Most of the oil pipelines of petrochemical plants are pipelines that transport high temperature, high pressure and corrosive media. In the working process, the medium transported by the oil pipeline has certain corrosivity, so the toughness and corrosion resistance of the pipe must be improved. In order to meet the requirements of pipeline work, the heat treatment manufacturer adopts the pipeline post weld heat treatment production line for heat treatment, and the effect is good.
1、 Heat treatment process flow of process pipeline
Manual feeding track conveying induction heating quenching spray cooling quenching track conveying induction tempering track conveying blanking rack stacking
2、 Heat treatment process
1. The function of medium frequency induction heat treatment equipment is to improve the material toughness and corrosion resistance of the pipeline and give full play to the strength and toughness of the material. Generally speaking, the purpose of quenching and tempering heat treatment of alloy steel is to ensure that the pipeline has sufficient strength, toughness and corrosion resistance. The heat treatment process adopts medium frequency induction heating equipment for heat treatment. The heating and quenching temperature is within 900, the water cooling and tempering temperature is within 650 to 700, and then cooled to 480 for thermal correction.
2 . The heat treatment temperature after welding has a certain influence on the properties of welded joints of low alloy heat-resistant steel. The heat treatment tempering specification is the main factor affecting welding. Experience shows that each low alloy heat-resistant steel has the best tempering parameter range. Selecting the heat treatment temperature after welding can not only reduce the hardness of welding and heat affected zone, but also comprehensively consider other factors, so it can not get the best performance of welded joint and achieve the real purpose of post welding heat treatment. The high content of diffused hydrogen in welding is one of the causes of cold cracks. Therefore, when the structural stress of 13CrMo44 piping is small or the pipe wall is thin, preheating before welding and post welding heat treatment can avoid the occurrence of cracks without subsequent heat treatment. In order to fully release hydrogen and reduce the content of diffused hydrogen in welding, it is correct to adopt the insulation process of 250-350 and 30-60min.
3. The steel pipe heat treatment equipment can improve the corrosion resistance of C90 oil pipe, prevent its tempering brittleness, reduce quenched non martensite and its phase transformation, and eliminate the residual stress formed in the process of pipe rolling deformation and heating by quenching and high temperature tempering.
Hebei FOREVER electromechanical Co., Ltd. is a manufacturer focusing on the production of induction heating equipment and heat treatment equipment. It specializes in customizing induction heating equipment and heat treatment equipment. Welcome to consult.
Overseas manager: Tom Wang
Phone: 0086-13303078975(whatsapp, wechat,line)
Post time: 04-14-2022