Construction of moolbs used for the continuous

Claim 1

A CONTINUOUS CASTING MOULD WHICH COMPRISES FOUR MOULD PLATES OF RECTANGULAR PROFILE HELD IN CONTACT AT THEIR EDGES TO FORM AN OPEN-ENDED MOULD SPACE OF RECTANGULAR CROSS-SECTION THE MOULD PLATES BEING RIGIDLY SECURED TO RIGID EXTERNAL BACKING PLATES AND WATER-COOLING PASSAGES BEING FORMED BETWEEN THE MOULD PLATES AND THEIR ASSOCIATED BACKING PLATES, AND IN WHICH THE MARGINAL PORTIONS OF EACH OF AT LEAST ONE PAIR OF OPPOSITE MOULD PLATES LOCATED ADJACENT OT THE CORNERS OF THE MOULD AND OUTSIDE THE CONNECTIONS OF THE MOULD PLATE TO ITS BACKING PLATE ARE RELIEVED ON THEIR REAR SURFACES IN SHUC A WAY AS TO INCREASE THE LATERAL FLEXIBILITY OF THE SAID MARGINAL PORTIONS UNDER LATERAL STRESSES IMPOSED BY THERMAL EXPANSION OF THE ADJACENT MOULD PLATES IN CONTACT WITH THEM, AND CLEARANCES ARE PROVIDED BETWEEN THE RELIEVED MARGINAL PORTIONS AND THE ASSOCIATED BACKING PLATES.