The feeding tips and nozzle provide the casting and rolling zone with a uniform, stable and continuous molten aluminum in the width direction of the plate, which is a prerequisite for the smooth progress of rapid continuous casting and rolling. Before the 1970s, the casting-rolling speed of the casting-rolling mill was low, the quality of casting-rolling was not high, and the requirements for the nozzle were not high, and the design of the nozzle cavity was mostly based on experience design. Existing casting and rolling mills have different nozzle structures, and the flow state of the nozzles in production is a major factor restricting normal production. Therefore, the research of casting tips and nozzles has become a hot spot of people’s research.
In the double-roll continuous casting and rolling process, the feeding tips and nozzle structures have an important influence on the stable process and the improvement of the quality of the cast slab. The casting tip and nozzle structure with uniform flow distribution is an important guarantee for obtaining high-quality aluminum alloy slabs. In the actual production process, the wider the plate, the wider the nozzle structure required, the more difficult it is to make the fluid velocity distribution at the nozzle outlet uniform, and it may even cause the casting-rolling process to fail smoothly.
The uniformity of fluid velocity distribution improves as the length of the nozzle increases. When the length of the nozzle is greater than 400 mm, the change in length has less influence on the uniformity of the fluid velocity distribution at the nozzle outlet.
The preparation method of the casting nozzle material for aluminum deep processing is to first prepare the casting nozzle material, and then apply a non-stick aluminum coating to the surface of the casting nozzle material by brushing, so that the surface of the casting nozzle material has a non-stick aluminum coating. After nitriding treatment, the nozzle material is combined with the non-stick aluminum coating to form a composite structural material with a non-stick aluminum coating on the surface. The non-stick aluminum coating is a composite coating of silicon nitride and boron nitride. This increases the service life of the casting nozzle material, and can be used repeatedly without damage, improves the production efficiency and continuous operation time, and reduces the cost.