Manufacturing method for hollow stabilizer

A manufacturing method for making a hollow stabilizer, comprising:

• a primary pipe manufacturing process for subjecting a seam-welded pipe to continuous hot reduction working, thereby obtaining a primary pipe, and winding the primary pipe in a coil;
• a cold drawing process for subjecting the primary pipe to cold drawing so that a rate of reduction in area is not lower than 30%, thereby obtaining a thick-walled pipe having a wall thickness ratio of 0.20 to 0.27 and a tensile strength of 800 N/mm2 to 1,000 N/mm2, said wall thickness ratio of 0.20 to 0.27 being higher than a wall thickness ratio of the seam-welded pipe;
• a bending process for bending the thick-walled pipe, obtained in the cold drawing process, into a desired stabilizer shape in a cold state;
• an annealing process for subjecting the thick-walled pipe to stress relieving annealing at a temperature of 300° C. to 450° C., after the bending process;
• and
• a shot peening process for shot-peening the thick-walled pipe while the pipe is kept at a temperature of 300° C. to 400° C., after the annealing process.