FIELD: metallurgy, namely steel continuous casting. SUBSTANCE: apparatus includes builtup crystallizer having four combined in pairs lengthwise walls. Each wall of first pair is widened by angle γ relative to vertical line, it has upper and vertical lower portions and secured to two eccentric mutually parallel horizontal shafts provided with synchronous rotation drive unit. Each wall of second pair is made on drive shaft with possibility of phase-shift reciprocation motion relative to said first pair of walls. Said drive shaft has three portions along its length. Two terminal portions of said shaft provide rotation of eccentric relative to mean potion of said shaft by 90 degrees. According to invention said terminal portions of drive eccentric shaft provide rotation of eccentric relative to mean portion by angle β =90 degrees - γ. In addition changeable cover plates are placed onto inner surface of each wall of first pair, they have portion enlarged relative to vertical line by angle γ and lower vertical portion. Insert made of other material is arranged in addition onto vertical lower portion of said changeable cover plate. Ratio of heat conductivity factor λ1 of material of said cover plate in its enlarged upper portion and such factor λ2 of insert material λ1/λ2 is equal to 2-2,5. EFFECT: enhanced reliability of crystallizer operation and high quality of billet surface. 3 cl, 4 dwg
