Improvement of Hydraulic Oscillation Control System of Continuous Casting Machine
It is a new skill to complete the transformation of a high-quality and high-yield continuous caster by simply transforming the general level continuous caster to complete 400 hydraulic oscillations, the deflection rate reaches 50%, and can be adjusted online. When the instantaneous rise of bus voltage is monitored, the frequency converter will appropriately increase the output frequency to reduce the regenerative energy causing the rise of bus voltage, which reduces the possibility of inverter overvoltage fault.
The hydraulic oscillation control system of the horizontal continuous casting machine has been tested 6 million times in succession. The test data meet the actual production needs, and the equipment is intact. Because the equipment adopts a reliable sealing structure design, not only will there be no leakage, but also the sealing life is greatly improved, which makes the operation cost of the system far lower than that of the mechanical oscillation system.
The high-temperature molten steel is continuously poured into one or a group of water-cooled copper crystallizers, and the molten steel is gradually solidified into a billet shell along the periphery of the crystallizer. After the steel liquid level rises to a certain height and the billet shell solidifies to a certain thickness, the tension leveler pulls out the billet, and the billet is cooled by water spraying in the secondary cooling area to completely solidify the billet. The cutting device cuts the billet to a specified length according to the steel rolling requirements.
There is a liquid slag film between the primary shell and the mold wall. The conflict here is vicious conflict, that is, the magnitude of the conflict force is proportional to the relative motion speed, and the viscosity of the slag film is inversely proportional to the thickness of the slag film. In this way, during the oscillation positive slippage of the mold of the horizontal continuous caster, this conflict force and the resulting tensile stress on the billet shell are large, which may crack the primary billet shell. Therefore, a non-sinusoidal oscillation skill is developed to reduce this conflict force.
Theoretical research and simulation experiments show that proper selection of non-sinusoidal oscillation parameters can reduce the conflict force by 50 ~ 60%. However, if the mold is smooth and poor, the green shell is bonded with the copper wall; The liquid level of the mold shakes too much, and the insoluble matter in the slag is rolled into the condensate shell. In this way, there is a transverse discontinuity on the surface of the slab, with significant traces of incomplete welding.
The horizontal continuous caster is composed of molten steel carrier, tundish and its replacement device, mold and its vibration device, secondary cooling zone clamping roller and cooling water system, pull straightener, cutting equipment, ingot drawing device, etc.