During 1999 and 2000, the six lines of the continuous billet casting machine of ISPAT Unimetal at Gandrange (France) have been equipped with the DIAMOLD moulds developed by VOEST- ALPINE Industrieanlagenbau (VAI). This transformation required no constructional change of the machine and represented only a minimum investment. The new mould technology allows to cast at very high speeds (above 3 m/min) and to comply with all quality requirements for a wide range of steel grades.