steel structures for even more
demanding operating conditions. The family
includes grades with yield strengths up to the
impressive level of around 1000 MPa, enabling
your structure to handle any type of load! The
development of this grade series has opened up
new fields in structure design: with FineXcell®,
structures can now be realised that, for technical
or economic reasons, would be impossible with
lower-strength steels!
Potential weight savings for construction high-strength fine-grain
Potential weight savings for construction
steels compared to S275
high-strength fine-grain steels compared to S275
100%
tension / compression
50%
bending
… and lightweight design!
With highly stressed steel structures, the structure’s dead weight is a major factor in its cost
effectiveness. Hence, there is a strong interest in
reducing the dead weight without any loss of
load-bearing capacity, i.e. the structure’s strength
and the safety of its components. It is a question
of satisfying this demand for lightweight construction while simultaneously improving the
safety of highly stressed structures. This can be
easily achieved with our FineXcell® grades,
whose higher strength allow you to reduce the
wall thickness and thus weight of the tubular
structure. And each kilogram gained means
improved mobility!
With the same working conditions, using
FineXcell® 890 instead of simple S275 reduces
weight up to 70 % in the design of the structure.
Wall thicknesses are then thinner, and thus easier
to process!
0%
S275
FineXcell® FineXcell®
360
460
FineXcell® FineXcell® FineXcell® FineXcell® FineXcell®
700
780
800
900
960
3
The reduction of wall thickness is also important
for applications having to withstand internal
pressure, such as hydraulic cylinders. The use of
the FineXcell® series makes better mechanical
properties possible while using less material.
But saving weight doesn’t only mean savings
in the weight of the structure and improved
mobility. It also of course means less material
to purchase for the same use, and less weight to
handle and to transport.
We also offer FineXcell® material according to
EN 10216 standard, with leakage test for pressure applications. Please contact us for further
details on materials available.
Similar high-strength grades have also been
developed for offshore application. Please refer
to our Oceanfit® series for further information!
FineXcell® 900
FineXcell® 800
FineXcell® 780
FineXcell® 700
Forterior® 590
P355N
Thinner walls for pressure applications with
FineXcell® steels
4
Mechanical properties (all other testing requirements according to EN 10210-1 and EN 10216-3)
Steel grade
Delivery
condition1)
Yield strength
ReH min in MPa2)
Tensile strength
Rm in MPa2)
Elongation
Amin in %
Min. average absorbed
energy KV in J
Long.
Transv.
490 - 650
22
20
27 at –30 °C
360
490 - 650
22
20
25 at –60 °C
N
360
167 at +400 °C
490 - 650
390 at +400 °C
22
20
27 at –30 °C
FineXcell® 460
ImpactFIT 30
N
460
560 - 720
19
17
27 at –30 °C
FineXcell 460
ImpactFIT 60
N
460
560 - 720
19
17
25 at –60 °C
FineXcell® 460
TempFIT 400
N
460
235 at +400 °C
560 - 720
460 at +400 °C
19
17
40 at –20 °C
FineXcell® 700
ImpactFIT 40
QT
700
770 - 960
16
14
45 at –40 °C
FineXcell® 700
ImpactFIT 60
QT
700
770 - 960
16
14
40 at –60 °C
FineXcell® 700
TempFIT 300
QT
700
510 at +300 °C
770 - 960
620 at +300 °C
16
14
40 at –60 °C
FineXcell® 780
ImpactFIT 40
QT
780
820 - 1000
15
13
45 at –40 °C
FineXcell® 800
ImpactFIT 40
QT
800
850 - 1030
15
13
40 at –40 °C
900
960 - 1110
14
12
45 at –40 °C
960
980 - 1150
10
–
27 at –40 °C
FineXcell® 360
ImpactFIT 30
N
360
FineXcell 360
ImpactFIT 60
N
FineXcell® 360
TempFIT 400
®
®
FineXcell® 900
QT
ImpactFIT 40
Chemical
composition (in % by mass)
FineXcell® 960
QT
ImpactFIT 40
1)
N: normalized or normalized formed; QT: quenched and tempered; 2) valid for the smallest wall thickness range given in the respective material data sheets;
Chemical composition (in % by mass)
Steel grade
C
FineXcell® 360
ImpactFIT 30
max.
0.20
FineXcell 360
ImpactFIT 60
max.
0.18
FineXcell® 360
TempFIT 400
max.
0.20
®
Si
Mn
max.
0.50
0.90 to
1.65
P
max.
FineXcell 460
ImpactFIT 60
0.025
Ni
max.
W
V
Al
N
max.
Ti
max.
Nb
max.
0.015
max.
0.30
max.
0.08
0.50
–
max.
0.10
min.
0.020
0.015
0.03
0.05
max.
0.30
max.
0.10
0.70
–
max.
0.20
min.
0.020
0.020
0.03
0.05
max.
0.80
0.20 to
0.40
0.40
0.10 to
0.70
0.05 to
0.12
0.015 to
0.050
0.020
0.05
0.05
max.
0.80
0.20 to
0.40
0.40
0.10 to
0.70
0.05 to
0.12
0.015 to
0.050
0.020
0.05
0.05
0.020
max.
0.20
0.10 to
0.50
1.20 to
1.70
0.025
0.015
0.020
0.14 to
0.18
0.20 to
0.50
1.20 to
1.70
0.14 to
0.18
0.20 to
0.50
1.20 to
1.70
FineXcell® 780
ImpactFIT 40
0.14 to
0.18
0.20 to
0.50
FineXcell 800
ImpactFIT 40
0.10 to
0.18
FineXcell® 900
ImpactFIT 40
FineXcell® 960
ImpactFIT 40
FineXcell 700
ImpactFIT 60
Mo
0.020
FineXcell® 460
TempFIT 400
FineXcell® 700
ImpactFIT 40
Cr
0.020
FineXcell® 460
ImpactFIT 20
®
S
max.
0.025
0.015
0.025
0.015
1.20 to
1.70
0.025
0.015
max.
0.80
0.20 to
0.40
0.40
0.10 to
0.70
0.05 to
0.12
0.015 to
0.050
0.020
0.05
0.05
0.20 to
0.50
1.20 to
1.70
0.025
0.015
0.40 to
0.90
0.20 to
0.50
0.40
0.10 to
0.80
0.03 to
0.12
0.015 to
0.050
0.020
0.05
0.06
0.14 to
0.18
0.20 to
0.50
1.20 to
1.70
0.020
0.010
0.50 to
0.90
0.30 to
0.70
0.40
0.40 to
0.80
0.03 to
0.12
0.015 to
0.050
0.020
0.05
0.06
max.
0.20
max.
0.50
1.20 to
1.70
0.020
0.010
0.40 to
1.00
0.30 to
1.00
0.40
0.40 to
1.50
max.
0.02
0.010 to
0.050
0.025
0.03
0.05
®
FineXcell® 700
TempFIT 300
®
5
Impact toughness test temperature
– 60 °C
– 50 °C
FineXcell® 360
ImpactFIT 60
FineXcell® 460
ImpactFIT 60
S355
NLH
S460
NLH
S355
NH
S460
NH
FineXcell® 700
ImpactFIT 60
FineXcell® 700
ImpactFIT 40
– 40 °C
FineXcell® 780
ImpactFIT 40
– 30 °C
– 20 °C
– 10 °C
Yield strength
6
FineXcell® 800
ImpactFIT 40
FineXcell® 900
ImpactFIT 40
FineXcell® 960
ImpactFIT 40
Outstanding toughness even at
very low temperatures
But fine-grain steels do not only feature high
strength. Their key characteristic is their outstanding toughness as well as their excellent
resistance to brittle fracture. While most of
FineXcell® grades show excellent impact values
at –40 °C, some were developed to withstand
im-pact tests at temperature levels as low as –60
°C. FineXcell® are then the favourite choice
for low-temperature applications, with Charpy
values unrivalled by other grade families.
Those excellent characteristics are due to their
fine-grain structure. This can be clearly illustrated by comparing the impact resistance of a
standard S355 grade to the lowest fine-grain
FineXcell® 360, with the same yield strength.
The FineXcell® 360 achieves notably better
impact test results thanks to the normalizing
heat treatment, which significantly improves the
microstructure. The very high Charpy values
achieved with the FineXcell® series are attained
in their quenched and tempered condition, for
yield strengths exceeding 460 MPa.
Effect of grain size on notched bar impact energy
Impact energy
FineXcell®
360
Coarse grain
S355
Temperature
7
1 µm
Weldability
Cross section of a FineXcell® 700 Impact FIT 40 weld seam; HV-bevel preparation
was chosen to produce a steep edge for heat affected zone testing.
Correlation between SMYS and CEIIW of different grades
SMYS for walls ≤ 16 mm in MPa
1000
42CrMo4, grade 4140 to
125 ksi SMYS
FineXcell® 900
750
FineXcell® 700
500
FineXcell® 460
FineXcell 360
S355J2H, E355, grade C
®
250
Q&T
Normalised
0
0.3
0.5
Carbon equivalent CEIIW
TIG-dressing of an FineXcell® 960 ImpactFIT 40 weld seam
8
Being used for mechanical applications, our
FineXcell® tubes of course need to be welded to
other tubes or components. Their excellent
weldability is due to their high-quality prematerial with very low impurities and a stable
production process yielding a homogeneous
microstructure. To ensure the good weldability of
quenched and tempered high-strength
FineXcell® grades, the relatively low carbon
equivalents are adjusted. Depending on the
strength level and application, all common
manual and mechanised welding processes may
be used. Suitable welding consumables with
adequate strength levels are available from wellknown suppliers of filler material.
0.7
V & M TUBES has carried out weldability tests
for a wide range of dimensions and strength
levels of FineXcell® alloys. As an example of a
typical weldability test on a pipe of FineXcell®
700 ImpactFIT 40, the picture on the left shows a
cross section.
To characterise the performance of V & M
TUBES steel grades, welds are tested with hardness measurements, tensile and bend tests and
for toughness behaviour. Toughness is commonly
tested with Charpy V-notch tests and, if necessary or on customer’s request, with CTOD tests.
Bead-on-pipe tests or Tekken tests are performed
to determine the material’s welding behaviour
and enable the customer to produce crack-free
root passes. For special projects, investigations
on adapted welding technologies can be performed as well as application-related testing.
Data from weldability tests are collected in a
V & M TUBES database so that customers can be
easily provided with basic welding information,
like heat input, pre-heating temperatures and
filler material. Since welding procedures are
dependent on bevel design, wall thickness or
steel grade, it may be necessary to adapt the
parameters of test welds to application welds to
achieve similar results.
Independently of the welding information
from V & M TUBES, designers and welders have
to conform to technical rules and standards and
the state of technology.
For more information
on FineXcell®’s welda
bility,
please ask for V & M
TUBES
welding information
for your
chosen steel grade.
Fatigue test of weld seams for crane applications
9
Applications
Cranes
The demands placed on modern cranes are as
many and varied as their applications and design.
The challenges are growing, with a need for
higher maximum lifting capacities and lifting
heights, without sacrificing rapidity and mobility.
The FineXcell® series is regularly used in all
types of crane construction. Using such superior grades permits higher lifting capacities
and lifting heights – for instance for the recent
record-breaking crawler cranes with lifting
capacities of several thousand tonnes. FineXcell®
also achieves substantial savings in weight at
the lattice jib extension of mobile cranes, thus
permitting higher lifting capacities at maximum
reach. Additionally, a low service weight greatly
improves crane mobility.
10
For harbour cranes, for instance, the savings in
weight permit higher operating speeds. And the
lattice structures increase lifting capacity and
the number of load cycles per unit of time.
Any type of crane can benefit from the
high performance features of our
FineXcell® series.
Hydraulic cylinders
Hydraulic cylinders can be found in an extremely
wide range of applications. Many of them are
used in extreme conditions, calling for great
attention to safety. With the FineXcell® series,
even higher properties can be achieved without
compromising on safety.
The FineXcell series is available in an impressively wide range of dimensions and tight tolerances in order to minimize the machining operations required on the tubes. Since they are already
close to the final shape of the cylinder body, the
material loss is minimized: a great advantage for
our customers.
And many other applications!
®
Our FineXcell® grades are also used in a number
of applications where they bring value to our
customers. High-strength properties are beneficial on winch drums, as well as on the columns
of truck loading cranes. Shock absorbers for
heavy-duty vehicles and other structural parts are
also among the numerous potential applications
for fine-grain steels.
11
Advanced quality with carefully controlled FineXcell® production
The excellent property profile of the FineXcell®
series can only be achieved with rolling and heat
treatment processes geared to the grade of steel,
combined with optimally adapted, product-driven
steel compositions.
Fine chemistry for improved
properties
The development of the fine-grain steels goes
back to the 1950s. One of the decisive factors for
the development of steel products that fully
satisfies the varied requirements of the market
has been progress in metallurgy.
Chemistry plays an important role here.
FineXcell® grades have lower contents of phosphorus and sulphur, and improved purity: this
yields a lower tendency to brittle fracture and
good toughness. In addition, their excellent
strength and toughness properties are
achieved thanks to a micro-alloying
concept. The high strength of
FineXcell® is a result of the grain
size: the finer the microstructure,
the higher the yield strength. The
micro-alloying elements such as
V, Nb and Ti form a large number
of small, homogeneously distributed precipitates. These precipita-
tes delay grain growth during hot rolling and heat
treatment, and facilitate a finer microstructure.
1 µm
Finer micro structures can be reached with dedicated
heat treatment
20 µm
As rolled
12
20 µm
Normalized
20 µm
Quenched & tempered
Carefully selected hot-rolling &
heat treatment parameters
Fine-tuned chemical composition
Suitable hot rolling ...
... and heat treatment
Excellent tube characteristics of
FineXcell® grades
Our FineXcell® series are produced in highperformance push bench, continuous mandrel
and plug rolling mills. They are also available
from our new PFP (Premium Forged Pipes) mill.
For large diameters and/or heavy wall thicknesses we use the pilger rolling process.
Heat treatment is the key process for ensuring the
desired characteristics. The lower range of our
fine-grain steels, our FineXcell® 360 and
FineXcell® 460, are normalized. The process is
carried out in high-performance plants and starts
with through-thickness reheating from ambient
temperatures to temperatures above austenitizing
temperature (Ac3). Heating is followed by cooling back to ambient temperature in still air.
Minimum yield strengths of up to 460 MPa can
be attained in this normalized condition.
For higher properties, quenching and tempering
are carried out: accelerated cooling with water
from austenitizing temperature is carried out so
that the austenite is converted to martensite. This
is the step of quenching which leads to high
tensile properties. The tempering done afterwards
ensures a balanced combination of tensile and
impact properties. Contrary to direct hardening,
this quenching & tempering process provides a
more uniform combination of properties through
the tube’s cross section, circumference and
length. FineXcell® grades achieve yield strengths
of up to around 1000 MPa and Charpy values
down to test temperatures of –60 °C. These heat
treatments need to be conducted carefully in
order to achieve and maintain the desired finegrain size and mechanical properties.
FineXcell® grades are characterised – in addition
to the tensile properties at room temperature – by
impact values down to low test temperatures
(ImpactFIT) and for some grades also tensile
properties at elevated test temperatures
(TempFIT).
13
FineXcell® design book
Technical support
Hot forming
V & M TUBES cooperates closely with its customers, jointly developing a tailored concept of
tube materials and dimensions for each structure.
We provide, when necessary, design verifications for individual steel tube components or
assemblies, for example in order to obtain the
building authorities’ approval. We also offer
support in drawing up application-related welding recommendations as well as fatigue tests for
components.
Hot forming, i.e. forming at temperatures above
the maximum permissible temperature for stressrelieving, can usually be carried out without
difficulty. The rules applicable to hot forming
should also be observed for local adjustment and
straightening work, during which the temperature
must be monitored.
Where normalized steels are concerned (up to
FineXcell® 460), the workpiece temperature
during hot forming must not exceed 1050 °C
because of the risk of grain coarsening. Excessive soaking must also be avoided. Before the
final hot forming stage or in single-stage hot
forming, the workpiece should not be heated to
more than 980 °C.
If, however, grain coarsening does occur, intermediate cooling to temperatures below 700 °C
is necessary before the final heat treatment.
The forming process should be completed at
above 750 °C or, if the degree of forming does
not exceed 5 % during the last stage, at above
700 °C. This does not include straightening and
smoothing processes.
Forming with a predominance of upsetting, e.g.
forging, can be carried out in the upper temperature range, while forming in which stretching
occurs should be effected in the lower temperature range.
After hot forming in the conditions described
above, cooling should take place in still air. The
rate of cooling depends on the wall thickness.
Since excessively slow cooling can have a detrimental effect on the strength and toughness
properties, an accumulation of heat must be
avoided at all costs. If the wall thickness is small
and the steel is normalized retarded cooling or
tempering may be necessary.
If the above conditions are complied with, normalizing can be omitted as long as the properties
specified in the technical delivery conditions, on
the VdTÜV data sheet, the V & M TUBES’s data
sheet or the order are complied with. Otherwise
or if demanded by higher-order regulations, the
steel has to be normalized.
Cold forming
FineXcell steels provide superior cold formability. Such operations are easily carried out within
the scope of the steels’ deformability characterized by uniform elongation. During cold forming,
it is important to take into account the additional
force required due to the enhanced yield strength
and the resultant intensified springback. In addition, the change in strength properties caused by
cold forming and the impairment of workability
and toughness characteristics must also be borne
in mind.
®
Cold forming is permitted at elevated temperatures, up to just short of the maximum allowable
stress-relieving temperature. If, after relatively
extensive cold forming, subsequent heat treatment is required to diminish strain hardening and
improve the toughness properties impaired by
forming, stress-relieving usually suffices unless
repeated normalization or quenching & tempering are specified in the acceptance conditions or
technical rules. It should be remembered that the
effect of cold forming cannot be entirely reversed
by stress-relieving.
14
The hot forming temperature for quenched &
tempered steels, starting from FineXcell® 690
should not exceed 1050 °C. After hot forming,
quenching & tempering must always be carried
out again in accordance with V & M TUBES’s
material datasheets.
It is advisable to follow the recommendations of
sections 3.1 (hot forming) and 3.2 (cold forming)
of SEW 088. V & M TUBES engineers are prepared to give support for your specific forming
requirements.
Machining
FineXcell® series can usually be machined
without any particular concern. It is of course
important to select the right tools and machining
conditions, adapted to each grade mechanical
properties.
11
Technical Consulting
telephone +49 211 960-2860
telefax +49 211 960-2350
e-mail
thomas.mueller@vmtubes.de
Vallourec Group
V & M D02B0006B-12GB
V & M DEUTSCHLAND GmbH
Industry
Theodorstraße 90
40472 Düsseldorf · Germany
telephone +49 211 960-3580
telefax +49 211 960-2373
e-mail
info.service@vmtubes.de
www.vmtubes.com