In recent years "Dillinger Huette" developed a manufacturing technology of corrosion resistant alloys (CRA) clad plates for pipelines transporting oil and gas containing H_2S, CO_2 and other chemicals by the application of the so called "TMCP-clad process". The use of this TMCP-clad process allows to produce clad plates with an excellent property profile over plate thickness including CRA-layer, bonding line and base material. The bounding properties are mainly influenced by the slab assembling technology (as described in the paper), the reheating conditions and finally by the rolling process parameters. The specified corrosion resistance of the CRA layer is already achieved in the as-rolled condition by the application of a modified thermomechanical control process, which is especially designed for the clad plates. In order to obtain extended corrosion resistance in the CRA layer especially pitting resistance (ASTM G48) it is necessary to suppress the precipitation of chromium carbides by adequate finish rolling temperatures. Consequently the TMCP-clad process is characterised by adapted finish volling temperatures in combination with an accelerated cooling (ACC) with water. For the base material conventional microalloyed Nb-V or Nb-Ti steels can be used. By optimisation the rolling and cooling conditions, the TMCP-clad process leads to properties in the base material up to X65 according API 5L specification combined with excellent low temperature toughness and even eminent HIC resistance with a significant low carbon-equivalent of about 0.30. In the paper the TMCP-clad process is described and examples are given.
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