Electroseamed steel pipe for hollow stabilizer, hollow stabilizer, and production methods therefor

Abstract

This electro-sealed steel tube used for a hollow stabilizer comprises a base material portion and a welded portion. The base material portion includes a prescribed chemical component. The thickness of the base material portion is 2.0 to 6.0 mm. The electro-sealed steel tube has an outside diameter of 10 to 40 mm. In a cross-section in direction C of the electro-sealed steel tube, a bead-shaped recess is present in an area that includes the welded portion and is located on the inner surface of the electro-sealed steel tube. When a virtual line is drawn at the shortest distance from one opening edge of the recess to the other, the maximum depth from the virtual line to the bottom of the recess is at most 300 μm. The largest inclusion in the base material portion has a diameter of at most 300 μm.The surface roughness on the inner surface of the base material portion of the electro-sealed steel tube is a maximum of 300 μm at the maximum depth of the Rv valley. The electro-sealed steel tube, including the welded portion, has a maximum hardness of 300 Hv. (Automatic translation using Google Translate, not legally binding).