Vallourec and Mannesmann Deutschland GmbH

Düsseldorf, Germany

Vallourec and Mannesmann Deutschland GmbH

Düsseldorf, Germany

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Jahn A.,Vallourec and Mannesmann Deutschland GmbH | Steinhoff K.-P.,Huttenwerke Krupp Mannesmann GmbH | Dubberstein T.,TU Bergakademie Freiberg | Franke P.,Karlsruhe Institute of Technology | And 9 more authors.
Steel Research International | Year: 2014

In the present work the influence of phosphor on the flowability, the effect on the infiltration of ZrO2 open foam ceramics and the martensite formation as well as the resulting mechanical properties of high alloyed CrMnNi as-cast steels is studied. Additionally, the effect of phosphor on surface tension is investigated. The study is performed using thermodynamic calculations, static tensile tests, notch-bar impact tests, optical light microscopy, scanning electron microscopy, energy dispersive X-ray analysis, electron backscatter diffraction, and the magnetic scale for the detection of ferromagnetic phase fractions. Maximum bubble pressure method is used to measure the surface tension of the liquid steel. The martensite phase fraction is not significantly influenced with increasing phosphor content. The flowability and the quality of the infiltration of open foam ceramics are improved with increasing phosphor contents. The investigated specimens show an increasing yield and an ultimate tensile strength with higher phosphor contents. The uniform and the fracture elongation as well as the notch impact resistance remain at high values. Moreover, an increase in phosphor content did not significantly change the surface tension of the investigated CrMnNi alloys. The influence of increasing phosphor content on the flowability, the effect on the infiltration of ZrO 2 open foam ceramics, the martensite formation as well as the resulting mechanical properties and the surface tension of high alloyed CrMnNi as-cast steels are studied. The elongation properties are not influenced by increasing phosphor content. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Dubberstein T.,Institute of Iron and Steel Technology | Jahn A.,Vallourec and Mannesmann Deutschland GmbH | Lange M.,ArcelorMittal | Heller H.-P.,Institute of Iron and Steel Technology | Scheller P.R.,TU Bergakademie Freiberg
Steel Research International | Year: 2014

The effect of temperature, atmosphere, and elemental concentrations of boron and phosphorous in ferrous alloys on the wettability of polycrystalline α-Al2O3 was studied. The investigation of the wetting behavior is of major importance to the infiltration of steel into open foam ceramics. In reference Fe-0.46 wt% C iron samples, the contact angle was investigated between 1550 and 1650 °C under Ar-H2 and Ar atmospheres and was found to decrease with increasing temperature and increasing oxygen partial pressure. Furthermore, no FeAl2O4 (hercynite) spinel type inclusions were found in Fe/Al2O3 experiments. In the Fe-P binary alloys, θ decreased with increasing phosphorous content and was ≈112° for the Fe-0.299 wt% P alloy at 1600 °C. For the Fe-B binary alloys, a strong influence of boron on the contact angle was found. Secondary neutral mass spectrometry (SNMS) analysis showed a maximum in the boron concentration in the first 50 nm of the metallic side of the interface. In the FeCrMnNi-P high-alloys specimens, a reaction layer was found between the steel/ceramic interfaces. The contact angle was ca. 90°, lower than the Fe-P binary alloys. The effect of temperature, atmosphere, and the elemental concentrations of boron and phosphorous in iron and CrMnNi steel on the wettability of polycrystalline α-Al2O3 has been studied. The contact angle of TRIP/TWIP as-cast steel on alumina substrates decreases with an increased phosphorous content. The findings are of major importance for a better infiltration efficiency of open foam ceramics. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Geiler D.,Salzgitter Mannesmann Forschung GmbH | Deppe G.-J.,Salzgitter Mannesmann Forschung GmbH | Helten B.,Vallourec and Mannesmann Deutschland GmbH
Stahl und Eisen | Year: 2012

In a plug mill for seamless tubes the sizer at the end of the rolling line essentially defines the dimensions of the tubes. In the plug mill of Vallourec Et Mannesmann Tubes Germany at Düsseldorf-Rath the sizer consists of ten stands, in each of which the right cage out of a stock of about 400 has to be inserted. This mapping arises from the specifications of the rolling lot. By applying an adapted RFID (Radio Frequency Identification) system an improved loading of the stands with cages could be achieved. Sequentially the actual status of allocation is automatically logged and checked with the demands for the respective rolling lot.


Fuchs R.,Bohler Welding Group United States Inc. | Heuser H.,Bohler Schweisstechnik Deutschland GmbH | Hahn B.,Vallourec and Mannesmann Deutschland GmbH
Materials at High Temperatures | Year: 2010

In fossil fuel fired power plants, appropriate materials are required which correspond to the different temperature and oxidizing conditions in the boiler and in the super-heater sections. Pipe steels with 2 1/4 Cr (T/P22; T/P23; T/P24) must be welded with 9-12%Cr steels (T/P91; T/P92). In this area, the choice of the appropriate welding filler material is decisive for the quality of the connection. This report highlights the possibilities for achieving optimal qualities in different dissimilar metal welds under conditions of reduced carbon diffusion. © 2010 Science Reviews 2000 Ltd.


Knezevic V.,Vallourec and Mannesmann Deutschland GmbH | Schneider A.,Vallourec and Mannesmann Deutschland GmbH | Landier C.,7 Avenue du General Leclerc
Procedia Engineering | Year: 2013

The need for higher steam temperatures in the future high efficiency coal-based power plants (Advanced Ultra Super Critical (A-USC) power plants) has modified the customers' materials requirements. At the steam temperatures up to 730°C Ni-base alloys are needed for the construction of the critical components capable of operating under these more severe conditions. Additionally, the very high pressures lead to very thick steam piping connected to the steam turbine. These are very challenging tasks for both, the manufacturing technology and the material performance assurance, as the currently available data are mainly for thin walled components of gas turbines and the chemical industry. Vallourec & Mannesmann Tubes is since 1999 involved in several German and European projects concerning thick-walled Alloy 617 pipes for 700°C power plant technology. The seamless pipes, manufactured using Ehrhardt press and Pilger process, were subject of extensive microstructural and mechanical investigations, including creep testing, as a part of qualification program. The material is tested in two conditions, as-delivered solution-annealed and after stabilization heat treatment. Creep testing programs for both conditions up to now include 108 testing specimens and a testing time period of 825 000h in total. The results and creep performance, which is in excellent agreement with the existing results for Alloy 617, are going to be presented and discussed. © 2013 The Authors.


Arrar M.J.,Valllourec and Mannesmann Deutschland GmbH | Gevelmann G.,Vallourec and Mannesmann Deutschland GmbH | Heuser H.,Bohler Schweisstechnik Deutschland GmbH | Tak K.G.,Bohler Schweisstechnik Deutschland GmbH
Advances in Materials Technology for Fossil Power Plants - Proceedings from the 7th International Conference | Year: 2014

On the following pages this paper reflects on the idea, the demand requirements, the development and qualifications of a bainitic- martensitic steel grade and matching welding consumable for Power Plants with steam conditions of ultra super critical nature (605/625°C and 300/ 80bar). Furthermore it helps to understand recent events and gives options/possibilities for the handling of grade T24 from a tubular components and a welding consumables manufacturer's point of view. The paper consist of three main chapters • Chapter I: Development and qualification of the base material (Jarrar/Gevelmann) • Chapter II: Development, qualification and recommendations for the welding consumables (Heuser/Tak) • Chapter III: Experiences during manufacturing and erection including conclusions (Gevelmann/ Jarrar) Copyright © 2014 Electric Power Research Institute, Inc. Distributed by ASM International®. All rights reserved.


Kovalev A.,TU Bergakademie Freiberg | Wendler M.,TU Bergakademie Freiberg | Jahn A.,Vallourec and Mannesmann Deutschland GmbH | Weiss A.,TU Bergakademie Freiberg | Biermann H.,TU Bergakademie Freiberg
Advanced Engineering Materials | Year: 2013

The microstructure evolution during deformation and the mechanical behavior of an austenitic Cr-Mn-Ni as cast steel are investigated at various temperatures. The deformation-induced twinning and Ïμ/α′- martensite formation - the TWIP and TRIP effects - occur in the investigate steel depending on the deformation temperature. For characterization and illustration of the TRIP/TWIP effects the STT and DTT diagrams are developed. Finally, the α′-martensite nucleation threshold is determined, and an equation is proposed to describe the volume fraction of strain-induced α′-martensite as a function of the total driving force. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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