What are the process requirements of the bright annealing furnace

Process requirements of bright annealing furnace

If the bright annealing furnace wants to improve the quality of the produced products, it needs to meet some specified process requirements:

　　1. heat transfer

　　The heat transfer conditions in the annealing space will directly affect the output of the bright annealing furnace. In fact, after the steel plate reaches the specified annealing temperature, the required metallographic transformation can be completed after less than 1 minute of heat preservation, and the heating and cooling speed allowed by the process are far greater than the value that the coil heat transfer conditions can achieve. Therefore, enhancing heat transfer means shortening the heating and cooling time and increasing the output.

　　2. protective gas

　　In order to obtain a bright cold-rolled sheet surface, annealing should be carried out in a protective atmosphere. Generally use nitrogen, nitrogen-hydrogen mixture or hydrogen as the protective gas for the bright annealing furnace. The increase in hydrogen content helps to improve the reducibility of the atmosphere and prevents oxidation of the cold-rolled sheet.

　　 Lowering the protective gas dew point also plays an important role in preventing oxidation and decarburization. The residual rolling emulsion on the surface of the coil must be effectively removed during the annealing process, otherwise carbon deposits will be generated on the surface of the cold-rolled sheet, which will affect the surface quality of the cold-rolled sheet.

　　 3. Consumption cost

Reducing consumption means lowering the operating cost of the bright annealing furnace. Efforts should be made to reduce consumption indicators under the premise of ensuring product quality and output. The consumption on the bell-type furnace mainly includes heating (fuel or electricity), electricity for fan drive, protective gas and cooling water.