TY - JOUR

T1 - Role of Solidification in Submerged Entry Nozzle Clogging During Continuous Casting of Steel

AU - Barati, Hadi

AU - Wu, Menghuai

AU - Kharicha, Abdellah

AU - Ludwig, Andreas

PY - 2020/7/16

Y1 - 2020/7/16

N2 - Metallurgists are embroiled in a debate on the role of solidification in submerged entry nozzle (SEN) clogging during continuous casting of steel: does clogging originate from solidification, or does clogging cause the solidification? This study tries to clarify this debate. An enthalpy-based mixture continuum model is used to simulate solidification in a clog structure. The 3D structure of the clog is reconstructed using X-ray tomography images of an as-clogged piece in an SEN, and is directly used in the numerical model. The flow and solidification in the open pores/channels of the clog structure are then calculated. The modeling results demonstrate that although solidification does occur deep in the clog structure as the melt flow is stopped, a gap remains between the solidification and clog fronts. This gap signifies an open-channel clog region, and the clog structure in this region needs to be mechanically strong to withstand the impact of the melt flow; otherwise, fragmentation occurs. The study verifies that the solidification cannot occur before clogging if the molten steel has sufficient superheat and the SEN is properly preheated. A SEN made of an isolating refractory material can postpone the clogging, thereby extending its service life.

AB - Metallurgists are embroiled in a debate on the role of solidification in submerged entry nozzle (SEN) clogging during continuous casting of steel: does clogging originate from solidification, or does clogging cause the solidification? This study tries to clarify this debate. An enthalpy-based mixture continuum model is used to simulate solidification in a clog structure. The 3D structure of the clog is reconstructed using X-ray tomography images of an as-clogged piece in an SEN, and is directly used in the numerical model. The flow and solidification in the open pores/channels of the clog structure are then calculated. The modeling results demonstrate that although solidification does occur deep in the clog structure as the melt flow is stopped, a gap remains between the solidification and clog fronts. This gap signifies an open-channel clog region, and the clog structure in this region needs to be mechanically strong to withstand the impact of the melt flow; otherwise, fragmentation occurs. The study verifies that the solidification cannot occur before clogging if the molten steel has sufficient superheat and the SEN is properly preheated. A SEN made of an isolating refractory material can postpone the clogging, thereby extending its service life.

KW - clogging

KW - continuous castings

KW - solidification

KW - steel castings

UR - http://www.scopus.com/inward/record.url?scp=85088783940&partnerID=8YFLogxK

U2 - 10.1002/srin.202000230

DO - 10.1002/srin.202000230

M3 - Article

VL - 91.2020

JO - Steel research international

JF - Steel research international

SN - 0177-4832

IS - 12

M1 - 2000230

ER -