0

Full Content is available to subscribers

Subscribe/Learn More  >

The Case for MACA: The Optimization of Corrosion Allowance

[+] Author Affiliations
Jaan Taagepera

Chevron Energy Technology Co., Richmond, CA

Paper No. PVP2016-63074, pp. V003T03A030; 5 pages
doi:10.1115/PVP2016-63074
From:
  • ASME 2016 Pressure Vessels and Piping Conference
  • Volume 3: Design and Analysis
  • Vancouver, British Columbia, Canada, July 17–21, 2016
  • Conference Sponsors: Pressure Vessels and Piping Division
  • ISBN: 978-0-7918-5039-8
  • Copyright © 2016 by ASME

abstract

Engineers are taught to optimize. In the case of pressure vessel design, one means of optimizing the steel which is used is to increase the rated pressure capacity of the vessel beyond the design needs. This optimized pressure is formally known by the term MAWP or Maximum Allowable Working Pressure. Of historical interest, this concept has existed for over 100 years, with the MAWP formula for cylindrical shells being tracable back to the original edition of the Boiler Code.

However, other variables in vessel design can also be optimized. In addition to pressure, consideration can be given to temperature or corrosion allowance. Increasing the temperature has the effect of reducing the basic allowable tensile stress as well as the allowable compressive stress and flange ratings. In the case of some specialty vessels such as reactors with exothermic reactions adding a few degrees to the design temperature may be very beneficial.

But virtually all vessels degrade in some manner, most often corrosion but sometimes via erosion or other degradation mechanisms. Significant amounts of time and effort are spent with unnecessary shutdowns, repairs, and / or fitness for service (FFS) evaluations all of which might have been avoided or deferred for years had the vessel originally been optimized for corrosion allowance. The term Maximum Allowable Corrosion Allowance or MACA is used to describe this approach.

This paper presents some arguments in favor of optimizing the corrosion allowance of pressure vessels, using a MACA based optimization for the design of new vessels rather than a pressure optimization or MAWP philosophy.

Copyright © 2016 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