Tube Billet Heating Defects and Its Prevention

Hot-rolled seamless steel pipe products generally require two heating, which perforated pipe in the heating and rolling of the pipe diameter after a given pre-heating; production of cold rolling (pulling) when the pipe requires an intermediate annealing to eliminate residual stress Use; For some special requirements of the steel, in order to improve the mechanical properties of steel and improve the organization and process performance, and heat treatment. Common tube (tube) heating tube defects uneven heating, oxidation, decarburization, overheating, overheating heating cracks.


Pre-heated perforated pipe, the purpose is to improve the ductility, reduce the deformation resistance of steel; to provide a good metallurgical structure. Toroidal furnace tube, furnace, tilting hearth furnace and trolley furnace. Aiming at the problem of insufficient pipe diameter before reheating, it is proposed to improve the temperature and uniformity of the steel pipe, improve the ductility of the steel, control its microstructure, create favorable conditions for the sizing of the base metal and the mechanical properties of the steel. Ordinary furnace step furnace, continuous roller hearth furnace, furnace tilt, induction heating furnace. Cold-rolled (pull) heating quenching is to eliminate and reduce the deformation resistance. Ordinary annealing furnace is mainly used for heating furnace, trolley furnace, continuous roller hearth furnace. In the seamless steel pipe production, toroidal furnace and heating furnace is the most widely used electric furnace, is also developing electric furnace, tilting furnace because of poor quality, labor-intensive, easy to eliminate. Continuous roller hearth furnace is mainly used for heat treatment of cold rolled (drawn) steel; suitable for small batch trolley furnace, heat treatment and heat preservation of thick walled alloy steel pipe longer heat treatment time; Surface heat treatment and cold working steel annealing without oxidation (pull) pickling process.