The invention relates to a symmetrical-hot-rolled
composite plate blank and a seal
welding method thereof. An
enclosure frame comprises two parts, the first part forms the inner side of the enclosureframe, and the cross section of the first part is an
isosceles trapezoid; the second part forms the outer side of the
enclosure frame, the cross section of the second part is trapezoidal, and the length of the lower bottom edge of the second part is smaller than the length of the lower bottom edge of the first part; a groove is formed in the side, close to the
enclosure frame, of the end of an upper base material; a special groove structure is formed through the innovative enclosure frame structure design, and the seal
welding process is innovatively divided into two
welding process flows; automatic welding equipment such as an
arc welding robot or a special
machine is adopted, and
laser weld joint tracking and self-adaptive welding equipment is configured; a horizontal position welding mode is adopted, a high-penetration
welding process is adopted for a root welding bead, and a high-deposition-rate
welding process is adopted for a filling welding bead; and compared with the prior art,high-quality, high-efficiency and low-cost seal welding is realized through unique methods such as enclosure frame structure design, groove structure design, two-step
welding process flow, welding
process optimization and automatic welding equipment.