ISO 9327-1:1999

Overview

ISO 9327-1:1999 - "Steel forgings and rolled or forged bars for pressure purposes - Technical delivery conditions - Part 1: General requirements" defines the general technical delivery conditions for forgings and rolled/forged bars used in pressure applications. It sets out the framework common to the material-specific parts (ISO 9327‑2 to ISO 9327‑5) and covers ordering, manufacturing, testing, inspection, marking and delivery documentation for steel forgings and bars intended for pressure vessels and related equipment.

Key topics and requirements

• Scope and product types: Applies to open and closed die forgings (including ring-rolled) and rolled or forged bars for pressure purposes. Covers materials addressed in Parts 2–5 (non‑alloy/alloy ferritic & martensitic, nickel steels, weldable fine‑grain steels, and austenitic/duplex stainless steels).
• Ordering information: Purchaser must specify quantity, product form, applicable ISO part, steel type, heat‑treatment condition, ruling section for cross‑sectional sampling, surface finish, inspection document type and any supplementary options from Annex C.
• Manufacturing processes: Requirements for steelmaking, deoxidation (fully killed steels except stainless), hot working, heat treatment and surface finish; manufacturer retains discretion for many process choices unless otherwise agreed.
• Chemical composition: Cast analysis limits and allowable deviations for product analysis are specified by the relevant material part (with options for fine‑grain steels to declare alloy type).
• Mechanical properties: Mandatory room‑temperature tensile and specified impact properties; elevated temperature proof strength and creep/rupture estimates are referenced in material parts.
• Weldability and soundness: General weldability guidance and requirements for internal soundness (free from detrimental internal imperfections). Welding procedures and non‑destructive testing may be agreed as supplementary requirements.
• Inspection, testing and documentation: Conformance testing, inspection certificates (e.g., ISO 10474 types 3.1.A / 3.1.C / 3.1.B) and inspection body involvement are defined.
• Marking and surface quality: Requirements for marking, cast separation and agreed surface discontinuity limits. Annex A defines ruling sections/equivalent diameters; Annex B lists usual stainless steel surface conditions; Annex C lists supplementary options.

Applications and intended users

Who uses ISO 9327-1:

• Manufacturers and foundries producing steel forgings and rolled/forged bars for pressure equipment
• Purchasers, procurement and quality managers specifying delivery and inspection conditions
• Pressure vessel, boiler and piping fabricators and designers referencing material delivery conditions
• Inspection bodies and testing laboratories verifying conformance and issuing certificates

Typical applications:

• Pressure vessels, heat exchangers, boilers, high‑pressure piping, valves and flanges where traceable, specified steel forgings or bars are required.

Related standards

• ISO 9327 parts 2–5 (material-specific delivery conditions)
• ISO 404 (general technical delivery requirements)
• ISO 10474 (inspection documents)
• ISO 6929 (definitions/classification of forgings)
• ISO/TR 15461 (testing frequency and sampling) and other ISO standards referenced in the text

Keywords: ISO 9327-1, steel forgings, rolled bars, pressure purposes, technical delivery conditions, heat treatment, chemical composition, mechanical properties, inspection certificate.