ASME SA-376-SA-376M:2021 pdf free download – SPECIFICATION FOR SEAMLESS AUSTENITIC STEEL PIPE FOR HIGH-TEMPERATURE CENTRAL-STATION SERVICE
11.1 Each pipe shall be subjected to the Nondestructive Electric Test or the Hydrostatic Test. Unless specified by the purchaser, either test may be used at the option of the producer.
11.2 Hydrostatic Test — Each length of finished pipe shall be subjected to the hydrostatic test in accordance with SpecificationA 999/A 999M, unless specifically exempted under the provisions of 11.3 and 11.4.
11.3 For pipe sizes NPS 24 and over, the purchaser, with the agreement of the manufacturer, may complete the hydrostatic test requirement with the system pressure test, which may be lower or higher than the specification test pressure, butin no case shall the test pressure be lower than the system design pressure. Each length of pipe furnished withoutthe completed manufacturer’s hydrostatic testshall include with the mandatory marking the letters “NH.”
11.4 Nondestructive Examination — Each pipe shall be examined with a nondestructive test in accordance with Practice E 213 or Practice E 426. Unless specifically called out by the purchaser, the selection of the nondestructive electric test will be at the option of the manufacturer. The range of pipe sizes that may be examined by each method shall be subjectto the limitations in the scope ofthe respec- tive practices.
11.4.1.1 The reference standards defined in 11.10.1 through 11.10.4 are convenient standards for cali- bration of nondestructive testing equipment. The dimen- sions of these standards should not be construed as the minimum size imperfection detectable by such equipment.
11.4.1.2 The ultrasonic testing (UT) can be per- formed to detect both longitudinally and circumferentially oriented defects. It should be recognized that different techniques should be employed to detect differently ori- entedimperfections. The examination may notdetectshort, deep, defects.
11.4.1.4 A purchaser interested in ascertaining the nature (type, size, location, and orientation) of discontinu- ities that can be detected in the specific application ofthese examinations should discuss this with the manufacturer of the tubular product.
11.5 Time ofExamination — Nondestructive testing for specification acceptance shall be performed after all mechanical processing, heat treatments, and straightening operations. This requirement does not preclude additional testing at earlier stages in the processing.
11.6 Surface Condition:
11.6.1 All surfaces shall be free ofscale, dirt, grease, paint, or other foreign material that could interfere with interpretation oftestresults. The methods used forcleaning and preparing the surfaces for examination shall not be detrimental to the base metal or the surface finish.
11.10.3.1 Drilled Hole — The reference standard shallcontainthree ormoreholes, equally spacedcircumfer- entially around the pipe and longitudinally separated by a sufficient distance to allow distinct identification of the signal from each hole. The holes shall be drilled radially and completely through the pipe wall, with care being taken to avoid distortion of the pipe while drilling. One hole shall be drilled in the weld, if visible. Alternately, the producer of welded pipe may choose to drill one hole in the weld and run the calibration standard through the test coils three times with the weld turned at 120° on each pass. The hole diameter shall vary with NPS as follows