6.7　Secondary Cooling and Strand Guide Equipment

6.7.1　The secondary cooling and strand guiding unit of billet caster shall be designed according the guiding of dummy bay and strand without clamping of strand，and the structural design shall be simple.The numbers of guide roll at inner bow can be less than that of outer bow，and the lateral guiding unit shall be installed.

6.7.2　For the billet caster with adoption of rigid dummy bar，the first strand guiding segment can be provided with water spray pipe instead of guide roll.

6.7.3　For the bloom caster with adoption of flexible dummy bar，the first strand guiding segment can be movable guiding segment and the containment segment in certain length shall be provided according to the conditions such as caster radius，steel grade，casting section and casting speed.

6.7.4　The secondary water spray pipe of square billet caster and round billet caster shall supply the water section by section，and the design with longitudinal pipe arrangement shall be adopted.

6.7.5　Roll geometrical arrangement of strand secondary cooling and guiding segment in slab caster requires the roll geometry calculation.The caster shall adopt the compact roll arrangement with small roll diameter，and the split roll may be used as the case required.

6.7.6　The strand guiding unit of slab caster preferably uses segment combined method.The segment shall be designed for interchangeability and shall be ensured for easy installation and dismantling as well as good rigidity and alignment.

6.7.7　The segment of slab caster preferably adopts the structure with clamping by hydraulic cylinder.The dynamic soft reduction technology can be used at the solidification end of strand in case of necessary.

6.7.8　The maintenance device of segments of slab caster shall be determined according to the specific conditions of workshop and the principle of easy replacement，the longitudinal replacement at inner bow is preferably used.

6.7.9　The secondary cooling chamber of slab caster shall adopt the tunnel type sealing design.

6.7.10　Segment 1and segment 2 of beam blank caster shall adopt the containment mechanism with compact roll in small diameter.The strand bulging and bulging strain shall be strictly controlled.The secondary cooling segment shall be equipped with cooling water suction and purging system.

6.7.11　Top roll containment mechanism shall be provided under the mould of beam blank caster，and the containment and guiding of beam blank shall be performed.

6.7.12　Roll and bearing of strand guiding segment of slab caster shall be cooled internally with water.

6.7.13　Maximum opening of strand guiding segment of slab caster shall be determined according to the conditions that the solidified strand which cannot be straightened can still be withdrawn after cutting into several pieces.

6.7.14　Secondary cooling of strand guiding segment of slab caster can adopt the distributed cooling control as per strand width.