Alma Valor

Prof. Alma Valor

National Polytechnic Institute, Mexico (Instituto Politécnico Nacional)
orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2007 in Corrosion Science
Verified
Journal Article
Closed access
AVAlma Valor
Alma Valor
FCF. Caleyo
F. Caleyo
LAL. Alfonso
L. Alfonso
DRD. Rivas
D. Rivas
JHJ.M. Hallen
J.M. Hallen

1 September 2009 in Corrosion Science
Verified
Journal Article
Closed access
FCF. Caleyo
F. Caleyo
JVJulio C. Velázquez-Altamirano
Julio C. Velázquez-Altamirano
AVAlma Valor
Alma Valor
JHJ.M. Hallen
J.M. Hallen

1 May 2009 in Corrosion
Verified
Journal Article
Closed access
JVJulio C. Velázquez-Altamirano
Julio C. Velázquez-Altamirano
FCF. Caleyo
F. Caleyo
AVAlma Valor
Alma Valor
JHJ.M. Hallen
J.M. Hallen
A predictive model for pitting corrosion in buried pipelines is proposed. The model takes into consideration the chemical and physical properties of the soil and pipe to predict the time dependence of pitting depth and rate. Maximum pit depths were collected together with soil and pipe data at more than 250 excavation sites over a three-year period. The time dependence of the maximum pit depth was modeled as dmax = κ(t − t0)ν, where t is the exposure time, t0 is the pit initiation time, and κ and ν are the pitting proportionality and exponent parameters, respectively. A multivariate regression analysis was conducted with dmax as the dependent variable and the pipeline age, and the soil and pipe properties as the independent variables. The dependence of κ and ν on the predictor variables was found for the three soil textural classes identified in this study: clay, clay loam, and sandy clay loam. The proportionality parameter κ was found to be primarily influenced by the redox potential, pH value, soil resistivity, and the dissolved ion concentrations. In contrast, the pitting exponent ν was found to be influenced mainly by the pipe-to-soil potential, water content, bulk density, and the pipe coating type. A real-life pipeline integrity assessment is used as a case study to illustrate the application of the proposed model and to show how it can have a positive impact on integrity management programs.

1 September 2009 in Corrosion Science
Verified
Journal Article
Closed access
FCF. Caleyo
F. Caleyo
JVJulio C. Velázquez-Altamirano
Julio C. Velázquez-Altamirano
AVAlma Valor
Alma Valor
JHJ.M. Hallen
J.M. Hallen

1 January 2013 in Corrosion Science
Verified
Journal Article
Closed access
AVAlma Valor
Alma Valor
FCFrancisco Caleyo
Francisco Caleyo
JHJosé M. Hallen
José M. Hallen
JVJulio C. Velázquez-Altamirano
Julio C. Velázquez-Altamirano

1 November 2008 in Corrosion Science
Verified
Journal Article
Closed access
DRD. Rivas
D. Rivas
FCF. Caleyo
F. Caleyo
AVAlma Valor
Alma Valor
JHJ.M. Hallen
J.M. Hallen