Modelling of Metal Loss in Ferromanganese Furnace Tapping Operations

Author(s):  
Quinn Gareth Reynolds ◽  
Jan Erik Olsen
Keyword(s):  
Author(s):  
Supriyadi Supriyadi

Pipa  penyalur  minyak  umumnya  menggunakan  material  baja  karbon.  Salah  satu  masalah  besar  dalam penggunaan material tersebut yang berkaitan dengan korosi yaitu terjadinya kebocoran akibat adanya pengaruh konsentrasi ion klorida yang terlarut dalam media air sehingga lingkungan bersifat korosif (asam). Oleh karena itu sebagai upaya untuk mengatasi masalah tersebut perlu diketahui besaran laju korosi material baja karbon tersebut. Dalam penelitian ini dilakukan perbandingan antara laju korosi yang diperoleh dari metode pengujian linear polarisasi resistance dan pengukuran metal loss dengan peralatan ultrasonic thickness meter. Output dari kedua metode tersebut selanjutnya diperoleh hubungan laju korosi melalui analysis of variance dengan menggunakan software. Studi pengaruh kadar klorida dilakukan untuk mengetahui korosi internal pipa baja karbon API 5L Grade B yang digunakan sebagai pipa penyalur minyak di lapangan. Metode pengujian polarisasi resistance dilakukan dalam media larutan air formasi NaCl 1%, 2% dan 3.5%. Laju korosi internal pipa baja karbon API 5L Grade B cenderung meningkat seiring dengan meningkatnya konsentrasi klorida dalam media larutan. Penelitian ini juga menunjukkan bahwa pipa baja karbon API 5L Grade B memiliki ketahanan korosi yang cukup pada fluida dengan konsentrasi klorida 1%, 2% dan 3.5%.


Author(s):  
Dmitry A. Neganov ◽  
◽  
Victor M. Varshitsky ◽  
Andrey A. Belkin ◽  
◽  
...  

The article contains the comparative results of the experimental and calculated research of the strength of a pipeline with such defects as “metal loss” and “dent with groove”. Two coils with diameter of 820 mm and the thickness of 9 mm of 19G steel were used for full-scale pipe sample production. One of the coils was intentionally damaged by machining, which resulted in “metal loss” defect, the other one was dented (by press machine) and got groove mark (by chisel). The testing of pipe samples was performed by applying static internal pressure to the moment of collapse. The calculation of deterioration pressure was carried out with the use of national and foreign methodical approaches. The calculated values of collapsing pressure for the pipe with loss of metal mainly coincided with the calculation experiment results based on Russian method and ASME B31G. In case of pipe with dent and groove the calculated value of collapsing pressure demonstrated greater coincidence with Russian method and to a lesser extent with API 579/ASME FFS-1. In whole, all calculation methods demonstrate sufficient stability of results, which provides reliable operation of pipelines with defects.


Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4811
Author(s):  
Siavash Doshvarpassand ◽  
Xiangyu Wang

Utilising cooling stimulation as a thermal excitation means has demonstrated profound capabilities of detecting sub-surface metal loss using thermography. Previously, a prototype mechanism was introduced which accommodates a thermal camera and cooling source and operates in a reciprocating motion scanning the test piece while cold stimulation is in operation. Immediately after that, the camera registers the thermal evolution. However, thermal reflections, non-uniform stimulation and lateral heat diffusions will remain as undesirable phenomena preventing the effective observation of sub-surface defects. This becomes more challenging when there is no prior knowledge of the non-defective area in order to effectively distinguish between defective and non-defective areas. In this work, the previously automated acquisition and processing pipeline is re-designed and optimised for two purposes: 1—Through the previous work, the mentioned pipeline was used to analyse a specific area of the test piece surface in order to reconstruct the reference area and identify defects. In order to expand the application of this device over the entire test area, regardless of its extension, the pipeline is improved in which the final surface image is reconstructed by taking into account multiple segments of the test surface. The previously introduced pre-processing method of Dynamic Reference Reconstruction (DRR) is enhanced by using a more rigorous thresholding procedure. Principal Component Analysis (PCA) is then used in order for feature (DRR images) reduction. 2—The results of PCA on multiple segment images of the test surface revealed different ranges of intensities across each segment image. This potentially could cause mistaken interpretation of the defective and non-defective areas. An automated segmentation method based on Gaussian Mixture Model (GMM) is used to assist the expert user in more effective detection of the defective areas when the non-defective areas are uniformly characterised as background. The final results of GMM have shown not only the capability of accurately detecting subsurface metal loss as low as 37.5% but also the successful detection of defects that were either unidentifiable or invisible in either the original thermal images or their PCA transformed results.


Author(s):  
Giorgio G. J. Achterbosch ◽  
Gerard A. J. Stallenberg

A substantial part of the high pressure gastransport network of Gastransport Services as part of N.V. Nederlandse Gasunie in the Netherlands is not piggable. It is therefore foreseen that an ECDA approach including coating survey techniques, CP measurements and bell hole excavations, will be implemented to establish the integrity of these non-piggable lines. In order to get a better understanding of the performance of some techniques for our specific situation, a test program was carried out on a pipeline of 33 kilometres with a diameter of 8” and bitumenous coating, constructed in the sixties. DCVG, Pearson and a combination of CIPS and Pearson (CIPP) were tested in combination with 3 MFL intelligent pigruns, current attenuation measurements by the Stray Current Mapper (SCM) and bell hole excavations. Initial results for the three coating survey techniques showed that the detection probabilities for a coating defect ranged from 18% to 68% under the assumption that no false calls were generated. Using results from repeat measurements and taking into account the possibility of false calls, the detection probabilities increased to potential maximum values of 48% to 94%. Better estimations of the values could be obtained after verification of some indications from CIPP, leading to maximum values in the range of 70% to 84% for the best two techniques. Additional measurements at pre-selected locations by means of pipe-to-soil-potentials and pin-current measurements did not indicate active corrosion. Verification excavations at 14 locations indicated that in all situations a coating defect existed and that mild general corrosion was present in eight situations due to the very aggressive soil (soil resistances of several Ωm’s were measured). Current attenuation measurements by the SCM suggested a uniform distribution of coating quality. The results from the three intelligent pigruns were of relatively little use because of the detection threshold of 15% wall thickness and the fact that the suppliers often did not agree on the interpretation of metal loss. Therefore the results could not be considered to be an absolute true reference for relating the coating defects to. Although the results of the program gave very valuable insight into the characteristics of the different techniques it is recognized that not all results can be translated to other circumstances/pipelines. Therefore additional tests and surveys will be carried out in the coming year(s) to further work out the ECDA procedure for the specific situation of the non-piggable pipelines of Gastransport Services.


Author(s):  
Lucinda Smart ◽  
Richard McNealy ◽  
Harvey Haines

In-Line Inspection (ILI) is used to prioritize metal loss conditions based on predicted failure pressure in accordance with methods prescribed in industry standards such as ASME B31G-2009. Corrosion may occur in multiple areas of metal loss that interact and may result in a lower failure pressure than if flaws were analyzed separately. The B31G standard recommends a flaw interaction criterion for ILI metal loss predictions within a longitudinal and circumferential spacing of 3 times wall thickness, but cautions that methods employed for clustering of ILI anomalies should be validated with results from direct measurements in the ditch. Recent advances in non-destructive examination (NDE) and data correlation software have enabled reliable comparisons of ILI burst pressure predictions with the results from in-ditch examination. Data correlation using pattern matching algorithms allows the consideration of detection and reporting thresholds for both ILI and field measurements, and determination of error in the calculated failure pressure prediction attributable to the flaw interaction criterion. This paper presents a case study of magnetic flux leakage ILI failure pressure predictions compared with field results obtained during excavations. The effect of interaction criterion on calculated failure pressure and the probability of an ILI measurement underestimating failure pressure have been studied. We concluded a reason failure pressure specifications do not exist for ILI measurements is because of the variety of possible interaction criteria and data thresholds that can be employed, and demonstrate herein a method for their validation.


Author(s):  
Ali Keshavarz ◽  
Andrew K. Ali ◽  
Randy K. Lall

Flow-accelerated corrosion (FAC) is a phenomenon that results in metal loss from piping, vessels and equipment made of carbon steel. This metal loss can lead to stress to occur at the steam inlet nozzle side, where it is located at the side of the deaerator. This paper presents a method to find the thickness critical of the steam inlet nozzle. A Finite Element (FE) model of the pressure vessel head was created to perform a stress analysis using NX Nastran 5.0. By applying materials properties, loads and constraints to the model, the results obtained are required to satisfy the following criterion: vonMises≥SySy=YieldStrength The results obtained from the stress analysis were analyzed to obtain a corrosion allowance and it was compared to the recommended value from a normal deaerator design, which is roughly 0.25 inches. From the FE model, and by continuously reducing the thickness of the nozzle, it was determined that the corrosion allowance is 0.229 inches, and that the percentage error was 8.4%.


Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3862
Author(s):  
Qiuping Ma ◽  
Guiyun Tian ◽  
Yanli Zeng ◽  
Rui Li ◽  
Huadong Song ◽  
...  

Pipelines play an important role in the national/international transportation of natural gas, petroleum products, and other energy resources. Pipelines are set up in different environments and consequently suffer various damage challenges, such as environmental electrochemical reaction, welding defects, and external force damage, etc. Defects like metal loss, pitting, and cracks destroy the pipeline’s integrity and cause serious safety issues. This should be prevented before it occurs to ensure the safe operation of the pipeline. In recent years, different non-destructive testing (NDT) methods have been developed for in-line pipeline inspection. These are magnetic flux leakage (MFL) testing, ultrasonic testing (UT), electromagnetic acoustic technology (EMAT), eddy current testing (EC). Single modality or different kinds of integrated NDT system named Pipeline Inspection Gauge (PIG) or un-piggable robotic inspection systems have been developed. Moreover, data management in conjunction with historic data for condition-based pipeline maintenance becomes important as well. In this study, various inspection methods in association with non-destructive testing are investigated. The state of the art of PIGs, un-piggable robots, as well as instrumental applications, are systematically compared. Furthermore, data models and management are utilized for defect quantification, classification, failure prediction and maintenance. Finally, the challenges, problems, and development trends of pipeline inspection as well as data management are derived and discussed.


2021 ◽  
Vol 1037 ◽  
pp. 281-286
Author(s):  
Sergey Nikolaevich Larin ◽  
Nikita A. Samsonov

Plastic forming, in many cases, includes the drawing of hollow cylindrical products as the main operation. For the manufacture of such products, round blanks are used as semi-finished products. However, during the blank production from strips or tapes, their geometry causes a very significant metal loss. A very effective way to reduce metal loss is to replace round billets with square ones. The use of square blanks gives an additional increase in the height of the products. In this regard, the article investigates the drawing of a square blank into a cylindrical die. The research was carried out on the basis of the analysis of experimental work and computer modeling. According to the results of the research the rational ratios of the geometric dimensions of the tool and workpieces are found.


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