STEEL PIPE DEFORMABILITY ESTIMATION METHOD AND STEEL PIPE MANUFACTURING METHOD Russian patent published in 2020 - IPC B21C37/08 

FIELD: pipelines.

SUBSTANCE: invention relates to production of pipes, more specifically, pipes made by expansion using an expander. Method includes step of obtaining information on external shape by measuring shape of steel pipe to obtain information on external shape, step of obtaining information on energy spectrum from obtained wavy external shape of steel pipe, wherein energy spectrum is obtained by dividing signal power by predetermined frequency ranges and energy spectrum is signal power in each frequency band as a function of frequency, and the steel pipe deformability determining step by integrating the obtained energy spectrum for the predetermined wavelength range and determining the steel pipe deformability based on the obtained integral, wherein if the integral is less than or equal to a predetermined value, the predetermined level of deformability is satisfactory. If the deformability does not satisfy the preset level of deformability, the pipe expansion pitch is reduced at the stage of expansion of the pipe by means of an expander.

EFFECT: invention provides the possibility of controlling the shape of articles under certain tolerances for their manufacture.

2 cl, 11 dwg, 1 tbl