Industrial Piping Research Articles

Robust metamodels for accurate quantitative estimation of turbulent flow in pipe bends

Pipe bends are inevitable in industrial piping systems, turbomachinery, heat exchangers, etc. Computational fluid dynamics (CFD), which is commonly employed to understand the flow behavior in such systems has very accurate estimation but is computationally cost intensive. Thus, in this paper, an efficient computational approach for such computationally expensive problems is presented. Using genetic programming (GP), metamodels are built using a small number of samples points from the CFD data. These GP metamodels are then shown to be able to replace the actual CFD models with considerable accuracy. The applicability and suitability of the GP metamodels are validated using a variety of statistical metrics on the training as well as independent test data. It is shown that the use of metamodels leads to significant savings in computational cost.

On the reciprocating sliding wear of polypropylene against polyamide 6 in dry and aqueous environments

Polymer-polymer tribological components with sliding contacts usually are lighter, cheaper and more corrosion resistant in aqueous environment, presenting some advantages over the classic metal-polymer equivalents under certain conditions, such as in wear resistant external coatings for pipes in industry. Reciprocating sliding wear of polypropylene (PP) against polyamide 6 (PA6) in dry and aqueous environments (distilled water and synthetic sea water) was mapped as a function of contact pressure (2.4–7.2 MPa) and sliding speed (36–108 mm/s), aiming the identification of favorable operating conditions (low wear). Mild wear regime (k = 1.3–5.3 × 10−6 mm3/N m) was found for PP in all conditions, except for the highest sliding speed in dry environment, where there was a severe regime (k = 0.5–0.8 × 10−3 mm3/N m). Meanwhile, the PA6 counter-body always operated in the mild wear regime for all studied conditions. Wear mechanisms in the mild regime were: surface fatigue microcracks, film transfer and abrasion for both materials and, for PA6 only, also wear by roll formation. At higher speed, frictional heating (0.14 < μ < 0.25) and low thermal diffusivity of the materials resulted in high contact temperatures (up to 120 °C), which is enough to promote the removal of molten or softened material in the PP, typical of severe wear regime. The mild-to-severe wear regime transition observed for PP-PA6 tribopair occurs at a much lower sliding speed than in metal-polymer pairs, which may limit the applicability of these tribosystems. For PA6, the severity of surface damage as a function of the environment increased from dry to distilled water and sea water condition, as this material is susceptible to attack by polar solutions, which degrades its mechanical properties.

Solar pv system with pulsating heat pipe cooling

&lt;span&gt;Malaysia is blessed with high irradiance, making it suitable for solar photovoltaic installation for electricity generation. However, due to the broad wavelength of the solar irradiance, not all wavelength can be converted to electricity due to the limitation of the materials used for the photovoltaic. The infrared radiation absorbed produces heat, and coupled with high surrounding temperature, increases the temperature of the photovoltaic panel thus decreasing it efficiency. This paper presents the study of the effect of attaching pulsating heat pipe at the back of solar panel as a means of passive cooling. Pulsating heat pipe is a recent discovery in the heat pipe industry, introduced in 1996 by Akachi but has not been used for the purpose of cooling solar panels. This study shows the maximum difference between 5 Celsius between the pulsating heat pipe cooled panel and the reference panel without any cooling, resulting in 0.77% increase in electrical output efficiency&lt;/span&gt;&lt;span&gt;Malaysia is blessed with high irradiance, making it suitable for solar photovoltaic installation for electricity generation. However, due to the broad wavelength of the solar irradiance, not all wavelength can be converted to electricity due to the limitation of the materials used for the photovoltaic. The infrared radiation absorbed produces heat, and coupled with high surrounding temperature, increases the temperature of the photovoltaic panel thus decreasing it efficiency. This paper presents the study of the effect of attaching pulsating heat pipe at the back of solar panel as a means of passive cooling. Pulsating heat pipe is a recent discovery in the heat pipe industry, introduced in 1996 by Akachi but has not been used for the purpose of cooling solar panels. This study shows the maximum difference between 5 Celsius between the pulsating heat pipe cooled panel and the reference panel without any cooling, resulting in 0.77% increase in electrical output efficiency.&lt;/span&gt;

Effect of Deoxidation on Low-Alloy Steel Nonmetallic Inclusion Composition

Results are provided for an experimental study of the effect of deoxidation on the composition of nonmetallic inclusions in pipe steels melted in a vacuum induction furnace with a periclase lining. Thermodynamic calculations are made for oxygen activity within melts with lanthanum, cerium, aluminum, and yttrium for the metal of four melts. Conditions are evaluated for magnesium spinel inclusion formation in relation to deoxidant used and the extent of deoxidation. The effect is demonstrated of reduced aluminum concentration during metal ladle treatment on nonmetallic inclusion composition and the possibility of modifying them in the course of an industrial pipe steel melt.

Design and performance evaluation of a substitution solution for spiral casing of pico-hydroelectric plants

A test bench for Kaplan and Francis pico-turbines was developed at the University of Applied Sciences of Fribourg (Switzerland) to test different axial turbine designs from 0.3 to 6 kW. Using the experimental results, this test bench allows comparing the results of the CFD simulations and of the measurements of the tested turbines. During the test rig design, due to the different specific components of the axial turbine, a new concept was developed to replace the spiral casing. The current paper presents the new design of a substitution solution for the spiral casing of pico-hydroelectric plants and its performance compared to the standard solution by numerical simulations. The new concept, called “water-box”, had to fulfil some criteria: allow adapting to different geometrical dimensions (turbine diameters from 100 to 250 mm) as well as to different flow conditions (flow rate of up to 0.065 m3/s and to a pressure range up to 10 bar), while ensuring the same uniform flow distribution as with a standard spiral casing. In the same time, it had to allow optimizing other parameters like the space needed and the costs. The idea is to keep the principle of a sideway inlet and an axial outlet but using standard elements of industrial piping to reduce the costs. With this geometry, the fluid is naturally rotated and pushed towards the axial exit. There, a convergent pipe is mounted and finally, a stabilization grid which homogenizes the flow and break the rotation before the turbine. The performances of the new concept were evaluated and the results compared with a “standard” designed spiral casing by CFD simulations. The results showed that with the “water-box”, the pressure losses are 22 times higher. Nevertheless, the manufacturing simplicity of the water-box compared to the spiral casing achieves a substantial costs reduction of about 65 %. Thus, all the criteria were fulfilled. This simplicity associated with performances, which remain very interesting open new fields of application notably for pico-hydroelectric turbines installed for example on domestic sites.

Motion Control Analysis of a Spherical Robot as a Surveillance Robot

A robot is designed to be a helping tool for the human to work in the dirty, dull and dangerous environment, such as underwater, underground and disaster area. The most suitable type of robot for surveillance is a spherical robot. This type of robot has the ball-shaped, therefore minimize the contact to the ground, reduce friction, and energy consumption. All the components are shielded inside a shell; therefore it is possible to make this robot to be waterproof. One of the applications of this spherical robot is an industrial piping surveillance robot. The robot considered in this study is semi-autonomous where a user moves the robot through user interface installed in an android. The user can control the robot by examining the monitor. The input analysis of how the signal can move the robot is discussed in this paper. To prove the effectiveness of the proposed method, the robot is moved in an experimental setting including a pipe-like tunnel to test it. The robot moved and controlled smoothly, and it can maintain the position of the camera (robot head) always up to ensure the clear vision for the user.

Features of the current state of development of pipeline enterprises containing the "Ukrtruboprom" association

Purpose. Analysis of the development of metallurgical pipe enterprises of Ukraine, which are under the auspices of the association "Ukrtruboprom" at the beginning of 2019. A clear demonstration of trends in the development of the metallurgical industry in our country. Justification of proposals for a set of measures to overcome the negative trends in the pipe industry of Ukraine. The technique. When writing the article, a comparative analysis method was used to substantiate recommendations for overcoming negative phenomena in the pipe industry in Ukraine. Results. The article shows the dynamics of the development of the pipe industry in the country over the past year, with an emphasis on the domestic market. Recommendations for overcoming the negative trend of development of metallurgical enterprises, which are under the auspices of the association "Ukrtruboprom", in particular in the domestic market, are presented. The importance of introducing an automatic value added tax reimbursement system for exporting enterprises, as well as increasing the level of wages at pipe enterprises in Ukraine, was emphasized. Scientific novelty. The importance of the practical application of methods of control theory, in particular, the method of comparative analysis, was confirmed. This made it possible to formulate a series of step-by-step measures aimed at a comprehensive solution to the problems existing in the domestic pipe industry in Ukraine. Practical value. The information presented in this article will be of interest to a wide range of researchers and practitioners who are interested in the general trend of the development of pipe enterprises in Ukraine. Understanding the depth of the problems of domestic consumption of metal products in modern Ukraine is the first step towards solving them in the future. Keywords: association of enterprises "Ukrtruboprom", pipe production, management, development, internal and external markets for products

Assessing Materials’ Short-term Effectiveness on Controlling Zebra Mussel (Dreissena polymorpha) Attachment

Zebra mussels, an aquatic invasive species, cost millions of dollars each year to control due to their extensive attachment on essential industrial structures and detrimental effects on the native ecosystem. Reducing mussel attachment would allow researchers to control what surfaces these mussels attach to, and this reduction would prevent dangerous situations in industrial piping that occur when mussels prevent water flow. The goal of this research was to identify nontoxic materials that were effective in preventing or reducing the strength of zebra mussel attachment. We tested two materials, Sharklet and Netminder, that were designed to prevent biofouling of aquatic organisms, as well as two control materials, PVC pipes and a lake rock. The first experiment determined that Sharklet cannot prevent adult mussel attachment, but there was a statistically significant difference in attachment strength between Sharklet, the uncovered PVC pipe, and the rock. The second experiment determined that Netminder likewise cannot prevent adult mussel attachment and does not have a statistically significant difference in attachment strength with an uncoated PVC pipe. Since the Sharklet demonstrated some ability to deter mussel attachment, the material, along with other micro-engineered surfaces, warrant further study. Netminder likewise requires future study to determine its effect on zebra mussel veligers in a natural environment.

Comparison of NMR and microwave NDE methods for defect detection in composite structures

Abstract New advanced non-destructive evaluation (NDE) methods such as nuclear magnetic resonance (NMR) imaging and microwave NDE methods are being developed for their advantages and high resolution for defect detection in composite structures. Glass/epoxy composite structures are being used for many applications in industry. Often, glass/epoxy composite structures are used along with rubber lining in oil and gas pipe industry. Rubber is adhesively bonded to composite inner surface to meet the requirements. The interface of glass/epoxy composite and rubber lining is critical. Any de-bond (separation of adhesively bonded liner from composite surface) at the interface may lead to failure of composite structure due to corrosive gases and liquids. The present paper reports application of proton single sided NMR method to evaluate the de-bonds of rubber liner with composite. Results are compared with microwave NDE technique which is an advanced non-contact inspection method. Results indicate application of both these techniques for evaluation of bonded interfaces. Advantages of both the techniques over conventional techniques have been discussed. De-bonds within rubber lining were also detected and correlated.

Informal Institutions in Сontracting under Сonditions of Fundamental Changes (Evidence from the Large-diameter Pipe Industry)

«Вестник Санкт-Петербургского университета. Экономика» — научно-теоретический рецензируемый журнал, обобщающий результаты исследований ученых всего мира в различных областях науки, включая мировую экономику, историю развития экономики и экономической мысли, финансы, кредит и страхование, теорию и практику управления, статистику и учет, экономико-математическое моделирование.

Quality Assessment of High Density Polyethylene Pipe in Department of Water Supply and Sewerage

Before fiscal year 068/69, quality of procured pipes was not assessed in Department of Water Supply and Sewerage. Those High Density Polyethylene Pipes might not conform to quality standards and might have been reducing project life. Overall objective of this research was to analyze the quality of HDPE pipe based on laboratory test. All 21 set of test specimen result from different manufacturers have been analyzed’. The collected data were compared to the standards provided by Nepal Bureau of Standards and Metrology, which is NS 402042. This study was based on both qualitative and quantitative information gathered from visual and laboratory tests. NS 40 was published in 1983 and modified in 1985. Since then it is the document that governs Nepalese High Density Polyethylene Pipe industries. HDPE pipes produced from PE 100 are 47.97 percent lighter than PE 63. So, it should be adopted by Nepal Bureau of Standards and Metrology. PE 100 is only 5.27 percent more expensive than PE 63, so department should initiate to reduce the price of High Density Polyethylene Pipe. 2 and 2.5 kg pressure rated pipe are obsolete in procurement. As per the laboratory tests, it was found that Nepalese High Density Polyethylene Pipes met the quality standards. From the test analysis, it was also found that manufacturers intentionally lowered the weight than average and remained in the lower range to avoid failure in the laboratory test. Test certificates as per NS 40 should be mandatory in the frequency set by Nepal Bureau of Standards and Metrology. Office chief and Engineer should be assigned for quality assurance. Length and weight both should be considered in procurement process. Regional laboratory for High Density Polyethylene Pipe testing should be established by DWSS. Transportation cost of High Density Polyethylene Pipe should be based on analysis of transportation from truck up to the nearest road head. High Density Polyethylene Pipe fittings should be purchased based on the detailed drawing of pipeline network and actual need basis.

Strategic Analysis using TIROCA Model: Case Study at PT Steel Pipe Industry of Indonesia, Tbk. (PT SPINDO, Tbk.).

This paper aims to examine the application of strategic analysis with the TIROCA (Tangible Asset, Intangible Asset, and Organisational Capability) model as a basis to identify the strengths and weaknesses of a company, namely, PT Steel Pipe Industry of Indonesia, Tbk. (PT SPINDO, Tbk.). The company is one of the steel pipe manufacturers in Indonesia. The company has the largest production capacity in Indonesia and has experience in producing various kinds of steel pipes / tubes and various other related products. The company is one of the largest steel pipe manufacturers with the largets production capacity in Indonesia. The paper used a case study research method in order to explore the strategic strengths and weaknesses of the company through its: tangible asset, intangible asset, and organisational capability. The results of the study show the company's superiority come from the following three-resources: (1) tangible resources are derived from the sophistication of machinery and factory equipment; (2) intangible resources are generated from the innovation and creativity of the firm’s HR in creating various products; and (3) organizational capability resources derived from the firm’s competencies and skills in managing product development and the ability to recruit HR. Keywords: TIROCA Model, strategic analysis, tangible assets, intangible assets, and organizational capability

Pipe industry today and tomorrow (as per results of the XXIII-rd International scientific and practical conference “Pipes-2018”)

On September 17–19, 2018, the XXIII International scientific and practical conference “Pipes-2018” took place. 305 administrators and specialists from 123 organizations – developers, manufacturers and consumers of pipe products, as well as manufacturers of modern technological, testing and diagnostic equipment, including 15 representatives of foreign countries, took part in the conference. At the plenary session 13 actual reports were delivered, which became a basis of further well-reasoned dialog of scientific organizations with pipes manufacturers and biggest consumers. In the report of PAO “Gasprom” Head of Department Mr. P.V. Krylov “Technical development of Russian pipe companies for solving tasks of PAO “Gasprom” an information was quoted about application of domestic pipe products in Russian and international projects.Director of NO FRTP Mr. I.A. Malyshev acquainted the conference participants with pipes consumption dynamics in Russia by main market segments and possibilities of its growth. Items of industry’s science role increase in creation and mastering of new innovation kinds of pipe products were highlighted. Also measures undertaken by FRTP to protect EAES market against improper competition and items of improving instruments for the market protection In the report of the First Deputy-Chairman of RSPP Committee for technical regulation, standardization and correspondence estimation Mr. A.N. Lotsmanov items of the RSPP Committee participation in the work of import substitution and international cooperation. A special section was devoted to modern requirements in the standardization area and correspondence confirmation.At four theme sections 65 main reports were presented. Problems of innovation technologies and equipment for pipe steel production, billets quality for coil and sheet products were discussed. Items of protection against corrosion and increase of operational reliability, development and application of modern test and diagnostic equipment were also discussed.

An Apparatus for Measuring Heat Transfer Rate and Thermal Conductivity of Tubes جهاز لقیاس معدل الانتقال الحرارى والتوصیلیة الحراریة للمواسیر

الملخصان معدل انتقال الحرارة والتوصيلية الحرارية هما من أکثر الخصائصالمباشرة والعملية لتقييم أداء المواد لنقل الحرارة ولا توجد طريقة واحدة يمکناعتمادها لقياس الخواص الحرارية للمواد ولکن تقتصر کل طريقة قياس لتحديدالتوصيلية الحرارية على نطاق محدد من قيم التوصيلية الحرارية ودرجاتالحرارة وأنواع معينة من المواد ولا يتم تطبيق طرق قياس التوصيلية الحراريةعلى عينات عشوائية ولکن لکل طريقة يلزم وجود عينة قياسية لها بتصميموأبعاد محددة ومثال على ذلک يتم استخدام عينة دائرية بقطر نصف بوصةمغطاة بطبقة من الجرافيت لتکون معتمة تماما في طريقة القياس من نوعيةFlash Laser . ولکن في طريقة Guarded Hot Plate يتم استخدام لوح علىشکل متوازى مستطيلات ذو دقة تصنيع عالية و بأبعاد محددة.بالإضافة إلى القيود السابقة ، تتطلب بعض التجارب معادلات رياضيةخاصة بالإضافة إلى معرفة تامة بالخواص الفيزيائية للمواد وقاعدة معلوماتتتطلب فى بعض الطرق جهاز حاسوب وتناقش هذه الورقة تحديد معدل نقلالحرارة والتوصيلية الحرارية للمواسير فى صورتها التجارية باستخدام جهازبسيط جديد يستخدم معادلة فورييرللاشکال الاسطوانية فى الاتجاه القطرىلتعيين التوصيلية الحرارية للمواسيروتم فى هذه الدراسة قياس معدل التدفق الحرارى عبر عينات مواسير منالکربون استيل ثم تحديد التوصيلية الحرارية لهذه العينات وکانت القيم التى تمقياسها مقاربة لتلک الموجودة بالمراجع المعتمدة والموصفة لهذه المواد فعلىسبيل المثال تم تعيين التوصيلية الحرارية لعينة من الکربون استيل SA 53 Bبقطر داخلى 39.5 مم وقطر خارجى 44.5 مم وبطول 38.5 مم وکانت قيمةالتوصيلية الحرارية 15,2 وات /متر.کلفن بحيود - 5% عن القيمة المذکورةبالمرجع الأمريکى ) American Power Research Institute EPRI ( وهى16 وات /متر.کلفن. وتم أيضا قياس التغير فى معدل التدفق الحرارى لعيناتمواسير عليها رواسب وکان الفارق فى معدل التدفق الحرارى للعينات قبل وبعدالتنظيف واضحا باستخدام الجهاز حيث کانت الزيادة فى معدل التدفق الحرارىبعد التنظيف حوالى 0,8 وات مما يعنى أن الجهاز له حساسية وأدائية عاليةتسمح بالمقارنة بين عينات المواسير للحصول على أعلى المراجل کفاءةAbstract-The heat transfer rate and thermal conductivity are the most direct and realistic properties for evaluating the performance of materials to transfer heat. Each measuring method for determining the thermal conductivity is limited for specific range of thermal conductivities, temperatures and specific types of materials. Thermal conductivity measuring methods are applied to standard samples. Those samples are supplied in a specific design with defined dimensions i.e. are not similar to the forms used in the industry. For example, a circular specimen of half inch finished with a layer of graphite to be completely opaque is used in the Flash Laser Method. But in Guarded Hot Plate method a highly precision plate with definite dimensions is used.In addition to previous limits, some experiments require certain mathematical equations as well as advanced knowledge of physical properties of materials. This paper discusses the determination of heat transfer rate and thermal conductivity of industrial pipes in its commercial configuration using a new simple apparatus which uses the known Fourier equation for radial direction heat transfer in cylindrical pipe.In this study, the rate of heat transfer was measured for samples of carbon steel tubes and then the thermal conductivity of these samples was determined. The values measured weresimilar to those found in the approved and standard referencesFor these materials, for example, the thermal conductivity of a sample of carbon SA 53B was determined with an internal diameter of 39.5 mm and an outer diameter of 44.5 mm and a length of 38.5 mm. The thermal conductivity value was 15.2 W / m2. It was 5% - the value indicated by the American reference Power Research Institute EPRI (16 W / m(.in addition to that the difference between the heat transfer rate of three samples before and after cleaning were studied, the difference was about 0.8 Watt which means that the device has high sensitivity and performance.

Detection of scales and its thickness determination in industrial pipes using Compton backscattering system.

The ability to detect and quantify scales in pipes has been an important yardstick for efficient transfer of fluids in domestic as well as in application related industries. Knowledge of different kinds of scales formed has become a precondition for trouble-shooting in operational lines. In this paper, collimated Compton backscattered gamma rays from a radioactive source have been used to inspect the scales by automatic scanning in steps along the axial direction of different pipes. The methodology has been extended for the quantification of scales that prevails in the real functionality of extensive usage of fluids. To aid for descaling processes, the desideratum is the density determination of scales and this parameter is quantified non-destructively and is also validated with the standard density. The described non-intrusive gamma ray densitometry is quite promising, efficient and has highly reliable results for scale detection with the squared correlation coefficient of 0.98. The proposed technique shows a better linearity than the gammatography technique.

Test of measurement device for the estimation of leakage flow rate in pneumatic pipeline systems

Background: Indirect measurements of flow rate serve to determine air consumption, leakage values and characteristics of compressed air systems (CASs). Method: A new method of indirect flow rate measurement in a pneumatic pipeline system was developed. The method enables to measure the controlled leakage in a branch line and was used to construct automatic measuring systems auditing the compressed air systems piping. Results: First, the leak-testing instrument LT-I 200 was designed, constructed, and tested as portable measurement device for the estimation of air leakage flow rate in pneumatic pipeline system. Next, based on the authors’ patent, the automatic measuring system for the measurement of the leakage flow rate in industrial compressed air piping was developed. Conclusion: The measurement device was used to estimate of the leakage flow rate and cost of the energy losses in the compressed air piping system.

Multi-parameter dynamical measuring system using fibre Bragg grating sensors for industrial hydraulic piping

Due to the risk of failure induced by vibration fatigue, performance testing and condition monitoring are important to hydraulic piping systems in some critical industries such as nuclear power, oil and gas, and aerospace. A multi-parameter dynamical measuring system using Fibre Bragg Grating (FBG) sensors is proposed to detect multiple physical parameters (strain, temperature, pressure, acceleration, etc.) in industrial hydraulic piping. This paper investigates the multi-parameter measuring principle of FBG and presents the framework of the proposed system. Multi-parameter dynamical measuring experiments on a hydraulic piping test platform were carried out to validate the system. Multiple parameters of the hydraulic piping were obtained and analysed in the time, frequency and modal domains. The results obtained by FBG sensors are in good agreement with those detected by the reference electrical and piezoelectric sensors. The proposed system was implemented to monitor the clamping looseness of the pipe. Experimental results indicate that the proposed system could be used for multi-parameter dynamical measurements and real-time condition monitoring of complex industrial hydraulic piping systems in harsh environments.

Elastic Response of Acoustic Coating on Fluid-Loaded Rib-Stiffened Cylindrical Shells

Reinforced cylindrical shells are used in numerous industries; common examples include undersea vehicles, aircraft, and industrial piping. Current models typically incorporate approximation theories to determine shell behavior, which are limited by both thickness and frequency. In addition, many applications feature coatings on the shell interior or exterior that normally have thicknesses which must also be considered. To increase the fidelity of such systems, this work develops an analytic model of an elastic cylindrical shell featuring periodically spaced ring stiffeners with a coating applied to the outer surface. There is an external fluid environment. Beginning with the equations of elasticity for a solid, spatial-domain displacement field solutions are developed incorporating unknown wave propagation coefficients. These fields are used to determine stresses at the boundaries of the shell and coating, which are then coupled with stresses from the stiffeners and fluid. The stress boundary conditions contain double-index infinite summations, which are decoupled, truncated, and recombined into a global matrix equation. The solution to this global equation results in the displacement responses of the system as well as the exterior scattered pressure field. An incident acoustic wave excitation is considered. Thin-shell reference models are used for validation, and the predicted system response to an example simulation is examined. It is shown that the reinforcing ribs and coating add significant complexity to the overall cylindrical shell model; however, the proposed approach enables the study of structural and acoustic responses of the coupled system.

PENGARUH KOMPENSASI NON FINANSIAL, MOTIVASI DAN KEPUASAN KERJA TERHADAP KINERJA KARYAWAN

The purpose of this research is to explain the influence of nonfinancial compensation, motivation and job satisfaction on employee performance of PT Bakrie Pipe Industries Bekasi partially and simultaneously. The research this use quantitative approach by using interview and questionnaire. The samples using purposive sampling technique with Slovin formula resulted 217 respondent samples. Data analysis used validity test, reliability test, multiple linear regression test. The result of the research found that: (1) Nonfinancial compensation has no significant effect on employee performance; (2) Motivation have significant effect on employee performance; (3) Job satisfaction have significant effect on employee performance; and (4) Nonfinancial compensation, motivation, and job satisfaction have significant effect on employee performance.&#x0D; Keywords: Nonfinancial Compensation, Motivation, Job Satisfaction, Employee Performance

Carburization level identification in industrial HP pipes using ultrasonic evaluation and machine learning

Ultrasound nondestructive testing is commonly applied in industry to guarantee structural integrity. HP steel pyrolysis furnaces are used in petrochemical industry for lightweight hydrocarbon production. HP steel chromium content may be reduced in high-temperatures due to carbon diffusion. This characterizes the carburization phenomenon, which modifies magnetic properties, reduces mechanical resistance and may lead to structural rupture. For safe operation it is required to frequently determine carburizing level in pyrolysis furnace pipes. This is traditionally performed manually using magnetic evaluation. This work proposes a novel procedure for carburizing level estimation using ultrasonic evaluation associated to signal processing and machine learning techniques. Experimental data from pulse-echo ultrasonic tests performed in HP steel pipes are used. Discrete Fourier transform was applied for feature extraction and different classification systems (neural networks, k-nearest neighbors and decision trees) are applied and compared in terms of carburizing level identification efficiency.