HAR 6-77-96
HAR 6-77-96 Repair of steel pipe
serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding, the remaining wall thickness must at least be equal to either:#
(1)The minimum thickness required by the tolerances in the specification to which the pipe was manufactured; or#
(2)The nominal wall thickness required for the design pressure of the pipeline.#
(b)Each of the following dents must be removed from steel pipe to be operated at a pressure that produces a hoop stress of twenty percent, or more, of SMYS:#
(1)A dent that contains a stress concentrator such as a scratch, gouge, groove, or arc burn;#
(2)A dent that affects the longitudinal weld or a circumferential weld; and#
(3)In pipe to be operated at a pressure that produces a hoop stress of forty percent or more of SMYS, a dent that has a depth of: (A) More than one-quarter inch in pipe 12-3/4 inches or less in outer diameter; or (B) More than two percent of the nominal pipe diameter in pipe over 12-3/4 inches in outer diameter. For the purpose of this subsection a "dent" is a depression that produces a gross disturbance in the curvature of the pipe wall without reducing the pipe-wall thickness. The depth of a dent is measured as the gap between the lowest point of the dent and a prolongation of the original contour of the pipe.#
(c)Each arc burn on steel pipe to be operated at a pressure that produces a hoop stress of forty percent, or more, of SMYS must be repaired or removed. If a repair is made by grinding, the arc burn must be completely removed and the remaining wall thickness must be at least equal to either:#
(1)The minimum wall thickness required by the tolerances in the specification to which the pipe was manufactured; or#
(2)The nominal wall thickness required for the design pressure of the pipeline.#
(d)A gouge, groove, arc burn, or dent may not be repaired by insert patching or by pounding out.#
(e)Each gouge, groove, arc burn, or dent that is removed from a length of pipe must be removed by cutting out the damaged portion as a cylinder. [Eff ] (Auth: HRS '269-6) (Imp: 49#