ISO 4991-2015 pdf free.Steel castings for pressure purposes.
ISO 4991 covers steel castings for pressure containing parts.
It includes materials which are used for the manufacture of components subject to pressure vessel codes and components not subject to codes.
This International Standard relates to castings manufactured from unalloyed and alloyed steel grades (characterized by their chemical composition, Tab1 L and mechanical properties, Tb1es2, j 4 and 5). NOTE Annex D gives information on ISO grade designation and available UNS numbers which are similar to the ISO grade designation.
2 Normative references
The following documents, in whole or in part, arc normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition olthc referenced document (including any amendments) applies.
ISO 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 4885, Ferrous products — Heat treatments — Vocabulary
ISO 4990. Steel castings — General technical delivery requirements
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6892-2, Metallic materials — Tensile testing — Part 2: Method of test at elevated temperature
ISO 11970, Specification and approval of welding procedures for production welding of steel castings
ISO 13520, Determination offerrite content in austenitic stainless steel castings
3 Terms and definitions
For the purposes o this document, the terms and definitions given in ISO 4885 and ISO 4990 apply.
4 Information to be supplied by the purchaser
Materials specified in this International Standard shall conform to the applicable requirements of ISO 4990 including the supplementary requirements listed in Annex A that are indicated in the enquiry and purchase order.
5 Heat treatment
The type of heat treatment shall comply with Table for the specified grades. The temperatures given are for information only.
When a grade may be delivered at different strength levels depending on the type of heat treatment (see Table 2), the purchaser shall state at the time of enquiry and order the type of heat treatment required.
The symbols for the type of heat treatment are as follows:
+N normalized
+QT quenched and tempered
+AT solution annealed
NOTE For definitions, see ISO 4885.
6 Welding
Welding is permitted, unless otherwise agreed. All the welds shall conform to the same criteria for non-destructive testing as the relevant part of the casting. Welding shall be carried out in accordance with Iso 11970.
The welding conditions are given in AnnexE.
7 Requirements
7.1 Chemical composition
An analysis of each heat shall be made by the manufacturer to determine the contents of the
specified elements.
The chemical composition shall comply with the values given in Table 1.
Permissible deviations for the product analysis are indicated in ISO 4990.
7.2 Mechanical properties
The mechanical properties shall comply with the values given in Tables2. 3. 4 and 5.
Mechanical properties shall be measured on test pieces taken from test blocks (according to ISO 4990).
The tensile tests at room temperature shall be carried out according to ISO 6892-1 and, if specified, impact tests according to ISO 148-1.
If required by agreement at the time of enquiry and order, impact energy properties at low temperature shall comply with Table 3.
If required by agreement at the time of enquiry and order, impact energy values at room temperature shall comply with Table 4.
If required by agreement at the time of enquiry and order, verification of the elevated temperature proof stress values shall be carried out at elevated temperatures in accordance with ISO 6892-2. In such a case, the values shall comply with Table 5.
Creep resistance mean values are given for Information, for some grades in Annex C.ISO 4991 pdf download.