STEEL PIPE FOR HIGH-PRESSURE FUEL LINE AND PRODUCTION METHOD THEREFOR Russian patent published in 2019 - IPC C22C38/00 C21D8/10 F02M55/02 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, in particular to a steel pipe used for the production of high pressure fuel lines. Pipe has a tensile strength of 500–900 MPa, the ratio of yield point to tensile strength of 0.50–0.85, residual stress in the circumferential direction on the inner surface of the pipe after the treatment of the pipe for splitting in half in the direction of the pipe axis is -20 MPa or less, as well as critical internal pressure (IP) satisfying a condition [IP ≥ 0.41 × TS × α], (α = [(D / d)²-1] / [0,776 × (D / d)²], wherein TS is tensile strength (MPa) of the steel pipe, D is an outer diameter of the steel pipe (mm) and d is an inner diameter of the steel pipe (mm), α – a change correction factor in the ratio of internal pressure and voltage, arising on the inner surface of the pipe in accordance with the ratio of the outer diameter and the inner diameter of the pipe.

EFFECT: pipes to be produced have high strength and reliability.

12 cl, 6 dwg, 1 ex, 6 tbl