1-20 of 394 Search Results for

life fraction rule

Follow your search
Access your saved searches in your account

Would you like to receive an alert when new items match your search?
Close Modal
Sort by
Image
Published: 01 January 2002
Fig. 15 Residual life predictions using the life fraction rule from increased stress and temperature tests for 1Cr-0.5Mo steel More
Series: ASM Handbook
Volume: 19
Publisher: ASM International
Published: 01 January 1996
DOI: 10.31399/asm.hb.v19.a0002390
EISBN: 978-1-62708-193-1
... Abstract The approaches to spectrum life prediction in components can be classified into two types, namely, history-based methods, using the life-fraction rule or other damage rules, and postservice evaluation methods. This article discusses the variables affecting the material crack growth...
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003517
EISBN: 978-1-62708-180-1
.... The article discusses metallurgical instabilities of steel-based alloys and nickel-base superalloys. It provides information on several life assessment methods, namely, the life fraction rule, parameter-based assessments, the thermal-mechanical fatigue, coating evaluations, hardness testing, microstructural...
Image
Published: 01 January 2002
(ductile) is a ductile tubing steel. (a) Correlation between expected life based on life fraction rule and the actually observed life in postexposure accelerated tests. (b) The expended life fraction under service conditions versus the remaining life fraction as determined from postexposure accelerated More
Image
Published: 01 January 2002
Fig. 33 Stress-rupture curves for virgin material and predamaged material showing the various life fractions. Virgin material rupture life at 575 °C (1065 °F) is 62,210 h Estimated remaining life at 575 °C (1065 °F) for predamaged samples based on: Symbol Damage fraction Life More
Image
Published: 01 January 2002
Fig. 32 Photograph of catastrophic fishmouth rupture of seam-welded high-energy piping. These failures are typically brittle and are not predicted using simple life fraction rule calculations. More
Series: ASM Handbook
Volume: 6
Publisher: ASM International
Published: 01 January 1993
DOI: 10.31399/asm.hb.v06.a0001477
EISBN: 978-1-62708-173-3
... assumed material properties and damage rules. The most widely applied creep-life fraction rule can be expressed as: (Eq 7) Σ t i t r = 1 where t i is the time spent at a given stress and temperature and t r is the rupture life for the same test conditions. When the damage...
Series: ASM Handbook
Volume: 20
Publisher: ASM International
Published: 01 January 1997
DOI: 10.31399/asm.hb.v20.a0002472
EISBN: 978-1-62708-194-8
... of temperature and stress on the extent of cracking at failure. Most theories assume that failure occurs at some critical cavity distribution or crack size. However, it has been shown that the extent of cavitation at failure or at any given fraction of the failure life is very sensitive to the test conditions...
Series: ASM Handbook
Volume: 19
Publisher: ASM International
Published: 01 January 1996
DOI: 10.31399/asm.hb.v19.a0002387
EISBN: 978-1-62708-193-1
... Abstract This article focuses on the subject of proactive or predictive maintenance with particular emphasis on the control and prediction of corrosion damage for life extension and failure prevention. It discusses creep life assessment from the perspective of creep-rupture properties...
Series: ASM Handbook
Volume: 8
Publisher: ASM International
Published: 01 January 2000
DOI: 10.31399/asm.hb.v08.a0003289
EISBN: 978-1-62708-176-4
..., performance often roughly follows the “life-fraction rule” or “linear cumulative damage rule” ( Ref 54 ), in which the percentage of total life consumed for each period of fixed temperature and stress is represented as: %   total life = actual time at the given conditions...
Series: ASM Handbook
Volume: 19
Publisher: ASM International
Published: 01 January 1996
DOI: 10.31399/asm.hb.v19.a0002365
EISBN: 978-1-62708-193-1
... on their manner of use and limitations. The use of the Palmgren-Miner rule for life prediction for variable amplitude loading is also discussed. fatigue life Palmgren-Miner rule strain-based approach stress-based approach variable amplitude load FATIGUE LIFE ESTIMATES are often needed...
Series: ASM Handbook
Volume: 11A
Publisher: ASM International
Published: 30 August 2021
DOI: 10.31399/asm.hb.v11A.a0006807
EISBN: 978-1-62708-329-4
... Abstract This article provides some new developments in elevated-temperature and life assessments. It is aimed at providing an overview of the damage mechanisms of concern, with a focus on creep, and the methodologies for design and in-service assessment of components operating at elevated...
Series: ASM Handbook
Volume: 20
Publisher: ASM International
Published: 01 January 1997
DOI: 10.31399/asm.hb.v20.a0002456
EISBN: 978-1-62708-194-8
... is then expressed in “design life fraction” using a company-specified design life, for example, 20 years. The 12 candidate materials are then ranked in order of decreasing life expectancy. A query for tube materials for a hypothetical location (with extremely polluted, sulfide-containing harbor water) resulted...
Series: ASM Handbook
Volume: 20
Publisher: ASM International
Published: 01 January 1997
DOI: 10.31399/asm.hb.v20.a0002451
EISBN: 978-1-62708-194-8
... Abstract This article provides an overview of cost analysis in materials selection. It discusses the several categories of alternatives for cost analysis. These include rules of thumb, accounting methods, and analytical methods. The article describes the methods for evaluating materials...
Series: ASM Handbook
Volume: 21
Publisher: ASM International
Published: 01 January 2001
DOI: 10.31399/asm.hb.v21.a0003382
EISBN: 978-1-62708-195-5
... incorporated into existing design practices. These models are simply applied to multistress-level loading and are traditionally associated with safelife. Palmgren-Miner Rule Perhaps the most simple life prediction model is the Palmgren- Miner rule ( Ref 27 , 28 ): (Eq 6) ∑ i = 1 m n...
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006462
EISBN: 978-1-62708-190-0
...-life and damage tolerant design approach is evident by contrasting Division 1 and Division 2 rules within Section VIII. But first a simple NDT method specific to pressure vessels is considered. Pressure vessels have an inherent NDT and SHM mechanism: if a crack pathway exists between the pressurized...
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003512
EISBN: 978-1-62708-180-1
... has elapsed. Calculations predict life exhaustion. Service time has reached some arbitrarily chosen fraction of calculated or experimental failure life. Previous failure statistics indicate high probability of failure. Frequency of repair renders continued operation uneconomical...
Series: ASM Handbook
Volume: 20
Publisher: ASM International
Published: 01 January 1997
DOI: 10.31399/asm.hb.v20.a0002487
EISBN: 978-1-62708-194-8
.... As with production machining systems, the general design-for-machining rules discussed in the next section of this article are broadly applicable to these systems. In CNC systems, however, the actual machining time consumes a smaller fraction of the total processing time. Reducing the time required for noncutting...
Series: ASM Handbook
Volume: 11A
Publisher: ASM International
Published: 30 August 2021
DOI: 10.31399/asm.hb.v11A.a0006802
EISBN: 978-1-62708-329-4
... elapsed. Calculations predict life exhaustion. Service time has reached some arbitrarily chosen fraction of calculated or experimental failure life. Previous failure statistics indicate high probability of failure. Frequency of repair renders continued operation uneconomical. Nondestructive...
Series: ASM Handbook
Volume: 11A
Publisher: ASM International
Published: 30 August 2021
DOI: 10.31399/asm.hb.v11A.a0006819
EISBN: 978-1-62708-329-4
..., Division 2, Alternate Rules for Pressure Vessels , followed in 1968 ( Ref 13 ). Section VIII, Division 1 of the ASME B&PV Code ( Ref 14 ), arguably one of the most widely used pressure vessel design codes for unfired and nonnuclear equipment, does not include explicit fatigue design life evaluation...