ThyssenKrupp VDM - Innovations

ThyssenKrupp VDM GmbH
Plettenberger Str. 2
58791 Werdohl
The new open-die forge shop of
ThyssenKrupp VDM
Die neue Schmiedelinie bei ThyssenKrupp VDM
Ein Unternehmen
von ThyssenKrupp
Stainless
ThyssenKrupp VDM
tk
Hans-Peter Jaeger, Franz-Josef Wahlers and Christian Dettmer
The new open - die forge shop
of ThyssenKrupp VDM
ThyssenKrupp VDM GmbH has invested strongly to increase its competitiveness. A major part of more than 70
million € strategic investment program, which was launched in 2006, was spent on the construction of the new
forging line at the Unna production site of ThyssenKrupp VDM GmbH. The facility is one of the most advanced
open-die forging plants in the world and was realized in only two years from first idea to the date of commissioning on 15th of Febuary 2008. All milestones with regard to the new forging line were achieved during the first
couple of month in operation.
Die ThyssenKrupp VDM GmbH hat zur Erhöhung der Wettbewerbsfähigkeit umfangreiche Investitionen getätigt.
Ein großer Teil des mehr als 70 Mio. € umfassenden strategischen Investitionsprogramms, das im Jahre 2006
gestartet wurde, ist für den Bau der neuen Schmiedelinie und die Erweiterung der Umschmelzkapazitäten am
Standort Unna der ThyssenKrupp VDM GmbH verwendet worden. Der neue Schmiedebetrieb gehört zu den
modernsten Freiformschmieden der Welt und wurde in nur zwei Jahren von der ersten Idee bis zur Inbetriebnahme am 15. Februar 2008 realisiert. Alle Projektziele bez. der terminlichen Realisierung der Investition,
dem Anlagenlayout und der erzeugten Produktqualität konnten in den ersten Monaten der Hochfahrphase des
neuen Betriebes verifiziert werden.
ThyssenKrupp VDM GmbH, a
subsidiary of ThyssenKrupp
Stainless AG, has been developing high-performance materials for challenging applications
and processes for more than 75
years and is one of the world’s
leading manufacturers of Nickel
Alloys and high-alloy special
stainless steels.
The product range includes
strip, sheet, rod, forgings as
billets and bars, pipe material,
wire as well as precision mechanical parts, figure 1. The company headquarters is based in
Werdohl, Germany and further
production sites in Germany are
located in Unna, Altena and Siegen. In the USA, ThyssenKrupp
VDM operates plants in Florham
Park (New Jersey) and Reno (Nevada) specialized in the production of high-temperature materials for the aerospace industry.
A global sales organization with
14 branch offices, combined
with service centers in Guangzhou (China) and Melbourne
(Australia), ensures an optimum
world market presence. In fiscal
year 2007/2008 the company
supplied more than 42000 t of
products and generated sales of
about 1.2 billion € with a global
workforce of 1800 employees,
figure 2.
1.
ThyssenKrupp Stainless major business fields
Hauptgeschäftsfelder der Thyssenkrupp Stainless AG
The company’s Nickel Alloy and special stainless steel
products are used in aerospace, oil and gas, energy, environmental, automotive and many other industry sectors.
The strategy of ThyssenKrupp VDM GmbH comprises predominately significant growth of its market share in high
performance alloys for the oil & gas and the aerospace
markets.
Although ThyssenKrupp VDM GmbH was producing and
delivering billets and bars for these sectors in the past
there has been a limitation in production and lead times,
as forging was contracted with third party conversion partners outside the TK-Group with limited capacities and capabilities. On the other hand ThyssenKrupp VDM GmbH
strategy targets on being process owner of all sensitive
operations which are affecting quality issues. Consequently this resulted in the idea to plan the construction of
an own forging line in early 2006.
An important part of the layout considerations was not
only to design a forge shop with the best possible capabilities for forging Ni- and Co-alloys but also to allocate a
significant capacity for active conversion for other companies in order to increase utilization of the new plant.
Besides the opportunity for insourcing forging activities
with regard to the sister company TKL-Titanium within the
Stainless Group a substantial tonnage for forging of steel
grades was contracted in a long term agreement a year
before the new plant went on line.
2.
ThyssenKrupp VDM GmbH production sites
Produktionsstandorte der ThyssenKrupp VDM GmbH
3.
Plant layout of ThyssenKrupp VDM GmbH Unna site with new forge shop
(top left)
Layout des Werks Unna der ThyssenKrupp VDM GmbH mit der neuen
Schmiede (links oben)
Milestones – Time schedule
The project was started with the kick off meeting on 19th
of April 2006, parallel to the internal company approval
process. At that point in time the general time schedule
was defined. The major milestones were:
• ThyssenKrupp AG supervisory board approval by August 2006
• Order placement of main machinery by September
2006
• Start of bay construction in November 2006
• Start of hot commissioning in February 2008
• Internal product qualification process March to
August 2008.
From April to August 2006 the project team compiled
the technical specifications for the forging press, the manipulators and the heating furnaces followed by technical
discussions with several potential suppliers for the main
machinery. This resulted in the first order placement on
September 20th 2006 for the press forge followed by the
manipulators order in early October 2006. Bay construction started as scheduled with the ground breaking ceremony on November 30th 2006, after getting the preliminary authority approval for the whole investment already
in August 2006.
Although there were many obstacles during the machine construction, VDM project management could in mutual cooperation with the main suppliers discover these
obstacles in time and resolve critical issues before the targeted delivery date was going to be in danger of slipping.
This led to on time finishing of the civil engineering works
and on time delivery of the press parts, manipulators and
furnaces as well. After a total project time of 22 months
since kick off, the hot commissioning took place on 15th
of February 2008, one week ahead of schedule. By the
20th of March the main work regarding the hot commissioning was finalized.
Accordingly the internal product qualification process
started on time. During this process all forging parameters
for most of ThyssenKrupp VDM GmbH forging products
could be developed prior to the starting of first customer
related production in May 2008.
vers a wide range. It spans from rounds of between 150
and 1100 mm to flats of about 1700 mm x 600 mm maximum size. The ingot size range being forged is between
1,5 t and 60 t. The press design in terms of e.g. daylight
and max. press force derives from the above mentioned
demands regarding alloy and size portfolio.
Scope of alloys and dimensions
The ThyssenKrupp VDM GmbH alloy portfolio is the main
element in the range of alloys to be forged on the new
production line. Additionally, titanium grades for ThyssenKrupp Titanium GmbH are being forged. In order to utilize
the capacity of the new Forge Shop at its optimum a substantial contract conversion is part of the planning. From
Carbon Steel grades to Stainless Steel and Copper Alloys
a wide range of different alloys are involved.
Similar to the alloy variety the scope of dimensions co-
4.
View on the forge shop building
Die Hallen des neuen Schmiedebetriebs
5.
Layout plan of the forge shop; footprint
Grundriss und Maschinenaufstellungsplan des Schmiedebetriebs
Layout of the New Forge Shop
The plant layout of the Unna mill and the general layout
of the new forge shop will be described now.
Plant layout of the Unna mill
The new Forge Shop was erected on the Unna production site of ThyssenKrupp VDM GmbH, where the melting
shop is located, figure 3. On about 400000 m2 ThyssenKrupp VDM GmbH operates an open melt shop with a 30
t Electric Arc Furnace (EAF) and three 16 t Induction Furnaces (IF). Secondary metallurgy facilities such as Vacuum
Oxygen Decarburization (VOD) and Vacuum Ladle Furnace
(VLF) are available. Casting takes place in conventional
ingot casting with mould sizes from 1.5 to 26 t and a semi
continuous slab caster for plate and strip production. The
special melt shop in a separate building comprises a 20 t
VIDP-Furnace, which can be extended with a 30t crucible.
This is predominantly used for melting of Superalloys and
casting in electrode moulds under vacuum for subsequent
remelting in ESR or VAR processes. ESR and VAR facilities
are located directly adjacent in a separate building, which
as part of the investment projects has been extended to
provide space for 5 additional remelting furnaces. Two
spaces are already occupied by new VAR and ESR facilities. The largest ingot size on VAR is 30 t on ESR 20 t.
Including the new forge shop crew about 320 employees
are engaged in a yearly production of more than 70000 t
ingots at the Unna mill.
General Layout of the new Forge Shop
The general forge shop setup as well as the machine
specifications were developed under two criteria. Both
shall provide excellent conditions for the special demands
of Super Alloys and at the same time offer best opportunities to serve a wide range of possibilities for contract
conversion for other companies.
Following this target the construction phase started in
November 2006 with an area of about 30000 m2 which
had been developed for the erection of the forge shop
building, considering the possibility to extend the area under roof for extending activities in finishing of forgings in
a later step.
The new forge shop building consists of three production bays with about 11000 m2 under roof, figure 4. The
central main bay has a length of 145 m, a width of 30 m
and a height of 23m. The two side bays are 125m long
with a height of 18 m each and widths of 26 and 28 m.
The side bays are occupied predominantly by the heating furnaces. Initial equipment includes 11 heating furnaces. Between the main bay and side bays space for another 9 furnaces of similar dimensions is available to cater
for increasing heating/annealing demand. Additionally the
width of the side bays can accommodate the next investment steps in finishing equipment for forgings as well.
The forge press and the two railbound manipulators are
located in the main bay. Directly beside the forging line an
area of about 1000 m2 divides one of the two side bays.
All electrical and hydraulic supply units for the forge shop
are located there, close to the press. A part of this area
is occupied by the water cooling plant, which is providing
cooling capacity for all hydraulic systems and the water
quench tank.
The tank is positioned directly parallel to the track of one
of the manipulators. This guaranties the shortest transfer
times. The maximum length of pieces that can be quenched is about 11 m. Tank cross section is 3 m x 3 m.
The complete building is equipped with an automatic
fire detection system including the whole shop floor area.
All supply rooms are connected to an automatic fire extinguishing system based on inert gas for all electric control
rooms and water systems for the others.
6.
45 MN press and railbound manipulators
45 MN Presse mit schmiedegebundenen Manipulatoren
7.
Technical key data of 45 MN press
Technische Daten der 45 MN Presse
Technical key data
The technical key data of the 45-MN press, of the manipulators and transport units and of the heating furnances
will be presented now.
The 45MN Press
The Forging Press is designed as a four column press
and has a total height above shop floor of about 13 m with
a weight of more than 700 t. Due to difficult soil conditions
and statutory requirements a lot of design work was conducted on the issue of vibration.
Finally the press is based on 12 shock absorber blocks
containing a total of 250 single springs combined with
damping devices. The press basement is additionally decoupled from the other bay or machine basements in the
new building. Vibration measurements during production
proved that this design emits only very limited oscillation
levels far beneath the limit value.
The Forge Press has a maximum press force of 45 MN.
Three equally designed press cylinders transmit the force
proportionately to the moving cross head. By activating
all three, two or only one of the cylinders, the penetration speed can be increased if less press force is needed,
figure 6.
The hydraulic system of the press contains 14 pressure
pumps providing a nominal pressure of maximum 350 bar
for achieving the maximum press force of 45 MN. With
this setup and the 3-cylinder design a wide range of adapted penetration speeds from near zero to max. 170mm/
sec are possible. This offers the opportunity of providing
a fast process when needed e.g. in finishing and/or for
highest productivity figures. On the other hand by selecting pumps the penetration speed can be adapted to the
specific demands according to alloy restrictions. This is an
important issue considering the variety within the scope
of alloys and dimensions, which will be processed on the
new press.
The Forging Press is equipped with a die shifting device
designed for three die positions and a die magazine covering space for four additional dies. The press table can
be shifted to either side of the press with a stroke of 4m
for loading and unloading of e.g. upsetting parts.
The technical key data of the 45 MN press are summarized in figure 7.
The Manipulators and transport units
The manipulator unit contains two railbound manipulators (SSM 1000 and SSM 300), one pop up turn table and
a mobile transport manipulator (MTM300) for charging
and discharging the batch furnaces.
The railbound manipulators provide dynamic features,
which in terms of acceleration and speed of all movements
support the press speed capabilities. Although both machines are of different dimensions they can be operated
in a combined dual manipulator mode for forgings up to
18 t ingot size. This range covers almost all Nickel Alloy
ingots. Ingots in the range of 18 to 60 t are processed only
with the SSM 1000. For loading, unloading and turning of
ingots and forgings, a 60 t pop up turn table is installed
between the tracks of the SSM1000.
The transport of ingots and forgings between the forging
line and the heating furnaces is performed by either bay
crane or MTM 300. MTM 300 is designed to carry loads
from 100 to 1000 mm in diameter with a maximum weight
of 8 t. It is designed for fast transport from the batch furnaces to the forging line. Ingots and forgings heavier than
8t are moved by the bay crane with two lifting units with
max. carrying capacity of 80 t.
The technical key data of the manipulators are shown
in figure 8.
8.
Technical key data of manipulators
Technische Daten der Manipulatoren
Heating furnaces
The installed heating capacity contains five Batch Furnaces (BF) and six Car Bottom Furnaces (CBF), figure 9.
All furnaces are equipped with natural gas flat burner
systems. The combustion air preheating is provided by a
central recuperator system at each unit. Maximum process
heating temperature of 1300 °C is specified. Due to the
necessity of very tight temperature tolerances in processing Nickel and Titanium Alloys especially for aerospace
applications temperature uniformity in the working zone of
the batch furnaces and the 70 t CBF are periodically surveyed according to AMS 2750. The furnaces are capable
for max. +/-10K deviation from set point temperature above 750 °C. Figure 10 shows the 70 t car bottom furnace
during hot commissioning on the 15th of Feburary 2008.
The furnace control system is linked to a central furnace visualization system as well as to the new Forge Shop
Management System.
The technical key data of the furnances are summarized
in figure 11.
IT environment in the new Forge Shop
9.
Batch furnaces and one of the 70 t car bottom furnaces
The new forge shop also included a new shop management system and auxiliary systems which will be described next.
Kammeröfen und einer der 70 t Herdwagenöfen
10.
70 t car bottom furnace during hot commissionong on 15 Feb 2008
70 t Herdwagenofen während der Inbetriebnahme der Schmiede am 15.02.08
Forge Shop Management System
The new forge shop is embedded in the IT-world of ThyssenKrupp VDM GmbH. Therefore part of the project has
been the programming of the related software modules.
Besides the Order Management System (SAP) emphasis
was put on the Quality Data System (PRINS) and the Forge
Shop Management System (SLS). Both PRINS and SLS
are developed in-house and are focusing on overall data
collection. This includes all actual press, manipulator and
furnace data. On the other hand, all set point data such as
heating/reheating curves and forging schedules are stored
in these systems and linked to the material code of the
products to be forged. Moreover SLS provides 100% material tracking from the moment an ingot enters the Forge
Shop stock area until the delivery note is issued and the
forged products leaving the Forge Shop. Specifically, all
handling during heating, forging and release procedures
are documented with regard to a single piece tracing. This
finger print of forgings being processed in the new Forge
Shop provides the highest transparency of production history of material. Finally, it provides an automatic forging
report with all relevant data stored in the forge shop data
base.
An automatic internal quality release is provided within
the PRINS system, including automatic issuing of non conformance reports in case of deviation between set point
and actual process data. PRINS also checks between SAP
and SLS whether the data set for issuing an internal forging order is defined completely. This guarantees that no
orders enter the shop floor level unless all necessary production parameters are determined and standardized.
The data documentation and material tracing is in full
compliance with all requirements for production of Superalloys e.g. for aerospace applications.
Auxiliary Systems
With the new production unit on line FEM-Software is
being implemented in order to investigate opne die forging processes on the theoretical level for development
purposes as well as for evaluating process borderlines of
existing forging practices. Prediction of grain size distribution and development during conversion is an important
part of the future investigation. The software is applied in
the central R&D department of ThyssenKrupp VDM GmbH
and in the process development at the forge shop, where
an engineer is fully occupied on forging issues.
In September 2008 the implementation of an inline
Laser Measurement System took place. The system has
been adapted to the special demands of ThyssenKrupp
VDM GmbH in terms of scan velocity, tolerance accuracy
and bite shift optimization features. This development focuses on providing as much assistance as possible to the
press operator for optimizing the forging passes in terms
of homogeneity of the forgings. Furthermore this system
provides additional process data for the data documentation and process control e.g. complete thermal scans
of the intermediate or final forgings and geometry data.
Together with the described Order Management Systems,
the FEM software and a Pass Scheduling software the new
forge shop is having the most modern IT-tools at its disposal.
Staff qualification
A very important aspect has been the qualification plan
for the forge shop crew. Most of the employees engaged
in the Forge Shop had no forging experience or hot conversion experience at all and were previously working in
cold finishing departments of ThyssenKrupp VDM GmbH.
Together with the few newly hired employees with press
11.
Technical key data of the furnaces
Technische Daten der Wärmöfen
forge experience the whole crew started a 4 month qualification period in October 2007. By January 2008 they
were trained in the theory of deformation technology, machine design, function of forging presses, manipulators
and heating furnaces. Knowledge on material technology
of Nickel Alloys, test lab activities and occupational safety
issues were also imparted.
The crew spent most of the four month time on internships in forging mills and finishing departments for billets
and bars. Forging internships were conducted at the open
die forge shops of Deutsche Edelstahlwerke GmbH in Krefeld, Germany and Società delle Fucine s.r.l. in Terni, Italy,
a company of ThyssenKrupp Acciai Speciali Terni.
As a matter of fact from the very beginning this extensive qualification program has been the foundation on
which the successful operation of the new forging line was
based upon.
Ramp-up curve and first results
After completion of the main machine optimization the
internal product qualification of Nickel Alloy forgings started on the 20th of March 2008. In a three month period
until the end of June, a program was conducted which
covered almost 90 % of the ThyssenKrupp VDM GmbH
forged products range. During this program more than
400 t of Nickel Alloys were forged and tested according
customer specification to assure that all new designed
forging recipes were capable of producing material in accordance with specification demands. Almost all forging
procedures delivered successful repeatable results on final products according customer specifications from the
very beginning. As a result about four months earlier than
originally scheduled significant reduction of external conversion to in house forging in the new Forge Shop could
be accomplished. In the same way, conversion for other
companies started much earlier than planned already in
May 2008 with first forgings for ThyssenKrupp Titanium
GmbH in alloy TiAl6V4 directly followed by first conversion
for Deutsche Edelstahlwerke GmbH in low alloyed carbon
steel grades. The amount of toll forging activities for both
of these companies and others as well increased significantly during the past months since May.
12.
52 t ingot carbon steel before forging
52 t Block vor dem Schmieden
13.
17 t forging in Nicrofer 5520Co for power plant application
17 t Schmiedeteil aus Nicrofer 5520Co für neue Kraftwerksentwicklung
14.
Nicrofer 5219Nb AMS
premium qualitty in as
forged condition
Nicrofer 5213nB AMS
für rotierende Turbinenteile in geschmiedetem
Zustand
Figure 12 shows a 52 t ingot carbpon steel before forging.
Beyond these important results during the first months
of operation, the heaviest ESR ingot with a diameter of
about 1 m has been successfully forged to a forging of
about 17 t weight ready to be processed in further tube
manufacturing for a the new 700 °C power plant project,
figure 13.
First premium quality forgings of Nicrofer 5219Nb AMS
from triple melt ingots (VIDP-ESR-VAR) were forged including upsetting according a special designed forging schedule for 8” inch final size, figure 14. All results were in
full compliance with the related specifications for rotating
parts in jet engines. The grain size distribution was homogeneously at about ASTM 8,5 across the billet cross
section in the as forged condition.
Conclusion
ThyssenKrupp VDM GmbH together with all its suppliers
succeeded in on time commissioning of the new Forge
Shop. All objectives defined during the early project phase
were achieved. The time schedules were even reduced,
exceeding expectations. This was an important issue as
it enables the earlier than planned reduction of external
conversion and the earlier start of contract conversion for
other companies.
The forging schedules developed during the first press
utilization were focussed on establishing a stable quality level on forged products as quickly as possible. Since
August 2008 the forging schedules are being gradually
optimized in order to increase the productivity on the new
forging line to the target levels. This is being supported
by FEM calculations and growing experience of in-house
forging.
With the first forgings of Nicrofer 5219Nb, AMS premium quality in June 2008, ThyssenKrupp VDM GmbH proved that know how, procedures and process capability are
available for the entire production line, including in-house
forging of premium quality billets for rotating parts in aircraft turbines. This confirms the Forge Shop investment
decision to be fully aligned to the ThyssenKrupp VDM
GmbH growth strategy.
hans-peter.jeager@thyssenkrupp.com