Coupled Electro-Chemical-Soil Model to Evaluate the Influence of Soil Aeration on Underground Metal Pipe Corrosion

CORROSION ◽  
10.5006/2860 ◽  
2018 ◽  
Vol 74 (11) ◽  
pp. 1177-1191 ◽  
Author(s):  
R.M. Azoor ◽  
R.N. Deo ◽  
N. Birbilis ◽  
J.K. Kodikara
Keyword(s):  
The United States ◽  
National Bureau ◽  
Iron Corrosion ◽  
Soil Aeration ◽  
Aeration Conditions ◽  
Underground Corrosion ◽  
Alloy Cast Iron ◽  
Evolution With Time ◽  
Macrocell Corrosion ◽  
Alloy Cast

A mechanistic understanding of the process of underground corrosion is important for modeling pipeline deterioration. In this study, a time-dependent multiscale numerical model incorporating electrochemistry and soil hydrology is developed. The model realistically simulates soil moisture and aeration conditions and their influence on anodic/cathodic activity without prior definition. In this manner, both micro- and macrocell corrosion and their evolution with time are simulated along with the effects of differential aeration. The model was validated with low-alloy cast iron corrosion data from the United States National Bureau of Standards corrosion exposure study. The effect of soil aeration in controlling soil corrosiveness was simulated with suitable boundary conditions. It was demonstrated that macrocells arising due to differential aeration can lead to elevated levels of corrosion in pipelines, especially in fairly aerated soils.

TYPE 1 NI-RESIST

Alloy Digest ◽  
1989 ◽  
Vol 38 (12) ◽  
Keyword(s):  
Cast Iron ◽  
Physical Properties ◽  
Heat Treating ◽  
Corrosion Resistant ◽  
Austenitic Alloy ◽  
Continuously Cast ◽  
Alloy Cast Iron ◽  
Alloy Cast

Abstract Type 1 Ni-Resist Dura-Bar is a corrosion resistant austenitic alloy cast iron, continuously cast. It has less than 10% alloy carbides, well dispersed and fine graphite flakes. It is non magnetic. This datasheet provides information on composition, physical properties, microstructure, and elasticity. It also includes information on heat treating. Filing Code: CI-60. Producer or source: Federal Bronze Products Inc..

Interest Rate, Foreign Exchange Rate, and Stock Market Development in Nigeria

2018 ◽  
Vol 9 (3) ◽  
pp. 247-253 ◽  
Author(s):  
Edward Adedoyin Adebowale ◽  
Akindele Iyiola Akosile
Keyword(s):  
Exchange Rate ◽  
Interest Rate ◽  
Stock Market ◽  
Foreign Exchange ◽  
The United States ◽  
Ordinary Least Squares ◽  
Foreign Exchange Rate ◽  
Market Development ◽  
National Bureau ◽  
Stock Market Development

This research investigated the effect of interest rate and foreign exchange rate on stock market development in Nigeria. This research was centered on two research problems. First, it was whether interest rate had a significant effect on stock market development in Nigeria. Second, it was whether foreign exchange rate had a significant impact on stock market development in Nigeria. The scope of the research covered the period from 1981 to 2017. Data for this period were chosen because it covered pre and post-liberalization periods of Nigerian financial system. This research made use of ex post facto research design. Secondary data were sourced from Nigerian Stock Exchange reports, Central Bank of Nigeria statistical bulletins, and National Bureau of Statistics publications. Data were collected on Stock Market Capitalization (SMC), Prime Lending Rate (PLR) and Real Exchange Rate (RER) (Nigerian Naira in relation to American Dollars of the United States). Data analysis was carried out with Ordinary Least Squares (OLS) and Cochrane-Orcutt Iterative techniques. The findings reveal that interest rate has a significant negative effect, and foreign exchange rate has a significant positive effect on Nigerian stock market development during the period covered. It is suggested that monetary authorities should strive to formulate policies that will make interest and foreign exchange rates stable, competitive, and at a level that will stimulate the investment of funds in the stock market.

Study on Friction Reduction and Anti-Scuffing Technology of Duplex Ion Nitrocarburizing and Sulphurizing

2008 ◽  
Vol 373-374 ◽  
pp. 476-479 ◽  
Author(s):  
C.H. Hu ◽  
Shi Ning Ma ◽  
Yu Lin Qiao ◽  
J.P. Zou ◽  
Y.D. Gao ◽  
...  
Keyword(s):  
Surface Layer ◽  
Diesel Engine ◽  
New Technology ◽  
Friction Reduction ◽  
Bench Test ◽  
Wear Volume ◽  
Engine Cylinder ◽  
Nitrocarburized Layer ◽  
Alloy Cast Iron ◽  
Alloy Cast

A new technology, duplex ion nitrocarburizing and sulphurizing technology (DINS), for friction reduction and anti-scuffing applications of diesel engine cylinder was studied. Duplex ion nitrocarburized-sulphurized layer was prepared on the surface of CrMoCu alloy cast iron by using the DINS process. The morphology, phase structure and tribological behaviors under sulphur contained additive lubrication were investigated. Results show that the sulphide surface layer of the duplex layer is mainly composed of close-packed hexagonal structured FeS phase and cubic structured FeS2 phase. The nitrocarburized sub-surface layer of the duplex layer is mainly composed of Fe2C and Fe3N phases. The harder nitrocarburized layer can provide effective support to the softer sulphide layer and avoid its lamellar tear. The synergistic effect between the duplex layer and the sulphur contained additive lubricant, resulted in 10% and 33.3% reduction in coefficient of friction and wear volume, respectively, compared with those of the sulphurized surface, and 25% and 50.1% reduction, respectively, compared with those of the plain surface. Bench test of diesel engine further demonstrated that the DINS process can provide the treated cylinder with superior properties in anti-scuffing and friction reduction, so that it can be used to prolong the service life of the cylinder.

Study on Plasma Arc Surface Hardening of Alloy Cast Iron

2012 ◽  
Vol 184-185 ◽  
pp. 1240-1243
Author(s):  
Ya Hui Wang ◽  
Bao Chen Ren ◽  
Ji Hong Yang
Keyword(s):  
Cast Iron ◽  
Surface Hardening ◽  
Technological Parameter ◽  
Orthogonal Test ◽  
Plasma Arc ◽  
Technological Parameters ◽  
Structure Condition ◽  
Surface Quenching ◽  
Alloy Cast Iron ◽  
Alloy Cast

Plasma arc was used as a heat source to make a surface quenching on alloy cast iron, and orthogonal test was used to optimize the surface hardening technological parameter of plasma arc. The influence of the technological parameters on hardness and depth of the hardening layer was analyzed, and the microhardness and the microscopic structure condition after being disposed were also analyzed and discussed.

Personal Reflections on the 1982 Special Anthropometric Issue of Social Science History

2004 ◽  
Vol 28 (2) ◽  
pp. 345-349 ◽  
Author(s):  
Stanley L. Engerman
Keyword(s):  
Social Science ◽  
Economic History ◽  
Local Population ◽  
Human Growth ◽  
The United States ◽  
National Bureau ◽  
Science History ◽  
Social Science History ◽  
Christopher Lasch ◽  
Personal Reflections

Looking back at the more than 20 years that have gone by since the 1982 special issue of Social Science History, it is interesting to observe how important the study of anthropometric data has been in contributing to economic history and related disciplines.While there had been numerous earlier comments by contemporary observers as well as by scholars about heights and their implications as seen in JamesTanner's marvelous study, A History of the Study of Human Growth (1981), the systematic work that was reflected in the 1982 volume was then only about six or seven years old in the United States. It represented the early output of a study directed by Robert Fogel, primarily through the Development of the American Economy (DAE) project of the National Bureau of Economic Research.There had been a few previous publications including my own piece in Local Population Studies (Engerman 1976). My first use of the height-by-age data was in response to a dinnerparty conversation in 1974 with two ofmy colleagues in the Rochester history department:Herbert Gutman and Christopher Lasch.

High-alloy cast iron, high-silicon cast iron

2011 ◽  
Author(s):  
Ruth Weidemann ◽  
Gundula Jänsch-Kaiser ◽  
David H. Sharp
Keyword(s):  
Cast Iron ◽  
High Alloy ◽  
High Silicon ◽  
Alloy Cast Iron ◽  
Alloy Cast

High-alloy cast iron, high-silicon cast iron

2011 ◽  
pp. NA-NA
Author(s):  
Karl Hauffe ◽  
Herbert Puschmann
Keyword(s):  
Cast Iron ◽  
High Alloy ◽  
High Silicon ◽  
Alloy Cast Iron ◽  
Alloy Cast
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