ISO 3977-2-2023 PDF

Full title and description

ISO 3977-2:2023 — Gas turbines — Procurement — Part 2: Standard reference conditions and ratings. This part of ISO 3977 defines the ISO standard reference conditions and the corresponding rating definitions used when specifying and procuring gas turbines, enabling consistent reporting of power, efficiency and fuel consumption between manufacturers and purchasers.

Abstract

This document specifies the standard reference conditions and ISO standard ratings for gas turbines, including the reference atmospheric conditions used to define ISO power and related performance ratings for procurement and contractual purposes. The standard provides the basis for reporting and comparing guaranteed and catalogue ratings.

General information

• Status: Published.
• Publication date: 24 March 2023 (Edition 2, published March 2023).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 27.040 (Gas and steam turbines; steam engines).
• Edition / version: Edition 2 (2023).
• Number of pages: 3 (concise technical specification).

Scope

ISO 3977-2:2023 establishes the standard reference atmospheric conditions and the definitions of ISO ratings for gas turbines that are used in procurement documentation. It sets the basis for expressing power, heat rate, specific fuel consumption and related performance figures at a defined reference point so that equipment offered by different suppliers can be compared on a common basis. The part is intended for use by turbine manufacturers (packagers), purchasers and parties preparing contractual and technical acceptance documents.

Key topics and requirements

• Definition of ISO standard reference conditions (reference ambient temperature, pressure and humidity) used to report ISO power and performance ratings.
• Standardized rating terms (ISO power, ISO efficiency, ISO heat rate, ISO specific fuel consumption) and how they relate to procurement guarantees.
• Requirements for specifying which rating (ISO or site) is being quoted and for reporting the reference conditions used.
• Guidance for applying corrections between ISO reference ratings and actual site operating conditions (site temperature, elevation/pressure, humidity). (Guidance-level; specific correction procedures are generally supplier-specific or covered in other parts of the series.)
• Use in procurement and contractual documentation to avoid ambiguity in guaranteed performance and to provide a consistent basis for comparisons.

Typical use and users

Primary users are gas-turbine manufacturers (packagers), purchasing engineers, consulting engineers, plant owners/operators, and test/acceptance teams. Typical uses include preparing technical specifications, writing contractual guarantees, producing catalogue data, and converting supplier ratings to expected site performance for selection and commercial evaluation.

Related standards

ISO 3977-2 is part of the ISO 3977 series on gas turbine procurement (other parts cover general definitions, design requirements, fuels and environment, inspection and testing, reliability and related topics). Related documents often referenced in procurement activities include the other parts of ISO 3977 (e.g., Part 1 — general introduction and definitions; Part 3 — design requirements) and industry standards that address test procedures or fuel specifications.

Keywords

Gas turbine, procurement, ISO rating, ISO conditions, reference conditions, ISO power, ISO heat rate, performance rating, site correction, ISO 3977.

FAQ

Q: What is this standard?

A: ISO 3977-2:2023 is the part of the ISO 3977 series that defines the standard reference atmospheric conditions and the ISO performance/rating terminology used when specifying and procuring gas turbines. It provides the common reference used for reporting ISO power and related performance figures.

Q: What does it cover?

A: It covers the definition of reference ambient conditions and the definitions of ISO ratings (power, efficiency, heat rate, specific fuel consumption) used for catalog and guaranteed values in procurement and contractual documents; and it establishes the expectation that reported ratings state the reference conditions used.

Q: Who typically uses it?

A: Manufacturers (packagers), procurement and design engineers, plant owners/operators, testing and acceptance teams, and consultants involved in specifying, buying or comparing gas turbines.

Q: Is it current or superseded?

A: Current. ISO 3977-2:2023 (Edition 2) was published in March 2023 and supersedes the earlier ISO 3977-2:1997. Users should reference the 2023 edition for current procurement wording and definitions.

Q: Is it part of a series?

A: Yes — ISO 3977 is a multi-part series addressing procurement of gas turbines (general definitions, reference conditions and ratings, design requirements, fuels and environment, testing and commissioning, reliability, etc.). ISO 3977-2 is the dedicated part for reference conditions and ratings within that series.

Q: What are the key keywords?

A: ISO rating, ISO conditions, standard reference conditions, ISO power, heat rate, specific fuel consumption, gas turbine procurement, ISO 3977.