Haw. Code R. § 6-77-96 - Repair of steel pipe

(a) Each imperfection or damage that impairs the 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.

Notes

Haw. Code R. § 6-77-96

[Eff ] (Auth: HRS § 269-6) (Imp: 49 C.F.R. §192.309, OCT 1, 1990)