ANSI MSS SP-25 pdf free download
ANSI MSS SP-25 pdf free download.Standard Marking System for Valves, Fittings, Flanges, and Unions.
3. MANUFACTURER’S NAME OR TRADEMARK
All valves, fittings, flanges, and unions shall be marked with the manufacturer’s name, trademark, logo, or symbol. See Section 11 for permissible omissions.
4. RATING DESIGNATION
4.1 The expression “Rating Designation” includes the intent of the expressions “Pressure Designation”, “Class Designation”, ‘Pressure Class”, and similar tenns used to define the pressure and temperature limitations of the product. The rating designation shall be shown by one of the systems in the sections that follow:
4.1.1 The rating designation for products that fully conform to recognized standards may be designated by the Class numbers alone (e.g., a steam pressure rating or a pressure class designation). Pressure Rating Values maybe abbreviated by using “M” to designate units of one thousand (e.g., 3M used in place of 3000 ).
4.1.2 The rating designation for products that may conform to recognized standards, however, are not suitable for the full range of pressures or temperatures of these standards (where allowed), shall be marked as prescribed in Sections 4.1.3 and 4.1.4, as appropriate, and shall also show the numbers and letters representing the service limitation at the limiting condition.
4.1.3 The rating designation for products that do not conform to recognized product standards may be shown by numbers and letters representing the pressure ratings at the corresponding temperatures in the following format:
“2000 AT 100F 725 AT 925F”
The rating designation may also be shown as the maximum pressure followed by “CWP””’ and the allowed pressure at the maximum temperature, seen in the following format:
“2000 CWP 725 AT 92SF”
Products intended for ambient room temperature may show the allowable pressure followed by letters CWP or equivalent, seen in the following format:
“2000 CWP”
4.1.4 Products with dual or multiple rating designations may be marked with maximum pressure at CWP and the allowable pressure at the maximum temperature, seen in the following format:
“2000 CWP 725 AT 925 F”
4.1 .5 Products with rating designations which are constant throughout a specified temperature range may be marked with maximum pressure at the maximum temperature, seen in the following format:
“2000 CWP 925F MAX”
4.2 When marking in SI (metric) notation, the units of preference will be baror kilopascals (kPa) of gauge pressure, and degrees Celsius for temperature. Numbers designating pressure will be followed by the term “BAR” or bKPA, and temperature designation by the letter “C”. Conversion of direct pressure values is permitted, but conversion of pressure classes to “metric equivalents” should not be attempted.
Format Example: ‘150 BAR at 500C”
4.3 Products made to attach to a specific pipe may be marked with the appropriate pipe schedule number or pipe wall designation.
4.4 Special markings for rating designation may be specified in individual product standards.
5. MATERIAL DESIGNATION
5.1 Products made of conforming materials shall be marked in accordance with ASTM, ASME, or other recognized material specifications, as described in the following Product Marking sections. In a composite structure made of several materials, the material limiting its pressure-temperature rating shall be marked. In addition, products may instead be marked with proprietary material designations, but confusion shall be avoided with standardized material symbols or markings, and other sections of this Standard Practice.
5.2 Products made of one material and lined with another, excluding corrosion resistant coatings, shall carry the regular markings specified by this Standard Practice and additional markings indicating:
(1) that the product is lined, and
(2) the material used for its lining (e.g. RL NR).
5.3 Material markings are not required on ASTM B61, ASTM B62, and ASTM B584 alloys, UNS
C83800 and UNS C84400, cast copper alloy threaded or solder-joint fittings, flanges, unions, valves, or
wrought copper solder-joint products. Note that “UNS” denotes “Unified Numbering System”, an alloy
designation system of a prefix letter and five digits designating a material composition.
5.4 Material marking is not required for gray iron, except as shown in Section 12.2.
Alloyed gray iron may be identified by a manufacturer’s symbol, provided that confusion with standardized and customary symbols or markings is avoided.
5.5 Marking Nameplates and Bodies — Metallic The preferred industry method of identification for steel and iron (ferrous) materials are the appropriate ASTM specification number and/or grade symbol, and for other metallic materials (including non-ferrous) it is the Unified Numbering System (UNS) alloy designation. The material grade or some other abbreviation, such as the illustrative material examples shown in Table Al, may also be used for ferrous and non-ferrous material identification, as applicable. However, products with steel bodies shall be primarily marked with the applicable ASTM specification grade identification symbol.
Non-ferrous body materials may be marked with the symbols shown in Table A I, in addition to other marking that may be required.
Other symbols, including manufacturer’s trade names and material codes, arc permitted, but confusion shall be avoided with standardized and common symbols or markings.ANSI MSS SP-25 pdf download.
