scholarly journals Determination the Corrosion Rate of Carbon Steel (0.4%C) Due to Thermal Cycling, Oil Cooled

2021 ◽  
Vol 65 (1) ◽  
pp. 74-78
Author(s):  
A.S.A. Elmaryami ◽  
Hafied M.B. Khalid ◽  
Abdulhakim Alamaria ◽  
Osama Alashebe ◽  
S.S. Ali ◽  
...  
Keyword(s):  
Steady State ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Thermal Cycling ◽  
Accurate Determination ◽  
Test Results ◽  
Heating And Cooling ◽  
Steel Bars ◽  
Lower Temperature

The effect of thermal cycling was carried out on steel bars (0.4 C %). A single run was performed at a lower temperature of 32℃ and an upper temperature of 500℃ cooled in water, seawater (previous results) and oil (new results). For several numbers of cycles up to 30 cycles for an accurate determination of heating and cooling times. The effect of thermal cycling on the corrosion rate was evaluated. The effect of thermal cycling on the following properties was evaluated the corrosion rate. The comparison between the effect of thermal cycling on carbon steel (0.4 C %) seawater and water-cooled (previous results as shown in references [1, 2]) and the effect of thermal cycling on carbon steel (0.4 C %) water-cooled (new results) has been studied. From the obtained test results (previous and in this paper, it was found that: the type of corrosion is uniform attack; corrosion rate of the first stage gradually increases with the number of thermal cycling up to 15 cycles, then it takes steady-state up to 30 cycles. It was found that the rate of corrosion (previous results, seawater and water-cooled) is more than the rate of corrosion of the new results, oil-cooled respectively.

scholarly journals Effect of Thermal Cycling on Corrosion Rate of Carbon Steel (0.4%C), Water Cooled

2020 ◽  
Vol 1 (1) ◽  
pp. 28-34
Author(s):  
Abdlmanam Elmaryami ◽  
Salem Ahmed Salem ◽  
Ali Saleh Saad ◽  
Mokhtar Hussien Omar ◽  
Khaled Rafaa Ali
Keyword(s):  
Carbon Steel ◽  
Corrosion Rate ◽  
Thermal Cycling ◽  
Sea Water ◽  
Accurate Determination ◽  
Test Results ◽  
Heating And Cooling ◽  
Steel Bars ◽  
Lower Temperature

The effect of thermal cycling was carried out on steel bars (0.4 %C). A single run was performed at a lower temperature of 320C and an upper temperature of 5000C cooled in water and seawater. For several numbers of cycles up to 30 cycles for an accurate determination of heating and cooling times. The effect of thermal cycling on the corrosion rate was evaluated. The effect of thermal cycling on the following properties was evaluated the corrosion rate. The comparison between the effect of thermal cycling on carbon steel (0.4% C) seawater cooled (previous results, sea-water cooled [1]) and the effect of thermal cycling on carbon steel (0.4 C %) (in this manuscript, water-cooled) has been studied. From the obtained test results (previous and in this paper, it was found that the type of corrosion is uniform, the corrosion rate of the first stage gradually increases with the number of thermal cycling up to 15 cycles, then it takes steady-state up to 30 cycles. It was found that the rate of corrosion (previous results, seawater cooled) is more than (the results in this paper, water-cooled).

scholarly journals Measurement Uncertainties Encountered During Gas Turbine Driven Compressor Field Testing

1998 ◽  
Author(s):  
Klaus Brun ◽  
Rainer Kurz
Keyword(s):  
Measurement Uncertainty ◽  
Gas Turbine ◽  
Field Test ◽  
Equations Of State ◽  
Accurate Determination ◽  
Field Testing ◽  
Significant Implication ◽  
Test Results ◽  
Measurement Uncertainties

Field testing of gas turbine compressor packages requires the accurate determination of efficiency, capacity, head, power and fuel flow in sometimes less than ideal working environments. Nonetheless, field test results have significant implication for the compressor and gas turbine manufacturers and their customers. Economic considerations demand that the performance and efficiency of an installation are verified to assure a project’s return on investment. Thus, for the compressor and gas turbine manufacturers, as well as for the end-user, an accurate determination of the field performance is of vital interest. This paper describes an analytic method to predict the measurement uncertainty and, thus, the accuracy, of field test results for gas turbine driven compressors. Namely, a method is presented which can be employed to verify the validity of field test performance results. The equations governing the compressor and gas turbine performance uncertainties are rigorously derived and results are numerically compared to actual field test data. Typical field test measurement uncertainties are presented for different sets of instrumentation. Test parameters that correlate to the most significant influence on the performance uncertainties are identified and suggestions are provided on how to minimize their measurement errors. The effect of different equations of state on the calculated performance is also discussed. Results show that compressor efficiency uncertainties can be unacceptably high when some basic rules for accurate testing are violated. However, by following some simple measurement rules and maintaining commonality of the gas equations of state, the overall compressor package performance measurement uncertainty can be limited and meaningful results can be achieved.

The Effect of the Partial Pressure of H2S and CO2 on the Permeation of Hydrogen in Carbon Steel by Using Pressure Buildup Techniques

CORROSION ◽  
10.5006/3128 ◽  
2019 ◽  
Vol 75 (10) ◽  
pp. 1207-1215
Author(s):  
Nayef M. Alanazi ◽  
Abdullah A. Al-Enezi
Keyword(s):  
Steady State ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Partial Pressure ◽  
Hydrogen Permeation ◽  
Measurement Techniques ◽  
Permeation Rate ◽  
Pressure Buildup ◽  
Hydrogen Flux ◽  
The Relationship

There are concerns in the industry about using an electrochemical technique for actual hydrogen permeation measurements where charging current is not a field condition. The objective of this work is to use pressure buildup techniques to study the influence of H2S and CO2 partial pressure on the relationship between hydrogen permeation and corrosion rate measured by different techniques. Sulfide films formed on carbon steel in a solution containing 5 wt% NaCl and 0.5 wt% acidic acid at various H2S and CO2 partial pressures were characterized, and the effect of the film on hydrogen permeation was also investigated. Field conditions were included in this study for comparison purposes. The relationship was modeled at the steady state of both hydrogen flux and corrosion rate. The results confirmed by use of two hydrogen flux measurement techniques (eudiometer and high-pressure buildup probe) and two corrosion measurement methods (weight loss coupons and coupled multiarray electrode system), that there is no direct correlation between hydrogen flux and corrosion rate. Therefore, the hydrogen permeation rate in H2S and CO2 environments was found to be more controlled by partial pressure of H2S than corrosion rate. The amount of descent in hydrogen flux, after reaching maximum of hydrogen permeation rate and before reaching a steady state, depends on the morphology and structure of corrosion films which are mainly controlled by concentration of H2S.

On Test Uncertainties in Field Performance Tests

2015 ◽  
Author(s):  
Rainer Kurz ◽  
Klaus Brun
Keyword(s):  
Measurement Uncertainty ◽  
Gas Turbine ◽  
Field Test ◽  
Measurement Errors ◽  
Equations Of State ◽  
Accurate Determination ◽  
Field Performance ◽  
Significant Implication ◽  
Test Results

Field testing of gas turbine or electric motor driven compressor packages requires the accurate determination of efficiency, capacity, head, or power consumption in sometimes less than ideal working environments. Nonetheless, field test results have significant implication for the compressor and gas turbine manufacturers and their customers. Economic considerations demand that the performance and efficiency of an installation are verified to assure the return on investment for the project. Thus, for the compressor and gas turbine manufacturers, as well as for the end-user, an accurate determination of the field performance is of vital interest. This paper discusses a method to determine the measurement uncertainty and, thus, the accuracy, of test results under the typical constraints of a site performance test, for compressors capable of variable speed operation. Namely, a method is presented which can be employed to verify the validity of field test performance results. Results are compared with actual field test results, using redundant methods. Typical field test measurement uncertainties are presented for different sets of instrumentation. The effect of different equations of state on the calculated performance is also discussed. Test parameters that correlate to the most significant influence on the performance uncertainties are identified and suggestions are provided on how to minimize their measurement errors. Results show that compressor efficiency uncertainties can be unacceptably high when some basic rules for accurate testing are violated. However, by following some simple measurement rules and maintaining commonality of the gas equations of state, the overall compressor package performance measurement uncertainty can be limited and meaningful results can be achieved.

Measurement Uncertainties Encountered During Gas Turbine Driven Compressor Field Testing

2000 ◽  
Vol 123 (1) ◽  
pp. 62-69 ◽  
Author(s):  
K. Brun ◽  
R. Kurz
Keyword(s):  
Measurement Uncertainty ◽  
Gas Turbine ◽  
Field Test ◽  
Equations Of State ◽  
Accurate Determination ◽  
Field Testing ◽  
Significant Implication ◽  
Test Results ◽  
Measurement Uncertainties

Field testing of gas turbine compressor packages requires the accurate determination of efficiency, capacity, head, power and fuel flow in sometimes less than ideal working environments. Nonetheless, field test results have significant implication for the compressor and gas turbine manufacturers and their customers. Economic considerations demand that the performance and efficiency of an installation are verified to assure a project?s return on investment. Thus, for the compressor and gas turbine manufacturers, as well as for the end-user, an accurate determination of the field performance is of vital interest. This paper describes an analytic method to predict the measurement uncertainty and, thus, the accuracy, of field test results for gas turbine driven compressors. Namely, a method is presented which can be employed to verify the validity of field test performance results. The equations governing the compressor and gas turbine performance uncertainties are rigorously derived and results are numerically compared to actual field test data. Typical field test measurement uncertainties are presented for different sets of instrumentation. Test parameters that correlate to the most significant influence on the performance uncertainties are identified and suggestions are provided on how to minimize their measurement errors. The effect of different equations of state on the calculated performance is also discussed. Results show that compressor efficiency uncertainties can be unacceptably high when some basic rules for accurate testing are violated. However, by following some simple measurement rules and maintaining commonality of the gas equations of state, the overall compressor package performance measurement uncertainty can be limited and meaningful results can be achieved.

scholarly journals DETERMINATION OF ATMOSPHERIC CORROSION RATE OF METALS IN 12 VIETNAMESE AREAS

2018 ◽  
Vol 55 (5B) ◽  
pp. 272
Author(s):  
Pham Duy Nam
Keyword(s):  
Carbon Steel ◽  
Corrosion Rate ◽  
Rural Areas ◽  
Atmospheric Corrosion ◽  
Climatic Factors ◽  
Air Pollutant ◽  
Climatic Data ◽  
Corrosion Rates ◽  
Copper Aluminum

The corrosion of materials is a result of complex impact from many climatic factors such as temperature, humidity, air pollutant content in the air, rainfall etc. In addition, the corrosion rate of metals can be measured. Each climatic zone is characterized by its corrosion rate. This article presents the testing results to determine the corrosion rate of carbon steel, copper, aluminum and zinc in 12 districts characterizing different climate zones of Vietnam. Testing, evaluation, and classification of atmospheric corrosion were conducted in accordance with the standard ISO 9223. The results show that for all types of studied metals, their corrosion rates which are determined from climatic data are higher than the corrosion rates in reality, especially for carbon steel and aluminum. This difference is more visible in the rural areas.

Improving quality of care and reducing costs with angiogenesis-specific imaging tests in metastatic breast cancer.

2012 ◽  
Vol 30 (34_suppl) ◽  
pp. 150-150
Author(s):  
Carolyn Bodnar ◽  
L. Clark Paramore ◽  
Kevin B. Knopf
Keyword(s):  
Breast Cancer ◽  
Quality Of Care ◽  
Metastatic Breast Cancer ◽  
Accurate Determination ◽  
Metastatic Breast ◽  
Base Case ◽  
Test Results ◽  
The Impact

150 Background: Anti-angiogenesis (AA) drugs (e.g., bevacizumab) are expensive and their clinical benefit in metastatic breast cancer (MBC) has been challenged. Healthcare reform and financial pressures prioritize programs which improve patient quality of care and reduce costs of unnecessary care. Angiogenesis-specific imaging tests (A-IT) under development have potential to offer earlier, accurate determination of response. For A-IT-identified responders, AA treatment would be continued. For patients identified as non-responders, futile AA treatment and associated toxicities can be avoided and alternative therapies initiated. Methods: A decision-tree model was developed to estimate the impact of A-IT from determination of AA therapy eligibility through to disease progression. Key decision nodes were presence/absence of A-IT (assessing change in biomarker expression across 2 PET/CT scans: at AA eligibility, then after one cycle of AA), A-IT sensitivity/specificity (SE/SP) and clinician adherence to test results (tied to belief that results are valid enough to stop AA therapy). Key model inputs (and base case values): 1) median time to progression (TTP) for current MBC patients on AA therapies (9.5 months); 2) median TTP for A-IT identified responders (13 months); 3) costs of bevacizumab, one cycle ($5,200); 4) percentage of AA patients with hemorrhage (4%); 5) costs of hemorrhaging, per event ($14,694); 6) per patient costs for A-IT ($6,000); 7) estimated SE/SP of A-IT – 95%/75%; and 8) clinician adherence to test results (75%). Results: Based on a cohort of 100 MBC patients, use of A-IT results in 29 patients avoiding futile AA therapy with a saving of $460,000, versus a scenario where A-IT was not used. One-way threshold sensitivity analysis shows A-IT is cost-saving if SP >62% or when clinician adherence is ≥63%; results are not sensitive to AA hemorrhage rate. Conclusions: Use of A-IT could improve quality of care by optimizing AA therapy, i.e., by identifying responders who will experience survival benefit and non-responders who can avoid futile therapy and toxicity risks. Significant cost savings may be possible as a result of early determination of response to AA drugs.

The Influence of Adding Bio Inhibitor Sarang Semut (Myrmecodia pendans) to Carbon Steel API 5L Grade B in Solution of HCl 1 M

2015 ◽  
Vol 1123 ◽  
pp. 187-191 ◽  
Author(s):  
Atria Pradityana ◽  
Sulistijono ◽  
Abdullah Shahab
Keyword(s):  
Carbon Steel ◽  
Corrosion Rate ◽  
Electrochemical Impedance ◽  
Rapid Development ◽  
Inhibition Mechanism ◽  
Test Results ◽  
X Ray Diffraction ◽  
Corrosive Media ◽  
Concentrate Level ◽  
Control Corrosion

Inhibitor is generally known as one of many alternatives to control corrosion rate. These days, there is the rapid development in which finding inhibitor made from natural ingredient that is really eco-friendly. This research use type of sarang semut, Myrmecodia Pendans (MP), as bio inhibitor with concentrate level for about 0-500 mg/L and also using the material of carbon steel API 5L Grade B, and HCl 1 M as such corrosive media. The affectivity of bio inhibitor is generally known through such calibration which is called as Weight Loss, Potentiodynamic Polarization Test, Electrochemical Impedance Spectroscopy Test, and X-Ray Diffraction Test. The test results show that when it is added with bio inhibitor, there is the decreasing of corrosion rate from 109.88 mpy to 39.294 mpy in concentration level of 500 mg/L. Inhibition mechanism occurred is that there is the formation of a thin layer on the metal surface. Meanwhile, the XRD results show that there are compounds of Fe, FeCl3 and FeOCl in carbon steel API 5l Grade B.

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