WRC 575-2019 PDF

Full title and description

WRC Bulletin 575 (WRC 575:2019) — "Revisiting the Bree Diagram: Derivation with Temperature-Dependent Properties". This bulletin re-examines the original Bree diagram used to assess ratcheting and related cyclic behaviors in thin‑walled cylindrical pressure vessels, updating derivations and extending the diagram to account for temperature‑dependent material properties and differing yield stresses during startup/shutdown sequences.

Abstract

The Bree diagram is a long‑established tool for categorizing cyclic load responses (elastic/plastic cycling, shakedown, and ratcheting) of thin‑walled cylindrical vessels. WRC 575 revisits the original derivation, presents corrected and expanded equations, introduces temperature‑dependent property effects, and provides appendices with step‑by‑step derivations and worked expressions for practitioners and code writers. The bulletin is intended to improve the accuracy of ratcheting assessments used in modern codes and standards.

General information

• Status: Current / Active.
• Publication date: 2019 (listed as 01 January 2019 in publication records).
• Publisher: The Welding Research Council (WRC), New York, NY.
• ICS / categories: Welding technology; pressure vessels and piping; structural fatigue and ratcheting (engineering/pressure‑equipment assessment).
• Edition / version: WRC Bulletin 575 — 2019 edition (WRC 575:2019).
• Number of pages: 214 pages (bulletin length).

Scope

Defines revised derivations for the Bree diagram with explicit inclusion of temperature‑dependent material properties and differential yield behavior during thermal transients. The bulletin derives boundaries between elastic/plastic cycling, shakedown, and ratcheting regions, supplies compact equations for practical use, and includes appendices showing detailed algebraic steps so results can be implemented in design checks, fitness‑for‑service assessments, and code guidance. Applicable primarily to thin‑walled cylindrical shells under combined pressure and thermal/mechanical cyclic loading.

Key topics and requirements

• Re‑derivation of the Bree diagram incorporating temperature‑dependent elastic/plastic properties.
• Definitions and equation sets for regions of elastic cycling, plastic cycling, shakedown, and ratcheting.
• Modifications to account for different startup/shutdown yield stresses and transient conditions.
• Appendices with step‑by‑step derivations and worked examples suitable for implementation in analysis routines.
• Guidance for use in pressure‑vessel design checks and for informing code or standard updates related to ratcheting evaluations.

Typical use and users

Used by mechanical and pressure‑vessel engineers, fatigue and fracture specialists, materials engineers, code and standards committees (ASME/API/WRC), and researchers developing analysis tools for cyclic thermal‑mechanical loading. Typical applications include design and assessment of cylindrical shells, heaters, drums, reactors, and piping components that experience thermal transients and cyclic pressure loads.

Related standards

Other WRC bulletins and documents on related topics (fatigue methods, temperature‑dependent material properties, fitness‑for‑service) are commonly used alongside WRC 575 — examples include WRC Bulletins covering temperature‑dependent property compendia, fatigue standardization for API/ASME, and guidance on minimum pressurization temperature and related high‑temperature behavior. WRC 575 is one item in the WRC bulletin series of technical reports that support ASME/API practices.

Keywords

Bree diagram; ratcheting; shakedown; thin‑walled cylindrical vessels; temperature‑dependent properties; thermal transients; pressure vessels; WRC Bulletin 575; Welding Research Council.

FAQ

Q: What is this standard?

A: WRC Bulletin 575 (WRC 575:2019) is a technical bulletin from the Welding Research Council titled "Revisiting the Bree Diagram: Derivation with Temperature‑Dependent Properties" that re‑derives and extends the classical Bree diagram for use in modern assessments of ratcheting and shakedown.

Q: What does it cover?

A: It covers the mathematical derivation of Bree diagram boundaries, modifications to include temperature‑dependent material behavior, considerations for differing yield stresses at startup/shutdown, and provides appendices with detailed derivations and practical equations for engineering use.

Q: Who typically uses it?

A: Pressure‑vessel designers, mechanical and materials engineers, fatigue analysts, and standards committees (ASME/API/WRC) use this bulletin to support ratcheting and shakedown evaluations for cylindrical shells and related components.

Q: Is it current or superseded?

A: The bulletin is listed as current/active in distributor and standards listings (publication 2019); users should check WRC or recognized standards repositories for any later revisions or subsequent WRC bulletins that may update the guidance.

Q: Is it part of a series?

A: Yes — it is part of the WRC bulletin series of technical reports (WRC Bulletins) that address welding, pressure‑equipment behavior, fatigue, hydrogen attack, and related topics; WRC publishes many numbered bulletins that are commonly referenced together in engineering practice.

Q: What are the key keywords?

A: Bree diagram, ratcheting, shakedown, temperature‑dependent properties, thin‑walled cylinders, pressure vessels, WRC Bulletin 575.