Advertisement

Evaluation of Implicit Reliability Level Associated with Fatigue Design Criteria of Nuclear Class-1 Piping

  • J. Mishra
  • V. Balasubramaniyan
Conference paper
Part of the Lecture Notes in Mechanical Engineering book series (LNME)

Abstract

Fatigue design of Class-1 piping of NPP is carried out as par Section-III of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel code. The fatigue design criteria of ASME are based on the concept of safety factor, which does not provide means for management of uncertainties for consistently reliable designs. In this regard, a work is taken up to estimate the implicit reliability level associated with fatigue design criteria of Class-1 piping specified by ASME Section III, NB-3650. The methodology employed for reliability evaluation is FORM, HORSM and MCS, where limit state function is derived using mean fatigue curve developed by Argonne National Laboratory. A number of important aspects related to reliability of various piping product and joints are discussed, and implicit reliability level is evaluated.

Keywords

ASME Fatigue Implicit reliability FORM HORSM Piping 

Nomenclature

a

Constant term of polynomial

A, B, C

Constants of Langer equation

\( b_{ij} \)

Coefficients of univariate basis function

Cq

Coefficients of multivariate basis function

C1, C2

Secondary stress indices for the specific component under investigation

D

Expected accumulated damage ratio for the service life

\( D_{\text{o}} \)

Outside diameter of pipe

\( D_{f} \)

Cumulative damage ratio that leads to failure

\( f_{{X_{i,\ldots,n} }} (x_{i} , \ldots ,x_{n} ) \)

Joint probability density function of the random variables X i

\( F_{\text{en,nom}} \)

Nominal environmental fatigue correction factor

\( F_{\text{en}} \)

Factor on life due to environmental effects

\( F_{\text{se}} \)

Factor on life due to size effect

Fsf

Factor on life due to surface finish

Fdef

Factor on life due to conservatism in fatigue definition

\( g(X) \)

Limit state function

I

Moment of inertia

K1, K2

Peak stress indices

m, n

Material parameters

Mi

Resultant moment due to a combination of design mechanical loads

\( nb \)

Number of stress-range levels

\( n_{\text{eqv}} \)

Number of equivalent full temperature load cycles

N

Number of cycles

\( N_{\text{air,RT}} \)

Number cycle to failure in the air environment

\( N_{f} \)

Fatigue life or total number of cycles to failure

\( N_{fi} \)

Number of cycles to failure in ith stress-range level

\( N_{\text{water}} \)

Fatigue life in the water at service temperature

\( O^{\prime} \)

Transformed DO levels

\( P_{0} \)

Range of service pressure

\( P_{f} \)

Failure probability

\( R_{m} (x) \)

Regular polynomial

\( S_{a} \)

Alternating stress intensity

\( S_{m} \)

Allowable stress intensity value of the metal

\( S_{n} \)

Primary plus secondary stress intensity value

\( S_{p} \)

Peak stress intensity value

\( T^{\prime} \)

Transformed temperature

t

Nominal wall thickness of product

\( T_{m} (x) \)

Chebyshev polynomial

\( U_{i} \)

Usage factor at the ith stress-range level

\( X_{i} \)

Random variables

Z

Section modulus

\( \varepsilon_{a} \)

Alternating strain amplitude

\( \dot{\varepsilon}^{\prime} \)

Transformed strain rate

References

  1. 1.
    American Society of Mechanical Engineers (ASME), Rules for construction of nuclear facility components, ASME Boiler & Pressure Vessel Code (2010)Google Scholar
  2. 2.
    Gupta A, Choi B (2003) Reliability-based load and resistance factor design for piping: an exploratory case study. Nucl Eng Des 224:161–178CrossRefGoogle Scholar
  3. 3.
    Hill III RS (2004) Probabilistic & system—based methods for design—development of reliability-based load and resistance factor design methods for piping. ASME Nuclear Codes and Standards Workshop, New Orleans, LAGoogle Scholar
  4. 4.
    Chopra OK (2002) Mechanism and estimation of fatigue crack initiation in austenitic stainless steels in LWR environments, NUREG/CR-6787Google Scholar
  5. 5.
    American Society of Mechanical Engineers, Rules for construction of nuclear facility components. ASME Boiler and Pressure Vessel Code, Section-III, Appendix-I (2010)Google Scholar
  6. 6.
    Langer BF (1962) Design of pressure vessels for low-cycle fatigue. ASME J Basic Eng 84:389–402CrossRefGoogle Scholar
  7. 7.
    Chopra OK, Shack WJ (2007) Effect of LWR coolant environments on the fatigue life of reactor materials—final report, NUREG/CR-6909 and ANL-06/08Google Scholar
  8. 8.
    Chopra OK, Shack WJ (2003) Review of the margins for ASME code design curves—effects of surface roughness and material variability, NUREG/CR–6815, ANL–02/39Google Scholar
  9. 9.
    Chopra OK, Shack WJ (2001) Environmental effects on fatigue crack initiation in piping and pressure vessel steels, NUREG/CR–6717, ANL–00/27Google Scholar
  10. 10.
    Miner MA (1945) Cumulative damage in fatigue. J Appl Mech 12:A159–A164Google Scholar
  11. 11.
    Fatemi A, Yang L (1998) Cumulative fatigue damage and life prediction theories: a survey of the state of the art for homogeneous materials. Int J Fatigue 20(1):9–34CrossRefGoogle Scholar
  12. 12.
    Mishra J, Chellapandi P, MeherPrasad A, Narayanan S (2014) Evaluation of failure probability of expansion bellow at RCB containment penetration of PFBR using higher order response surface method. SRESA Int J Life Cycle Reliab Safety Eng 3(2):15–24Google Scholar
  13. 13.
    Avrithi K, Ayyub BM (2010) A reliability-based approach for low-cycle fatigue design of class 2 and 3 nuclear piping. J Press Vessel Technol 132Google Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Safety Research Institute, Atomic Energy Regulatory BoardKalpakkamIndia

Personalised recommendations