Methodology for Vintage Pipelines Assessment

2012 ◽  
Author(s):  
Mélissandre Phelippon ◽  
Stéphane Hertz-Clemens ◽  
Philippe Notarianni
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Chemical Composition ◽  
Sulfur Content ◽  
Parent Material ◽  
International Standards ◽  
Composition Analysis ◽  
Line Pipe ◽  
Test Pieces ◽  
Chemical Composition Of Steel

During inspection and maintenance operations, pipeline operators may encounter pipes showing incomplete records. However, data such as pipe tensile properties and toughness are essential to perform a realistic pipeline fitness for service analysis. These situations most often occur with older pipelines, in a period where line pipe quality control and quality assessment were not as stringent as today. In order to avoid a cut and a replacement of the pipe, introducing transit interruption and high expenses for the operator, a methodology for determining mechanical properties has been developed. The methodology described in this paper relies on data obtained from many tests performed on this specific type of line. The study and analysis of these database information led to working out correlations between parameters measured on field, and missing recorded mechanical properties. The first data that can be obtained quite easily is the chemical composition of steel, which can be analyzed in a laboratory from samples directly removed from parent material of the line pipe. Using the result of the previous analyses, the following correlations have been determined from the database information, and have been compared to correlations given in international standards (API 579, BS7910,…): - Charpy V energy measured at 0°C versus Charpy U energy pleasured at 20°C, - Charpy V energy versus sulfur content, - Fracture toughness versus Charpy V energy, - Fracture toughness versus sulfur content. A practical experiment of these results have been performed, as chemical composition analysis from samples were made on 5 removed test pieces issued from line pipes. These tests aimed at comparing the results given by correlations with the mechanical properties of the line pipes, and validating the feasibility of this methodology on the field. At the same time, database information was also used to check the theoretical behavior of parent metal regarding to the design temperature, by using a relation between steel toughness value, and its transition temperature at 28 J, issued from toughness transition curves.

scholarly journals Electroless Ni-P Coatings: Preparation and Evaluation of Fracture Toughness and Scratch Hardness

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Wagner Sade ◽  
Reinaldo Trindade Proença ◽  
Thiago Daniel de Oliveira Moura ◽  
José Roberto Tavares Branco
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Chemical Composition ◽  
Scratch Hardness ◽  
Hard Particles ◽  
Steel Aisi ◽  
Electroless Ni ◽  
Preparation And Evaluation ◽  
Phase Relationships ◽  
Thermally Treated

Ni-P chemical coatings have been used to prevent wear, corrosion and as an alternative for hard chromium, since the latter's deposition processing is very harmful to the human health and the environment. In the present paper, Ni-P coatings with 8 and 10% P were deposited in steel AISI 1020 and thermally treated. Ni-1wt%P coatings with incorporation of hard particles of Al2O3 were also investigated. The microstructure and phase relationships were analyzed and correlated with the fracture toughness and scratch hardness of the coatings.The results show that the fracture toughness of the coating was smaller when thermally treated at 400°C for 1 hour and the scratch hardness reached a peak in this temperature. The relation of chemical composition and microstructure with mechanical properties of Ni-P coatings is presented. The phosphorus contents, the crystallization, and the incorporation of hard particles in the coatings change the values of toughness fracture and scratch hardness.

Mechanical Properties of α- and β-SiAlON Composite Ceramics Using β-SiAlON Powder

2008 ◽  
Vol 403 ◽  
pp. 111-114 ◽  
Author(s):  
Kei Asakoshi ◽  
Junichi Tatami ◽  
Katsutoshi Komeya ◽  
Takeshi Meguro ◽  
Masahiro Yokouchi
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Rare Earth ◽  
Chemical Composition ◽  
Metal Oxides ◽  
Bending Strength ◽  
Rare Earth Oxide ◽  
Composite Ceramics ◽  
Oxide Powders ◽  
Sialon Powder

β-SiAlON powder was used as a raw powder to fabricate α/β-SiAlON composite ceramics with different rare earth elements. The phases present in the sample fabricated from -SiAlON, α-Si3N4, AlN, and rare earth oxide powders were - and -SiAlONs. The composition was dependent on the chemical composition and firing profile. The sample obtained by adding Yb2O3 had a high -SiAlON content. The /-SiAlON composite ceramics had high densit. Their microstructures depended on the used metal oxides, namely, the addition of Nd2O3 and CaCO3 resulted in the elongation of the -SiAlON grains. The bending strength, fracture toughness, and hardness were influenced by the -SiAlON content, amount of elongated grains, and density of the sample.

scholarly journals Analysis and Research on the Cause of Wind Turbine Blade Bolt Fracture

2021 ◽  
Vol 2133 (1) ◽  
pp. 012028
Author(s):  
Feng Yun ◽  
Jun Liu ◽  
Chunyu Liu ◽  
Xiaochun Zhao
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Stress Concentration ◽  
Wind Turbine ◽  
Turbine Blade ◽  
Wind Farm ◽  
Composition Analysis ◽  
Chemical Composition Analysis ◽  
Mechanical Properties Testing ◽  
Load Impact

Abstract In 2019, inspection personnel of a wind farm went to the tower and found that a total of 6 bolts of blades in the hub of a wind turbine had broken and failed. In order to find out the cause of fracture, the fracture bolt was comprehensively detected and analyzed by means of appearance morphology analysis, chemical composition analysis, mechanical properties testing, microstructure testing and fracture micro-area analysis. The results show that the main reasons for the bolt fracture are as follows: under the action of the bolt’s constantly changing and repeated wind load impact and the alternating load caused by blade rotation during the operation of the fan, the crack source is formed along the bottom of the thread with serious stress concentration and expands in fatigue mode until the whole fracture fails.

Strain Aging Effects in High Strength Line Pipe Materials

2008 ◽  
Author(s):  
Da-Ming Duan ◽  
Joe Zhou ◽  
Brian Rothwell ◽  
David Horsley ◽  
Nick Pussegoda
Keyword(s):  
Mechanical Properties ◽  
Strain Aging ◽  
Mechanical Test ◽  
High Strength ◽  
Parent Material ◽  
Pipe Material ◽  
Aging Effects ◽  
Aging Behavior ◽  
Test Procedures ◽  
Line Pipe

Strain aging behavior can occur in almost all steels, including micro-alloyed steels used in high-strength pipelines. The direct effects of strain aging on mechanical properties can include increased hardness, yield strength and tensile strength, and reduced ductility and toughness. Strain aging may take place in processes where the pipe material experiences thermal cycles, such as coating, welding and in-service heating, and may occur with or without additional plastic strain. The changes of material mechanical properties could seriously challenge the design principles and methodologies, so that these aging effects need to be taken into account. This is especially important for pipelines expected to see deformation-controlled loading conditions. This is not only because the difference in strain aging effects between a weld and the parent material can easily change the strength overmatch condition of the weld, leading to unpredictable girth weld flaw tolerance, but also because the return of Lu¨ders behavior on the stress-strain curves of these materials significantly reduces the pipe buckling load resistance. In addition, any change in fracture resistance due to strain aging may impact the fracture control design practice, particularly if the pipe material may be expected to experience plastic deformation during service. In this paper, a brief review of strain aging behavior in steels is presented, with an emphasis on the effects on the mechanical properties and toughness of three high-strength line pipe steels. Material strain aging mechanical test procedures of three high grade pipes will be described and the test results will be discussed.

The Effect of Low Sulfur Content on the Weldability of Linepipe Steel

2012 ◽  
Author(s):  
Kimberly K. Cameron ◽  
Alfred M. Pettinger
Keyword(s):  
Fracture Toughness ◽  
Sulfur Content ◽  
Large Scale ◽  
Pipeline Steel ◽  
Active Agent ◽  
High Strength ◽  
Pipeline System ◽  
Line Pipe ◽  
Low Sulfur ◽  
Linepipe Steel

Over time, the demand for high-strength linepipe has increased significantly. One of the challenges for developing higher strength linepipe has been maintaining an appropriate level of fracture toughness, yield to tensile strength ratio, and weldability. Fortunately, significant progress has been made in the production of high strength line pipe steel. A major improvement in steel making has been the utilization of secondary steel treatments to refine the steel and accurately control alloy additions to achieve a higher level of steel cleanliness. In particular, these refining treatments have enabled the achievement of extremely low sulfur levels. For most purposes, restricting sulfur content is desirable to help prevent a reduction in mechanical properties such as fracture toughness of the steel. Fortunately, steelmaking and desulfurization technologies have advanced to the point where pipeline steel with sulfur contents less than the requirements by API 5L are available on a large scale. Extremely low sulfur contents, however, can lead to other problems when welding steels. These weldability problems are related to the fact that sulfur is a known surface active agent for steels. Low sulfur concentrations lead to a reversal of the Marangoni convection in the weld pool, which is responsible for the large differences in weld penetration on otherwise identical steels. Additionally, when welding heats of unmatched sulfur concentrations, the arc will tend to deviate towards the low sulfur heat and axially shift the root of the weld if one of the heats was below a critical value for the sulfur content and the other was above this value. Although this phenomenon has been primarily observed in stainless steels, the increasing ability to produce linepipe steel with extremely low sulfur contents has led to the possibility that this phenomenon could also occur in low carbon pipeline steels. One pipeline system utilizing cellulosic consumables for shielded metal arc welding (SMAW) of X70 steel with sulfur contents an order of magnitude below that permitted by API 5L and with widely varying sulfur contents shows evidence of this effect. The profiles of the welds in this system exhibited a tendency for lack of penetration, asymmetric weld roots, and concave welds. One approach to ameliorate this would be the specification of a lower permissible amount of sulfur.

scholarly journals Effect of Alkali Seepage Erosion on Physical and Mechanical Properties of Laterite

2021 ◽  
Vol 2021 ◽  
pp. 1-10 ◽  
Author(s):  
Yan Li ◽  
Yasheng Luo ◽  
Songtao Hu ◽  
Jianglin Gao ◽  
Chaojie Wang
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Alkaline Solution ◽  
Physical And Mechanical Properties ◽  
Solution Concentration ◽  
Composition Analysis ◽  
Minor Effect ◽  
Strength Parameters ◽  
Soil Particles ◽  
Corrosion Time

Using a modified permeameter, laterite samples that were corroded and permeated by alkaline solutions at different concentrations for varying amounts of time were subjected to triaxial compression tests, chemical composition analysis, particle composition tests, and microstructure analysis. The results showed that the strength parameters c, φ, and K of the laterite samples that were corroded by alkaline-solution permeation were reduced with increasing corrosion time and alkaline-solution concentration. The alkaline-solution corrosion had a minor effect on the strength parameters n and Rf. The contents of Al2O3 and Fe2O3 in the laterite fluctuated and decreased with increasing alkaline-solution concentration and corrosion time. There were no distinct patterns in the relationships between the SiO2 content and the increases in the alkaline-solution concentration and corrosion time. Due to the corrosion during the alkaline-solution permeation, the content of clay particles increased with increasing time and concentration of the alkaline solution. After the permeation with the alkaline solution, the soil particles became smaller and were arranged in an ordered state. The analysis suggested that the permeation effect of the alkaline solution changed the chemical composition of the laterite and the connecting strength of the soil particles, resulting in changes in its physical and mechanical properties.

Age-Related Changes in Structure, Composition and Mechanical Properties of Swine Cortical Bone

2009 ◽  
Author(s):  
Liang Feng ◽  
Rohit Bhargava ◽  
Iwona Jasiuk
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Chemical Composition ◽  
Bone Structure ◽  
Experimental Methods ◽  
Biological Processes ◽  
Age Related ◽  
Open Question ◽  
Age Related Changes ◽  
Comprehensive Study

Bone has a complex hierarchical structure spanning from nanometer to macroscopic dimensions. We apply several experimental methods at different structural scales to study the three fundamental aspects of this material: the structure, composition and mechanical properties. As a biological material, bone is constantly under development. These biological processes such as remodeling and aging are known to increase the susceptibility of bone to fracture. The age-related changes in the fracture toughness and other mechanical properties are manifested by the alteration of the bone structure and chemical composition [1]. Various studies addressed the changes in bone’s structure, composition and mechanical properties due to aging [2–5]. However, these studies were confined to only one or two of these aspects, separately. So there is still an open question about how these three aspects are correlated with each others. Thus, a comprehensive study is needed to address it.

Metallurgical analysis of the causes of failure of the hardening furnace conveyor belt

2019 ◽  
Vol 2 (98) ◽  
pp. 68-73
Author(s):  
A. Merda ◽  
K. Klimaszewska ◽  
M. Sroka ◽  
G. Golański
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Austenitic Steel ◽  
Sigma Phase ◽  
Conveyor Belt ◽  
Composition Analysis ◽  
Microstructure And Mechanical Properties ◽  
Metallurgical Analysis ◽  
M23c6 Carbides ◽  
Causes Of Failure

Purpose: The aim of the tests was to analyze the microstructure and mechanical properties of a section of the hardening furnace conveyor belt serviced at the temperature of 880-920°C in the carburizing atmosphere, in the context of determining the probable causes of its failure. Design/methodology/approach: The scope of performed tests included: chemical composition analysis of the steel and particles, microstructure investigated using optical and scanning electron microscopy, X-ray phase analysis. Findings: The analysis of the chemical composition showed that the examined material was austenitic steel X15CrNiSi25-21 (S310). Performed metallurgical tests showed that after the service the examined steel was characterized by austenitic structure with numerous precipitates of diverse morphology. In the structure the sigma phase particles and probably the M23C6 carbides precipitates were observed. The continuous grid of precipitates on the boundaries of grains (mainly the sigma phase) and the influence of the cyclic changing heat loads (or thermo-mechanical loads) were the main causes of failure of the analysed detail. Research limitations/implications: The aim of the work was to determine the probable causes of damage of the material used for a conveyor belt of a hardening furnace. Practical implications: The results of investigation and analysis of the metallographic of het-resisting austenitic steel X15CrNiSi25-21 (S310) after service at the temperature of 880-920°C are presented. Originality/value: The paper presents the results of research on the microstructure and mechanical properties of the section of hardening furnace conveyor belt made of creepresisting austenitic steel. The aim of the performed tests was to determine the probable causes of damage of the analysed detail.

scholarly journals Analysis and Harmonization of National and International Quality Standards for Compacted Graphite Cast Irons

2020 ◽  
pp. 88-95
Author(s):  
Alena Kropivna ◽  
◽  
Olexandr Kuzyk ◽  
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Chemical Composition ◽  
Quality Indicators ◽  
International Standards ◽  
National Standards ◽  
National Standard ◽  
High Quality ◽  
Foundry Industry ◽  
European Standards

Ensuring and coordination of high quality indicators of materials in the foundry industry is necessary in the development of Ukraine's economy. High quality products need to be enshrined in new national standards, harmonized with international and European standards. Thus, the purpose of this work is to analyze national and international standards for quality indicators of vermicular graphite iron and their harmonization with each other. The foundry industry of Ukraine has developed mainly with the use of interstate standards - GOST, which differ significantly from European and international and requires coordination and other approaches to the development of new standards. Today there are a number of international standards: ISO, SAE, CEN, VDG, ASTM, JIS, GB, STAS, which regulate the properties of cast iron with vermicular graphite. Most standards define the range of permissible content of spherical graphite (0… 20%) in the structure of cast iron with vermicular graphite, as well as determine the shape of samples to determine the properties and provide for the determination of graphite on surfaces formed after machining castings. In accordance with the needs of the automotive industry, the Society of Automotive Engineers (SAE) has created the standard SAEJ1887 JUL2002 for cast iron with vermicular graphite. The DSTU standard in force in Ukraine regulates only the temporary resistance to tensile and elongation laid down in the brand designation. Thus, the improvement, provision and harmonization of the national standard at the vermicular graphite iron by achieving high quality indicators of materials in the foundry industry, will ensure the stability of the technological production process, and further entry into international and European markets and a qualitatively new level of domestic engineering. An analysis of the current standards in Ukraine DSTU for cast iron with vermicular graphite is given, as well as its regulated mechanical properties and recommended chemical composition. The properties of similar international and European standards for cast iron with vermicular graphite according to ISO, SAE, CEN, VDG, ASTM, JIS, GB, STAS standardization are analyzed, as well as cross-references to ISO 16112 to other standard brands of the vermicular graphite iron. The conformity of brands of materials, depending on their chemical composition and mechanical properties given in GOST, international and European indicators is found out.

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