Hot-dip galvanized steel strip section precision control heat treatment process and its alloying furnace

Abstract

The invention discloses a hot-dip galvanized strip steel subsection precision-controlled heat treatment process and an alloying furnace thereof. This process is to heat, heat-preserve, and cool the strip steel output from the zinc pot in sequence, and finally realize the alloying process of the strip steel. The high-temperature gas screen in the direction of steel conveying, and the temperature signal in each partition formed by the high-temperature gas screen is transmitted to the central control PLC processor in time, so that the central control PLC processor can control the injection of the high-temperature gas screen in each partition in real time speed, air barrier temperature, and resistance heater power to precisely control the holding temperature in each compartment. Its alloying furnace includes a bottom heating section, a middle heat preservation section and an upper cooling section. The key point of the design is to install sealed air knife generators at the outlets of the three partition sections of the middle heat preservation section. The invention can suppress the occurrence of "chimney effect", reduce heat dissipation in the heat preservation section, and improve heat treatment efficiency.

Description

technical field [0001] The invention relates to the field of hot-dip galvanized strip steel manufacturing, in particular to a hot-dip galvanized strip steel subsection precision-controlled heat treatment process and an alloying furnace thereof. Background technique [0002] Due to its low production cost, good corrosion resistance, coating performance, welding performance and impact resistance, hot-dip galvanized steel sheet is very suitable for high-end hot-dip galvanized product consumption industries such as automobiles and home appliances, and can meet the needs of users. The quality requirements of high-quality surface characteristics and good internal performance of products. [0003] The hot-dip galvanized steel strip output from the zinc pot usually needs to complete multi-stage heat treatment in the alloying furnace. The internationally accepted process is the annealing process of "first high temperature and then low temperature". There is also a slight difference ...

AI Technical Summary

Problems solved by technology

However, due to the lack of effective separation of the central heat preservation section, the resistance heaters in each section adopt open-loop control and are heated according to the predetermined temperature. The coupling effect of the thermal field between different sections makes it difficult to accurately control the amount of heat released. Abnormalities are prone to occur, and there is great uncertainty in the insulation effect, resulting in fluctuations in alloying properties

Moreover, there is a large heat loss between the movable insulation section and the fixed insulation section, and the outlet temperature of the fixed insulation section is still high due to the "chimney effect", which has a relatively large adverse effect on the equipment in the subsequent upper cooling section, resulting in cooling capacity. Seriously insufficient

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