PROCEDURE DETERMINING RESIDUAL SERVICE LIFE OF PIPE-LINE Russian patent published in 2002 - IPC

FIELD: diagnostics of pipe-lines to evaluate their residual service life. SUBSTANCE: procedure determining residual service life of pipe-line consists in detection of zone with potentially low service life, in finding in this zone point with such plastic properties to which maximum coercive force corresponds, in conducting local deformation of material in found point, in determination of relative elongation of it by its results. Residual service life of pipe-line is evaluated by ratio of this index to reference value of given index of plasticity. Zone with maximum effective stresses is chosen as zone with potentially lowered service life. Approximate boundary of point to which plastic properties maximum coercive force corresponds is found by value of elastic mechanical stresses detected by methods of nondestructive inspection. Absolute values of axial σ₁ and tangential σ₂ elastic stresses acting in pipe-line are found by calculation. EFFECT: enhanced authenticity of determination of residual service life of pipe-line. 2 cl, 3 dwg