FOR STEEL PIPES
General Requirements – ASTM A530
1. Each length of pipe shall be legibly marked with themanufacturer’s name or brand, the specification number (year of issue not required) and grade. Marking shall begin approximately 12 in. [300 mm] from the end of each length of pipe. For pipe less than NPS 2 and pipe under 3 ft [1 m] in length, the required information may be marked on a tag securely attached to the bundle or box in which the pipes are shipped.
2. For austenitic steel pipe, the marking paint or ink shall not contain any harmful metal, or metal salts, such as zinc, lead, or copper, which cause corrosive attack on heating.
3. Pipes which have been weld repaired shall be marked WR.
4. When it is specified that certain requirements of a specification adopted by the ASME Boiler and Pressure Vessel Committee are to be completed by the purchaser upon receipt of the material, the manufacturer shall indicate that all requirements of the specification have not been completed by a letter such as X, Y, or Z, immediately following the specification number.
5. Bar Coding—In addition to the requirements in 1, 2, 3, 4 and 5, bar coding is acceptable as a supplemental identification method. The purchaser may specify in the order a specific bar coding system to be used.

ASTM A53
1. Manufacturer’s name or mark,
2. Specification number (year-date not required),
3. Size (NPS and weight class, schedule number, or specified wall thickness; or specified outside diameter and
specified wall thickness),
4. Grade (A or B),
5. Type of pipe (F, E, or S),
6. Test pressure, seamless pipe only,
7. Nondestructive electric test, seamless pipe only.(in accordance with table below)

FOR STEEL VALVES  MSS SP-25FOR STEEL FLANGES AND PIPE FITTINGS  MSS SP-25
1. Manufacturer’s name or trademark,
2. Material designation,
3. Rating designation,
4. Size,
5. Ring-joint flange ring number, when applicable,
6. Melt identity(when specified)

Body Markings.
The following markings shall be cast, stamped, forged, or engraved on the body of the valve, or on a permanently attached marked plate(note). Markings that are obliterated during manufacture may be replaced by weld deposition, stamping, engraving, or permanently attached marked plates, at the option of the manufacturer.
1. Manufacturer’s name or trademark,
2. Material designation,
3. Rating designation,
4. Mellt identification,
5. Nominal pipe size,
6. Thread identification, when required,
7. Ring joint identification number, when applicable,
8. Additional markings are permitted.
Note: The permanently attached marked plate on the body should not be confused with the identification plate  mentioned below. The permanently attached plate is for the purpose of showing body markings.

Identification Plate Markings.
1. Manufacturer ‘s name or trademark,
2. Body material designation(note),
3. Rating designation,
4. Service limitation.- the valve rating at 100°F including any special limitations such as maximum pressure differential, and/or temperature limits due to valve construction features such as packings and seats.
5. Valve trim identification.
6. Additional marketings are permitted.
Note: these required makings, if shown on the body, need not be duplicated on the identification plate.

FACTORY – MADE WROUGHT BUTTWEIDING FITTINGSASMB B16.9 Section 4
1. Standard Marking
Each fitting shall be permanently marked to show the following:
(a) manufacturer’s name or trademark,
(b) material identification, either the ASTM or ASME grade designation,
(c) schedule number or nominal wall thickness in mm,
(d) size — the nominal pipe size (NPS) identification number related to the end connections shall be used,
(e) compliance
A manufacturer may supplement these mandatory markings with others, including a DN size designation, but confusion with the required marking shall be avoided.
2. Exceptions
Where the size of the fitting does not permit complete marking, the identification marks may be omitted in reverse of the order presented above.
3. Depth of Stamping
Where steel stamps are used, care shall be taken so that the marking is not deep enough or sharp enough to cause cracks or to reduce the wall thickness of the
fitting below the minimum allowed.

FORGED FITTINGS, SOCKET-WELDING AND THREADED ASME B16.11 Section 4
1. General
Each fitting shall be permanently marked with the required identification by raised lettering and/or stamping, electro-etching, or vibro-tool marking on the collar portion, raised pad, or raised boss portion of the forging. 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. The marking of bushings and plug is not required by this Standard.
2. Specific Marking.
The marking shall include (but is not limited to) the following:
(a) Manufacturer’s Name or Trademark,
(b) Material Identification. Material shall be identified in accordance with the marking requirements of either the appropriate ASTM Fittings Specification A 234,A 403, A 420, A 815, or B 366, or the appropriate ASTM Forging Specifications A 105, A 182, A 350, B 160, B 164, B 462, B 564, or other applicable forging Specification of Table 1, ASME B16.34,
(c) Product Conformance. Fittings covered under para. 1.1.1 of ASME B16.11 shall be marked with either the ASTM Fittings Specification material identification or the symbol “B16” to denote conformance to this Standard. Fittings covered underof ASME B16.11 para. 1.1.2 shall be marked B16SPLD.
(d) Class Designation. 2000, 3000, 6000, or 9000, as applicable. Alternatively, the designation 2M, 3M, 6M, or 9M, as applicable, may be used where M stands
for 1000.
(e) Size. The nominal pipe size related to the end connections.
3 Omission of Markings.
Where size and shape of fittings do not permit all of the above markings, they may be omitted in the reverse order given above.

PIPE FLANGES AND FLANGED FITTINGS ASME B16.5 Section 4
1. General
Except as modified herein, flanges and flanged fittings shall be marked as required in MSS SP-25, except as noted in para. 2.
2. Identification Markings
2.1 Name. The manufacturer’s name or trademark shall be applied.
2.2 Material. Material shall be identified in the following way:
(a) Cast flanges and flanged fittings shall be marked with the ASTM specification, grade identification symbol (letters and numbers), and the melt number or melt identification.
(b) Plate flanges, forged flanges, and flanged fittings shall be marked with the ASTM specification number and grade identification symbol.
(c) Amanufacturer may supplement these mandatory material indications with his trade designation for the material grade, but confusion of symbols shall be avoided.
(d) For flanges and flanged fittings manufactured from material that meets the requirements of more than one specification or grade of a specification listed in Table 1A, see para. 8.
3. Rating Designation. The flange or flanged fitting shall be marked with the number that corresponds to its pressure rating class designation (i.e., 150, 300, 400, 600, 900, 1500, or 2500).
4. Conformance. The designation B16 or B16.5 shall be applied to the flange or flanged fitting, preferably located adjacent to the class designation, to indicate conformance to this Standard. The use of the prefix ASME is optional.
5. Temperature. Temperature markings are not required on flanges or flanged fittings; however, ifmarked, the temperature shall be shown with its corresponding
tabulated pressure rating for the material.
6. Size. The NPS designation shall be marked on flanges and flanged fittings. Reducing flanges and reducing flanged fittings shall be marked with the applicable NPS designations as required by paras. 3.2 and 3.3 of ASME B16.5
7. Ring Joint Flanges. The edge (periphery) of each ring joint flange shall be marked with the letter R and the corresponding ring groove number.
8. Multiple Material Marking. Material for components that meet the requirements for more than one specification or grade of a specification listed in Table 1A of ASME B16.5 may, at the manufacturer’s option, be marked with more than one of the applicable specification or grade symbols. These identification markings shall be placed so as to avoid confusion in identification. The multiple marking shall be in accordance with the guidelines set out in ASME Boiler and Pressure Vessel Code, Section II, Part D, Appendix 7.