Abstract: Described and analyzed in the paper are the quality defects of the cold-bent opening steel shapes produced from the weld pipe mill with conventionally designed roll groove. Also described here are the experimental activities of designing the said roll groove with local restriction method. The result shows that thanks to the newly designed roll groove all the quality defects of the said steel shapes can be eliminated effectively, and forming passes can be lessened, increasing both the yield and the comprehensive technico-economic benefit.