4.5　Processing Equipment

4.5.1　The continuous casting slabs shall be cut to length with a flame cutting torch，and the surface shall be cleaned with a flame cleaning device or other devices.The cut-to-length machine shall be combined with the feeding/laying-off equipment，conveying and centering equipment，weighing and mark sprayprinting device into a combined unit.

4.5.2　The slabs should be heated in a walking beam furnace；the slabs of special steel grade and slabs in special specifications can be heated in a pusher-type reheating furnace，external mechanized chamber furnace，or bogie hearth furnace.The reheating furnace shall be equipped with a heat recovery device.A walking beam reheating furnace or pusher-type reheating furnace should employ an evaporative cooling device.

4.5.3　A descaling box shall be arranged in front of the roughing mill，and shall be provided with sophisticated safety protection devices.A descaling water header shall be arranged at the entry side and exit side of the rolling mill.The outlet pressure of the nozzle of the descaling device shall not be lower than 18MPa.

4.5.4　The rolling mill shall be a four-roll reversing one，and shall meet the following requirements:

1　The mechanical parameters of the rolling mill shall meet the requirements of control rolling.

2　The rigidity coefficient of the rolling mill shall not be lower than 8，000kN/mm.

3　The finishing mill shall be provided with an electric screw-down and hydraulic automatic gauge control（AGC）system；the roughing mill that is used to directly produce finished steel plates shall also be provided with a hydraulic automatic gauge control（AGC）system.

4　The finishing mill shall be provided with a profile control system.

5　The horizontal rolling mill shall be provided with a quick roll changing device.

6　The edging mill shall be arranged near the roughing mill.

7　The rolling mill should be provided with entry and exit smoke and dust suppression devices.

4.5.5　The accelerated control cooling unit shall have high cooling capacity and a wide cooling speed range for accelerated control cooling of rolled steel plate（or have a direct quenching means），and shall be able to regulate and control the cooling water flow automatically and accurately.

4.5.6　The hot straightening machine should be a fully hydraulic quadruple reversing unit with 9-11 rolls，to meet the requirement for low-temperature straightening of steel plate during control rolling and control cooling operation；in addition，the hot straightening machine shall have straightening roll prebending，entire roll system tilling，and separate entry/exit roll gap adjusting functions，and shall be provided with overload protection devices and quick roll system changing unit，etc.

4.5.7　The cooling bed should be of walking beam type or rolling disk type；the separate cooling bed for steel plates in thickness greater than 50mm can be of grate-chain type or walking beam type.

4.5.8　A ultrasonic flaw detection device should be used for online flaw detection of the steel plate，and the device shall be able to carry out automatic and continuous flaw detection along the surface of the entire plate.Alternatively，offline automatic flaw detection or manual flaw detection can be used for the steel plate.

4.5.9　Cropping and dividing shears，double-side trimming shears，and dividing shears shall be provided for shearing the steel plate；a slitting shears should be provided for a 5，000mm wide plate rolling mill and should be arranged near the double-side trimming shears.The dividing shears，double-side trimming shears，slitting shears，and sizing shears should be of rolling cut type.For a medium slab rolling plant with annual yield lower than 100×104t/a，a disk shears can be used for trimming steel plates in thickness not greater than 25mm.

4.5.10　Samples of the steel plate should be taken at the dividing shears；samples of a steel plate in thickness greater than 50mm can be taken by cutting with an offline cutting device.

4.5.11　The shearing line shall be equipped with top and bottom surface inspection and regrinding equipment for the steel plates，automatic steel plate scribing and centering equipment in front of the shearing machine，plate head/tail，clipping and sample conveying and collecting equipment，and finished steel plate inspection and mark printing devices.

4.5.12　The cold straightening machine should be a fully hydraulic quadruple reversing unit with 9-11 rolls，shall have straightening roll pre-bending，entire roll system tilting，and separate entry/exit roll gap adjusting functions，and shall be provided with overload protection devices and quick roll system changing unit，etc.

4.5.13　A shot-blasting machine shall be used if surface treatment is required for the steel plate.

4.5.14　The heat treatment furnace can be of flame heated roller hearth type，radiant tube heated nonoxidizing roller hearth type，or flame heated double walking beam type；the quenching machine should be a roller-type quenching machine.For heat treatment of steel plates in a small lot，of a special steel grade，or in special specifications，a non-continuous heat treatment furnace should be used.