What is ISO 4991 - Steel castings about?
ISO 4991 is an international standard on steel castings for pressure purposes that discusses the best procedures and specifications on manufacturing high-quality steel castings. ISO 4991 covers steel castings for pressure-containing parts. ISO 4991 includes materials that are used for the manufacture of components subject to pressure vessel codes and components not subject to codes.
ISO 4991 relates to castings manufactured from unalloyed and alloyed steel grades (characterized by their chemical composition, Table 1, and mechanical properties, Tables 2, 3, 4, and 5).
NOTE: Annex D gives information on ISO grade designation and available UNS numbers which are similar to the ISO grade designation.
Who is ISO 4991 - Steel castings for?
ISO 4991 on steel castings for pressure purposes is relevant to:
- Manufacturer of steel castings
- Manufacturer of pressure appliance or pressure-containing parts
Why should you use ISO 4991 - Steel castings?
Cast steel is a ferrous alloy with a maximum carbon content of approximately 0.75%. Steel castings are solid metal objects produced by filling the void within a mold with liquid steel. They are available in many of the same carbon and alloy steels that can be produced as wrought metals.
ISO 4991 provides guidance on heat treatment, welding, chemical composition, mechanical properties, inspection, and testing.
ISO 4991 navigates you through the manufacturing process, welding operations, casting, corrosion behavior, materials, inspection methods.
ISO 4991 exemplifies the required chemical composition and, mechanical properties that help you achieve precision in terms of product functionality and specification.
As a user of ISO 4991, you can be ensured of all the requirements for steel castings. With obedience and compliance to ISO 4991, you can efficiently manufacture high-quality steel castings for pressure-containing parts. With ISO 4991 you can be ensured that the products consistently meet and exceed quality assurance targets. ISO 4991 provides you with comprehensive information useful throughout the process of production.
What’s changed since the last update?
BS ISO 4991:2015 cancels and replaces the second edition (ISO 4991:2005), which has been technically revised. In particular, the following changes have been made:
- New and replacement International Standards have been added to the normative references (see Clause 2)
- A new numbering system has been included in all tables
- In Table 1, grade designations and composition limits have been changed where appropriate
- A new Annex D containing Table D.1, showing UNS grades similar to ISO cast grades, has been added
