Ultrasonic monitoring of metal burn

2021 ◽  
pp. 477-480
Author(s):  
V.A. Erofeev ◽  
E.A. Strakhova
Keyword(s):  
Heat Treatment ◽  
Sound Wave ◽  
Ultrasonic Testing ◽  
Small Volume ◽  
Ultrasonic Monitoring ◽  
Metal Quality ◽  
Quality Estimation ◽  
Uneven Heating ◽  
Strong Scattering ◽  
Large Work

The problem of the metal quality estimation after heat treatment by which burn of the steel large work pieces is possible duе to the uneven heating of them in the furnaces is considered. The analysis of possibility to detect the burn zones during the ultrasonic testing by computer simulation of the passage of sound wave through the metal with many small defects is performed. Numerical solution of the wave equation showed that the strong scattering and the absorption of sound wave energy is observed when small volume of defects which is detected using receivers in the echo-method of ultrasonic testing. These receivers are installed on the work pieces surfaces perpendicular to the direction of the sound wave which allow to determine the location of the burned metal zone.

scholarly journals S55c Carbon Steel for Heat Treatment Process with Different Medium in Attenuation Measurement using Ultrasonic Testing

2018 ◽  
Vol 7 (4.35) ◽  
pp. 527
Author(s):  
Kharudin Ali ◽  
Johnny Koh Siaw Paw ◽  
M.Aizat M.Sulaiman ◽  
Ahmed N. Abdalla ◽  
Chong Kok Hen ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Carbon Steel ◽  
Ultrasonic Testing ◽  
Treatment Process ◽  
Excitation Frequency ◽  
Flaw Detection ◽  
Crack Identification ◽  
Heat Treatment Process ◽  
Attenuation Measurement ◽  
Quenching Process

Ultrasonic testing or commonly known as UT is one of the non-destructive testing technique and widely used in oil and gas industrial inspection. This technique mostly used in defect or crack identification of the pipeline and also used for flaw detection/evaluation, dimensional measurements, and material characterization. This paper presents the effect of heat treatment for S55C carbon steel in attenuation measurement by using ultrasonic testing including annealing, tempering, and quenching process.  Seawater and oil are used as a medium of quenching process. The fixed excitation frequency at 4 MHz is used and 0 degrees with double crystal is implemented in this measurement. The thicknesses of blocks used are as the sample from 30mm until 80mm. The result shows that the measurement of material attenuation will be decreased after annealing, tempering and quenching process from 40% until 99% compared to before the heat treatment process. The highest attenuation decreasing can be seen on the sample block with the 30mm thickness in the heat treatment process.  

scholarly journals Effect of the heat treatment mode of high chrome iron rolling mills on chrome redistribution in the stress field

2021 ◽  
pp. 113
Author(s):  
Olena Popova ◽  
Nataliia Lalazarova ◽  
Оlga Afanasieva
Keyword(s):  
Heat Treatment ◽  
Residual Stresses ◽  
Cooling Rate ◽  
Uniform Distribution ◽  
Temperature Difference ◽  
Thermal Stresses ◽  
Stress Gradient ◽  
Working Layer ◽  
Heating And Cooling ◽  
Uneven Heating

Heat treatment is an important stage in the technology of rolling rolls, due to the fact that the thermal stresses that occur during rapid or uneven heating summing up with the rather high residual stresses after casting, create a risk of cracking. Goal. The aim is improving the quality of rolling rolls by varying the modes of heat treatment. Therefore, it is important to assess the level of thermal stress. Method. Evaluation of thermal stresses arising in heating and cooling in the heat treatment process that summing up to the relatively high residual stresses after casting, creates the risk of fractures. The profile of the distribution of chromium in the cross section of the working layer at each time under the action of the stress gradient that occurs during heat treatment of the roll is obtained by calculation. Results To ensure a minimum temperature difference between the surface and the core, it is necessary to reduce the heating and cooling rate, as well as increase the duration of exposure at a given temperature. Reducing the cooling rate from 17 to 3.7°C/h decreases the temperature difference at the surface and in the center of the roll and the intensity of thermal stresses from 29 to 7 MPa. It is established that the rate of heating and cooling should not exceed 10– 15° C/h, and exposure to annealing should be at least 5–7 hours. Scientific novelty. The modes of heat treatment of rolling rolls with a high-chromium cast iron working layer are designed by estimating the level of thermal stresses. The profile of distribution of chromium after various modes of heat treatment is calculated analytically and its mode at which the most uniform distribution of chromium on section of a working layer remains is offered. Practical significance. The developed technique allows to calculate analytically the profile of distribution of chromium after various modes of heat treatment and to choose such a mode at which the most uniform distribution of chromium remains on the section of a working layer.

scholarly journals ОПТИМІЗАЦІЯ КОМПОЗИЦІЙНИХ ПЛАНІВ ЕКСПЕРИМЕНТУ МЕТОДОМ СТРИБАЮЧИХ ЖАБ

2020 ◽  
pp. 177-189
Author(s):  
Николай Дмитриевич Кошевой ◽  
Елена Михайловна Костенко ◽  
Виктор Владимирович Муратов
Keyword(s):  
Heat Treatment ◽  
Small Volume ◽  
Second Order ◽  
Computer Memory ◽  
Taboo Search ◽  
Methods Of Synthesis ◽  
Technical Systems ◽  
Optimization Of Composition ◽  
The Cost ◽  
Fast Acting

The second order composition plans are using for the construction of quadratic mathematical models of the probed objects and systems. The plans of the ortogonal central composition planning (OCKP) and rotatable central composition planning (RCKP) behave to them. As criteria of optimization of these plans, cost of experiment plan realization, its time of leading through have been chosen.The method and software for optimization in the cost and temporal expenses of second order composition plans with the use of spring-elastic frogs algorithm were developed. Software is realized in S++ language. All necessary calculations were executed on a computer with the processor of Intel Pentium G620 with frequency 2.60 Ghz. A necessary volume of memory is 26 Mb. Amount of factors and cost of factors levels transitions were entered with a keyboard, or set in a file.Realization of spring-elastic frogs method requires the small volume of computer memory and has a high fast-acting decision of task.The analysis of the known methods of synthesis of optimum on cost and temporal expenses composition the second order plans is conducted and its efficiency is rotined in comparison with the followings methods: swarm of particles, taboo-search, branches and scopes, progressive approximation. By developed method and software for optimization of composition the second order plans with the use of spring-elastic frogs’ algorithm it is possible to attain the high winnings as compared to the initial plan of experiment, optimum or near to optimum results by comparison to the methods of swarm of particles, taboo-search, branches and scopes, progressive approximation, and also high fast-acting of decision of task of optimization as compared to the methods of optimization developed before. The capacity of the developed method is tested at research of process of porous material heat treatment, and also modes of maintenance of the technical systems complex.It is proved that for optimization plans of OCKP and RCKP the use of spring-elastic frogs method is expedient. In future the results will be used for application of this method at research of the various technical systems.

Microstructure and Compressive Properties of Fe-Modified L12-TYPE Al3Ti

1990 ◽  
Vol 186 ◽  
Author(s):  
H.R. Pak ◽  
C.M. Wayman ◽  
L.H. Favrow ◽  
C.V. Cooper ◽  
J.S.L. Pak
Keyword(s):  
Crystal Structure ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Yield Stress ◽  
Single Phase ◽  
Small Volume ◽  
Volume Fraction ◽  
Small Region ◽  
Compressive Properties ◽  
Small Volume Fraction

AbstractThe microstructures and mechanical properties of an Fe-modified L12 alloy containing 7.5 at.% Fe have been investigated. This alloy has been determined to be essentially single phase following a homogenization heat treatment (HHT) at 1100°C for 100h, with a very small volume fraction of precipitates having been observed to form along dislocations. Conversely, in the case of the as-cast (AC) condition, the alloy has been determined to contain band-like precipitates, which have also formed along dislocations. In addition, a high density of very thin plate-like precipitates have formed parallel to {001} planes of the L12 matrix. Although these plate-like precipitates appear to exhibit lattice tetragonality, their crystal structure cannot be explained by assuming D022 and D023 structures. Five different <110>-type dislocations havfe been activated within a small region of a matrix grain during deformation at 1100°C, some of which cross slipped from {111} to {001} planes. Specimens in both AC and HHT conditions were deformed in compression to approximately 0.5% without fracture at both 22 and 1 100°C, the yield stress for the HIT condition having been determined to be 192 MPa at 22°C and 98 MPa at 1100°C.

Advanced SAWL Developments and Optimizations for High Toughness, Low Hardness and Sour Environment

2018 ◽  
Author(s):  
Fernando F. Silva ◽  
Fabio Arroyo ◽  
Philippe Darcis ◽  
Marcelo Fritz ◽  
Marcelo Salani ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Weld Metal ◽  
Ultrasonic Testing ◽  
Ultrasonic Inspection ◽  
Alloy Element ◽  
Metal Quality ◽  
Hydrogen Cracking ◽  
Welding Consumable ◽  
Welding Procedure

Natural gas exploitation has been increasing progressively and the pipeline community are facing more challenging demands to ensure safe and reliable operations. In that direction, gas fields in very harsh environments are demanding material and welding procedure selections to comply with a combination of important requirements such as toughness at low temperature, sour environment, very low hardness, manual ultrasonic inspection (for UOE longitudinal weld soundness assurance) and others. Looking forwarding big challenges, Tenaris Confab has been successfully working to continue improving the know how regarding plate to pipe mechanical properties behavior, through steel selection using TMCP plates, welding consumables definition and process control to assure material performance. Considering this scenario, the main challenge is to comply with a combination of toughness and hardness requirements, assuring the material soundness through manual ultrasonic testing after 48h. These combination lead to a careful selection of welding consumable to add the right content of alloy element at the welding pool aiming a specific weld metal chemical composition after dilution. The alloy element selection has to be considered due to the aimed final microstructure at the weld metal, i.e. increases acicular ferrite, in order to achieve the toughness, hardness and manual ultrasonic performance for delayed hydrogen cracking (DHC); it is important to avoid grain boundary ferrite (GBF) nucleation. High wall thickness and high heat input increases residual stress after pipe welding, high residual stress combined to poor microstructure and hydrogen, is a perfect scenario for DHC. To avoid hydrogen cracks, a robust pipe forming process and welding concept is needed to give enough energy to diffuse hydrogen out from weld metal. Quality controls were applied to strict hydrogen content such as welding consumable specifications, evaluating the correlation curve between flux moisture and diffusible hydrogen, flux temperature control and others. As a result of those actions, good mechanical properties were achieved and overcoming the hydrogen cracking performance during automatic and manual ultrasonic testing confirm a robust pipe forming and welding procedure for demanding projects.

Evaluation of Heat Treatment Effect on the Tensile Strength of Mild Steel Welded Joints Using Ultrasonic Testing

2021 ◽  
Vol 57 (6) ◽  
pp. 455-464
Author(s):  
Abid Shah ◽  
Ghazanfar Ali ◽  
Tariq Mairaj Rasool Khan ◽  
Aqueel Shah ◽  
Muhammad Imran ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Tensile Strength ◽  
Mild Steel ◽  
Treatment Effect ◽  
Welded Joints ◽  
Ultrasonic Testing

Protamine-DNA interaction

1978 ◽  
Vol 36 (2) ◽  
pp. 200-201
Author(s):  
D.P. Bazett-Jones ◽  
F.P. Ottensmeyer
Keyword(s):  
Small Volume ◽  
Double Helix ◽  
Dna Interaction ◽  
Dark Field ◽  
Sperm Head ◽  
Nuclear Proteins ◽  
Field Electron Microscopy ◽  
Dark Field Electron ◽  
Dna Double Helix ◽  
Positively Charged

Dark field electron microscopy has been used for the study of the structure of individual macromolecules with a resolution to at least the 5Å level. The use of this technique has been extended to the investigation of structure of interacting molecules, particularly the interaction between DNA and fish protamine, a class of basic nuclear proteins of molecular weight 4,000 daltons.Protamine, which is synthesized during spermatogenesis, binds to chromatin, displaces the somatic histones and wraps up the DNA to fit into the small volume of the sperm head. It has been proposed that protamine, existing as an extended polypeptide, winds around the minor groove of the DNA double helix, with protamine's positively-charged arginines lining up with the negatively-charged phosphates of DNA. However, viewing protamine as an extended protein is inconsistent with the results obtained in our laboratory.

The Theoretical Contrast in Scanning and Conventional High Resolution Microscopes

1969 ◽  
Vol 27 ◽  
pp. 170-171
Author(s):  
E. Zeitler ◽  
M. G. R. Thomson
Keyword(s):  
Small Volume ◽  
Volume Element ◽  
Optical Processing ◽  
Image Construction ◽  
Object Interaction ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Optical Treatment ◽  
Electron Microscopes ◽  
Intensity Contrast

In the formation of an image each small volume element of the object is correlated to an areal element in the image. The structure or detail of the object is represented by changes in intensity from element to element, and this variation of intensity (contrast) is determined by the interaction of the electrons with the specimen, and by the optical processing of the information-carrying electrons. Both conventional and scanning transmission electron microscopes form images which may be considered in this way, but the mechanism of image construction is very different in the two cases. Although the electron-object interaction is the same, the optical treatment differs.

The Precipitation of Si in AlCuSi Thin Films

1973 ◽  
Vol 31 ◽  
pp. 34-35 ◽  
Author(s):  
R. M. Anderson
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Heat Treatment ◽  
Solid Solution ◽  
Integrated Circuit ◽  
Copper Film ◽  
Solution Concentration ◽  
X Ray ◽  
Silicon Thin Films ◽  
Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

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