ASME B16.11 - markings verification

Identification markings

An actual marking on product shall reflect that product has manufactured accordance to the specification and its original. It is necessary to cross check with the material test report.

Each fitting shall be permanently marked with the required identification by raised lettering and/or stamping. Cylindrical fittings shall be marked on the O.D. or end of the fitting in a location such that the marking will not be obliterated as a result of welding installation (ASME B16.11).

ASME B16.11 covers normal size from 1/8" to 4". Fittings shall be made of materials consisting of forgings, bar, seamless pipe, or seamless tubular products. See latest edition on ANSI Store.

Identification markings

Reqquired Description Verified (refer photo)
Name: manufacturer’s name or trade-marks I.M.L
Material identification material designation ASTM A105N or ASTM A182
Class Designation rating 3000 lbs or 6000 lbs
Product Conformance forming specification B16.11 or B16
Size SI or US Customary Units NPS 1" or DN25
Heat number identification number T3Z

astm_a182_f316l astm_a105n astm_a105n


  • Visual inspection: overall check surface condition and marking information.
  • Dimensional inspection: type of flange and class, material, size, etc. Acceptance criteria refer to ASME B16.11 para 6 and para. 7.


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As per UG 93 of ASME sec 8 Except for plates the rest of materials need not require an MTC ,Product marking is enough.

Could you quote the para. in ASME Section VIII ?

In my opinion, MTC shall provide for inspecion and view the incoming material.
If material subject to fabricate pressure vessel, the pressure containing items shall be identified and able to trace.


how to inspect the weldoutlet joint.

Determine weld size and thickness as given in ASME B31.3 2018 Para 328.5.4 Welded Branch Connections and Table 341.3.2 Acceptance Criteria for Welds .