The on-line non-oxidative complete solution treatment method of a stainiess arc weldedpipe

摘要

The present invention relates to a complete solid-state heat treatment method for an online non-oxidizing atmosphere of a stainless arc welded steel pipe, and more particularly, to the inside of a weld portion generated by welding heat when the austenitic and duplex stainless steel pipes are welded by arc welding. Automatically heat treats and corrects tissue defects in an oxidizing atmosphere, thereby improving product quality by securing good heat treatment structure, corrosion resistance and beautiful welded surface, and shortening the overall heat treatment process to reduce manufacturing cost and prevent environmental pollution. It is about what can be done.;According to the present invention, a method for completely solidifying an on-line non-oxidizing atmosphere of a stainless steel arc welded steel pipe according to the present invention is to bend a strip-shaped large steel made of stainless steel into a pipe shape, and join both sides of the large steel by arc welding to produce a stainless steel pipe (2) Weld tube processing (11) for forming a mold, welding bead processing step (12) for processing weld beads in accordance with the outer diameter of the stainless steel pipe (2), and correcting the internal texture defects of the weld portion caused by the welding heat in the arc welding process In the heat treatment step 20, the heat treatment step 20 is performed after the welding bead processing step 12, and then the stainless steel pipe 2 is automatically inserted into the quartz tube 3 filled with argon gas. After supplying and heating the stainless steel pipe (2) for 5 to 18 seconds at a temperature of 1000 ~ 1050 ℃, after the welded steel pipe heating step (21), the welded steel pipe heating step (21), The inlet steel pipe (2) is automatically supplied to the inside of the quartz tube (4) filled with hydrogen gas so that the weld is locally heated for 15 to 60 seconds at a temperature of 1250 to 1350 ° C, and the remaining portion is After the welding part local heating and cooling step 22 and the welding part local heating and cooling step 22 described above, the stainless steel pipe 2 is automatically inserted into the cooling tube 5 equipped with cooling water at room temperature. It is characterized by passing through a quenching step 23 to indirectly cool by supplying the carbon tube contact method.