0

Full Content is available to subscribers

Subscribe/Learn More  >

Proposed Methodology Changes to Determine Minimum Design Metal Temperature of ASME/API Impact Tested Materials Based on Fracture Mechanics

[+] Author Affiliations
Seetha Ramudu Kummari, Brian Macejko, Phillip E. Prueter

The Equity Engineering Group, Inc., Shaker Heights, OH

Paper No. PVP2018-84795, pp. V03BT03A029; 10 pages
doi:10.1115/PVP2018-84795
From:
  • ASME 2018 Pressure Vessels and Piping Conference
  • Volume 3B: Design and Analysis
  • Prague, Czech Republic, July 15–20, 2018
  • Conference Sponsors: Pressure Vessels and Piping Division
  • ISBN: 978-0-7918-5163-0
  • Copyright © 2018 by ASME

abstract

For equipment designed to ASME or API standards, it is common practice to perform impact testing of base material and/or weldments to establish the Minimum Design Metal Temperature (MDMT). The impact test is typically a Charpy V-Notch (CVN) test and the test temperature is set equal to the MDMT. The required Charpy energy at MDMT can vary anywhere from 10 ft-lbs to 40 ft-lbs depending on material specification, thickness, and the ASME/API standard. The detailed historical background behind the Charpy energy requirements of different ASME/API standards is not well documented. Additionally, no credit is given for post weld heat treatment (PWHT) of impact tested materials. The CVN tests are used because they are quick and economical for quality control, but the tests only provide a relative indication of material toughness. Consequently, the current impact test requirements lead to inconsistent results in brittle fracture assessments, conducted through explicit fracture mechanics.

In this paper, two examples are presented to highlight the inconsistencies of the current impact test requirements. A methodology of estimating MDMT for impact tested materials based on fracture mechanics, consistent with Welding Research Council (WRC) Bulletin 562 [1] is also presented. Furthermore, this methodology explicitly accounts for the effects of PWHT (and the influence of weld residual stress on crack driving force) for impact tested materials. A methodology of adjusting MDMT for in-service impact tested materials is also presented. In the interest of moving towards harmonizing the impact test requirements, an alternative procedure for establishing impact test requirements is presented for ASME/API consideration.

Copyright © 2018 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In