(1) It can overcome the resistance of the mold and the secondary cooling device to the casting billet, pull the cast billet out, and send the ingot bar into the lower mouth of the mold.
(2) The pulling speed can be adjusted to meet the different requirements of different steel grades and different casting slab sections for the pulling speed, and a faster speed is required when the ingot bar is lifted.
(3) There must be enough opening between the upper and lower rollers of the pull-straightening roller and can be adjusted to produce cast billets with different cross-sections. When a rigid inser is used, the inser shall be allowed to pass.
(4) The upper roll should have sufficient reduction force to meet the requirements of the drawing friction and straightening of the cast slab. The pressure must be adjustable to meet the requirements of different sections. It is necessary to prevent the casting billet from being excessively pressurized to cause defects in the cast billet, and the pressure should be changed rapidly when the ingot bar is transitioned to the billet when pouring is started, so as to prevent the high-temperature cast billet from being compressed and deformed.
Recently, with the development of high-efficiency continuous casting technology, many casting machines have adopted multi-point straightening technology. Due to the high drawing speed in high-efficiency continuous casting, the length of the liquid core of the cast slab is very long, and it needs to be straightened with liquid core. During liquid phase straightening, the strength and allowable deformation rate of the shell of the cast slab at the interface of the two-phase zone are extremely low. The use of multi-point straightening can disperse the strain concentrated at one point to multiple points to complete, control the straightening deformation rate within the allowable range, and prevent the possibility of internal cracking in the slab.