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The article deals with the method of calculating pressure on the outer surface of the casing at the device of bore drilling wells on the basis of the results obtained during the experiments carried out in laboratory conditions. The purpose of the work is to reduce the material capacity and, consequently, to reduce the cost of foundations made with the use of bored piles.

The paper considers the methodology for determining the critical angle to the horizon when the borehole walls in the bases, composed of underconsolidated sandy soils collapse. The purpose of the paper is to develop a criterion by which ground collapse occurs in a borehole. The paper considers the determination of geometric form parameters of the soil that lost stability and weight. The proposed mathematical modeling of the collapse form shows that the stability of the borehole walls depends not only on the angle of internal friction of the soil, but also on its specific weight and the diameter of the borehole itself. The geometric form of the borehole collapse and its weight obtained in the process of modeling will allow to determine the crimping pressure acting on the outer surface of the casing under the protection of which the drilling is carried out in under consolidated sandy bases in the next stages of research. Knowing the amount of pressure compressing the casing pipe, we can calculate it by the material and the optimal wall thickness. It is possible to calculate the cross-section of the pipe for geometric invariance. It is able to calculate the cross-section of the pipe for geometric invariance. Calculation of the casing pipe material will allow the implementation of modern, light and durable materials in the construction, which significantly reduce the cost of construction of zero cycle structures. The geometric invariance of the casing pipe cross section is an important condition responsible for the geometric dimensions of the future pile in the project documentation. It should also be noted that according to the results of preliminary calculations on the proposed mathematical model, it was found that the sand base cannot have a verticality of 90-degree slope. Drilling of boreholes in the described soils cannot be carried out without the use of casing.

The formation of cracks in the cement sheath and delamination at the cement to steel casing interface due to shrinkage compromises the overall structural stability, imperviousness and durability of oil wells. Particularly, the flow of downhole fluids (e.g. methane or oil) through the cement sheath has become an environmental issue both in offshore and onshore oil wells. This study investigates the impact of fibre reinforcement on the initiation and propagation of cracks in a simulated oil-well section. The study combines a modified setup based on the ASTM-C1581 ring-test with Digital Image Correlation (DIC) in order capture, quantify and measure the initiation and propagation of cracks in the hardening cement and characterize the cracking pattern observed due to autogenous and drying shrinkage deformations and resulting self-induced stresses in the section. The experimental results obtained show the beneficial effect of fibre reinforcement on reducing the extent of cracking by increasing the post-crack ductility of the hardening cement. However, fibre reinforcement had a negligible role in preventing cracking initiation, which is governed by the cement matrix and degree of restraint. This study highlights the benefits of fibre reinforcement as a mitigation measure to reduce shrinkage-induced damage in oil-well cements.

The paper proposes a module for automatic punctuation prediction and casing reconstruction based on transformers architectures (BERT/T5) that constitutes the current state-of-the-art in many similar NLP tasks. The main motivation for our work was to increase the readability of the ASR output. The ASR output is usually in the form of a continuous stream of text, without punctuation marks and with all words in lowercase. The resulting punctuation and casing reconstruction module is evaluated on both the written text and the actual ASR output in three languages (English, Czech and Slovak).

The oil and gas industry uses drilling, casing, and compressor pipes connected by threaded couplings. Variable tensile forces load a drill string during its operation in a well. Experience shows that pipes are destructed on the body of the pipe or in the thread’s roots. It indicates the importance of studying the contact stresses in the elements of threaded joints. To theoretically determine the distribution of contact stresses in a “pipe - coupling – pipe” thread joint, an integral equation is drawn up with the thread joint’s contact pressure as an unknown variable. To develop this equation, it is necessary to determine the radial displacements and angles of rotation of the normal in the coupling and pipes caused by a single annular force or a single annular moment applied in any normal cross-section. Based on the theory of thin shells of finite length, a method for determining the radial displacements of shell middle surface points (coupling), due to the annular force applied in its arbitrary cross-section, as well as the angles of rotation of the normal to its middle surface caused by these force factors. The fact that the annular moments in the right and left parts of the coupling are opposite has been considered.

In the present work, the influence of different printing parameters (number of perimeters, flow, extrusion temperature, layer height and printing speed) on the watertightness of 3D printed parts has been studied. The vessels have been printed on polyethylene terephthalate glycol (PETG) by fused filament deposition modeling (FDM). A total of 27 prismatic vessels have been manufactured, following a fractioned experimental design. By means of a simple test, the quantity of water that has leaked from each vessel after seven hours has been measured. After analyzing the results obtained, using Taguchi method and analysis of variance (ANOVA), it can be stated that the number of perimeters and the flow are the most influential parameters in the watertightness of the vessels. One of the vessels tested had zero leakage. With the printing parameters of this vessel, an housing has been printed for an ARDUINO board. The watertightness of the housing has been tested by immersion at a depth of 1 m for 30 min, according to the UNE-EN 60529:2018 standard. Although it did not pass the test, the quantity of water that entered the casing was less than 0.5 g.

The technology of aluminum electrolysis is permanently improved in the direction of increasing the unit power of electrolyzers. The leading aluminum companies over the world try to exploit powerful electrolyzers with roasted anodes operating at current intensities higher than 300 kA because their application improves the ecological and economic efficiency of new plants. The elevation of the current strength aimed at increasing the productivity of electrolyzers is often restricted by the negative consequences of thermal load influence. To get a stable technology of electrolysis when the power is increased, it is necessary to guarantee the possibility of efficient heat removal from the structural elements. We present the materials on the development and verification of the mathematical model of electrolyzers with a base level of current strength equal to 300 kA. The power parameters of electrolyzers are obtained for the current strength elevated up to 330 kA.

The 3d printing technology and 3D designing are the important inevitable skills that are to be learnt to satisfy the industrial and household requirement. More software to create and animate designs are presently available that include CATIA, Freecad, Pro-E Solid works, etc. This chapter mainly focuses on the designing basic part design and part assembly for creating IoT prototypes and necessary casing to mount sensors and breakout boards. CATIA-based design examples are discussed along with the importance of 3D printing in this chapter.

In shale gas reservoir, casing eccentricity often occurs during casing cementing. In addition, the fracturing times are more and the downhole temperature field changes greatly during later reservoir reconstruction. Therefore, this paper establishes casing eccentric thermal-mechanical coupling model, determines the change law of temperature field at the heel end of casing and that of instantaneous stress of casing with time, and analyzes the effects of injection temperature, internal pressure, displacement and elastic modulus of cement sheath on the instantaneous stress of casing. Results indicate that the casing temperature decreases rapidly to nearly constant temperature during fracturing. The maximum stress of inner wall of casing increases with the increase of eccentricity angle. In the thermal-mechanical coupling simulation, the maximum stress of the casing first stabilizes briefly with time, then decreases sharply, and finally stabilizes at a constant temperature. The heat transfer coefficient increases with the increase of displacement, and then the maximum stress of casing also increases. The results can be used as reference for the analysis of influencing factors of casing damage during the fracturing of horizontal shale gas Wells.

The method of studying the elastic and strength properties of cementing materials used in the construction of wells in the fields of the Khanty-Mansiysk Autonomous Okrug is considered. The studies were carried out at different times of hardening of cement stone and under the influence of clay acid reagent on the example of two compositions CGES-W and PCG-I-G-SR-1. The experimental results showed for both types of cements an increase in the tensile strength and elastic modulus, and decrease in the Poisson's ratio during hardening. It is shown that the effect of clay acid reagent has a negative effect on the strength characteristics of cement stone, which increases with increasing time period of clay acid processing. In conclusion, the analytical functions are obtained that most closely describe the changes in the elastic-strength properties of the studied types of cements, both over time hardening and depending on the time of exposure to the clay acid reagent. The obtained analytical functions can be used in the future to numerically simulate the stress–strain state of the near-wellbore zone and determine the conditions for the destruction of the well support during hardening and under the influence of clay-acid treatment.

Modern tools with interchangeable cutting inserts currently have a significant impact on the cost of production. A wide variety of tools from the world's leading manufacturers and the binding of the tool casing to the manufacturer of the cutting inserts leads to large stock storage of the same type tools from different manufacturers at the enterprise. There is a division at the enterprise capable to make independently the case of the tool for any cutting inserts, but it is necessary to design the case of the tool for this purpose. This article discusses the design of end mill casings based on the parametric model in the SOLIDWORKS system. The parametric technology allows for a quick design of the end mill case based on the created prototype. As a result, it is possible in a short time to develop and manufacture the end mill case for various types of processing, which will lead to a positive economic effect for the enterprise.

The present work deals with experimental measurements of rotordynamic force coefficients for two types of impellers: open (unshrouded) and closed (front shrouded). The impellers were designed to work in a turbopump with a cryogenic fluid, but experiments were performed in a test rig where water is used as working fluid. All the tests were conducted with a vaned diffuser. For both configurations, the supply pressure is 0.6 MPa, knowing that the whole test rig is pressurized at 0.5 MPa. The rotor is centered and the operating rotating speeds are 2000, 3000, and 5000 rpm. For each rotor speed, according to a double conical hydrostatic thrust bearing and eight piezo electric actuators, dynamic displacements in two different directions are applied to the rotating impeller, within a frequency range from 20 to 110 Hz. The resulting displacements and forces are measured in order to identify rotordynamic force coefficients using complex impedances. Stiffness and damping coefficients are compared and discussed in order to highlight the influence of the shroud together with the eye-packing seal and front casing on the impellers performance.

A recent development in the field of seismic resistant structures is the buckling‐restrained brace (BRB) which is a passive hysterics damper. Its uniform hysteric performance is achieved via a composite structure. Concrete is encased around a yielding geometry to control its buckling. A steel member is used as a core, concrete as casing material, and a stiff connector to incorporate this deceptive device in-between frames. The symmetric response of the core under tension and compression is achieved by restraining the core under critical buckling load. Due to its relatively simple design methodology and working BRBs are used in new as well as old structures as a retrofit. This paper reports the modeling and design procedure of BRBs along with their development since its first application. The design methodology and procedure for mathematical modeling of BRB are described in detail. The paper is a state of the art review based on the recent developments in BRBs and their application in structures. A focus on gap analysis underlining the loopholes and further requirements is addressed and are presented in the form of conclusions so that the future scope for the researchers can be underlined.

This study represents the research dependency of uniform stress distribution degree in an elastic isotropic deformable body (elastic half-plane and elastic monolithic thick cylinder) from the distance between the rectangular elements which have contact with the deformable body considered in the two-dimensional formulation. The nature of contact interaction with deformable rectangular elements presented as unidirectional exposure on the deformable body of rigid either elastic rectangular stamps, as well as exposure to uniform pressure simulating contact pressure in the line of contact interaction. The mathematical model is obtained for calculating stresses in an elastic half-plane loaded with uniform constant pressure in two sections of finite length in the two-dimensional formulation (development of an analytical solution to the Michel task). A method for assessing the relative uniformity of the stress distribution in an elastic isotropic deformable body is proposed. This method is based on discrete control of the absolute values of the target stress components on finite element models (FEM). The results of a numerical study of the stress state of objects emulating the inner casing of the insulating layer (Pimshtein et al. in Autoclave for the synthesis and growth of crystals in hydrothermal conditions, 1997; Elovenko in Future directions of the development of high-pressure autoclaves. Herald Irkutsk State Tech Univ: 41 277–279, 2010] or a constructive element on which multilayer components of the bearing part of the vessel housing are mounted in contact with the distance planks (Elovenko et al. in Experimental study of the autoclave model for hydro-thermal synthesis of minerals. Baikal Lett DAAD 7:11–19, 2010) are presented by FEM. The effectiveness of the proposed numerical research method is confirmed by comparing the results of solving typical test problems with known analytical solutions.

Extreme downhole conditions often apply a high pressure on tubing or casing that poses a severe challenge to well integrity. Imperfections in these tubular elements are very prone to cause rupture under high pressures. The American Petroleum Institute (API) proposed a method to calculate the rupture pressure for the tubing or casing with radial cracks perpendicular to their inner surface. Stress analysis indicates that an inclined crack would propagate in mixed modes. This study presents an investigation on the stress intensity factor at an oblique fracture initiating from the inner surface of tubing based on finite element methods. The simulation shows that the shear mode would dominate the crack extension as the incline angle increases. Both stress intensity factors in traction and shear modes rise with the pressure inside the tubing. Thicker tubing would mitigate the stress intensity factor. A conservative criterion for crack propagation in mixed modes provides the minimum pressure under which the inclined crack would grow. This criterion also estimates a burst strength factor used for rupture pressure prediction. Results show that the burst strength factor increases firstly and then decreases with the incline angle. Its maximum value reaches 3.2 and occurs at about 20°, which is much higher than the default value by API. This work demonstrates the necessity of considering the crack propagation in mixed modes in rupture failure of tubing.

In this paper is analyzed turbulent swirling flow generated by axial fans. Three cases will be presented. The first one is the axial fan impeller in-built in the pipe 27.74D long, where D = 0.4 m is pipe inner diameter. The second case is study of the turbulent swirling flow in the free jet generated by the axial fan impeller with casing. The third case is conical diffuser with the inlet diameter D = 0.4 m and total divergence angle of 8.6°, studied in the test chamber followed by the flow meter. Axial fan, even in the case of the same impeller geometry, had various duty points in all these installations. All regimes were adjusted by the continuous fan rotation speed regulation, as well as with the impeller blade angles. Only in the case of the installation with diffuser, additional regulating valve and booster fan were sometimes applied. In all these cases was used laser Doppler anemometry (LDA), one- and three-component systems. All generated flows are extremely turbulent and in the case of the pipe and diffuser occur reverse flows in the central flow region. In the paper will be discussed calculated integral values, such as average circulation or swirl number. Time-averaged circumferential velocity profiles revealed Rankine vortex type in pipe, while in the diffuser is generated, with the different type of impeller, solid body profile. Turbulence levels and their distributions are analyzed. In addition, statistical moments of the higher order, like skewness and flatness factors are discussed.

Technological development has a high impact on the everyday life of humans and their working conditions. Noise generated by devices is an important problem in numerous environments. Such a problem is explored in this chapter. A classical protection solution is to apply passive sound insulating materials. However, passive barriers are often ineffective, especially at low frequencies. They may also be inapplicable due to technical reasons. An alternative way is to use active control methods. If a device generating noise is surrounded by a thin-walled casing, or if it can be enclosed in an additional casing, control inputs can be applied directly to the structure, and as a whole the casing can be used as an active barrier enhancing acoustic isolation of the device. If appropriately implemented, it results in a global noise reduction instead of local zones of quiet. The aim of the authors is to present the theoretical basis for developing active device casings. The chapter presents exemplary plants, discusses the principles of building a mathematical model and using it to build optimal noise reduction systems, passive, semi-active and active. Examples of results confirming the development of a new concept of global noise reduction for machines and devices are given.

Rotary kilns are industrial furnaces used for the continuous processing of raw materials at high temperature, consisting in long steel cylinders lined with refractory bricks and revolved by gears. They are subjected to complex stresses and deformations due to high temperatures and heavy loads, so monitoring and planned maintenance are essential to avoid very expensive unexpected shutdowns and other damages to the exterior shell. The interior of a rotary kiln has been acquired with a terrestrial laser scanner during a maintenance shutdown for checking the wear of the refractory brick lining. Up to now, the refractory lining of the surveyed plant was checked every year taking manual measurements, but this technique produced discontinuous data only. The 3D model has been unwrapped to show the deviation between the current state and the design drawings. The model showed the degradation of the refractories and the thickness of the incrustations in a continuous way on the whole surface. In addition, in this application laser scanning can be considered as a diagnostic imaging technique because degradation patterns can give some indications on the deformation of the steel casing. By selecting some reference points integral to rotating parts, instead to the motionless structures outside the furnace, a permanent reference system has been established to reliably repeat monitoring over time.

The mutually counteractive loads that develop inside power-recirculating planetary gearing as outlined in Chap. 3 represent one important example of the so-called subtle or obscure loads. However, there are other cases to be highlighted. A real-life case study is presented of the premature and unexpected failure due to the designer failing to anticipate the phenomenon of double-helical pinion shuttling, which—as such—is known to gearing design and operation experts. Another source of obscure load is the equalizing tilting-pad thrust bearings when operated under some angular misalignment; they do possess a so-called pivotal stiffness. Gyroscopic design engineers will not be mistaken about the sometimes substantial reactions on the bearings and the casing, but it is feared that such loads may be subtle or obscure to the mechanical design engineer when dealing with fast-spinning, high-angular-momentum machine parts. Essential calculations pertaining to wobbling machine parts are given.

With long-term operation of pumping and other equipment, there is often a need to extend the life and assess the residual life. Modern life-time assessment methods are based on three-dimensional modelling and the finite element method. Within the framework of these methods, geometric models are constructed that take into account the thinning of the walls of the pumps as a result of operation. By constructing geometric models, finite element models are constructed. These models are made taking into account the conditions of loading of the structure, tightening of bolted connections, technological and temperature loads. The constructed models allow to assess the strength of the pump casing and the main bolted connections during normal operation and gyro testing. The paper assesses the cyclic strength of these structural elements. The results of the work confirmed a sufficient residual life-time for safety pump operation in the next 15 years.

Planetary gearbox could provide considerable transmission ratio in a small casing. Usually, planetary stage works under heavy loads. Gears inside planetary gearbox may suffer from damages including pitting, spalling and tooth broken. Sun gear fault diagnosis is a challenge since sun gear is in the center of the planetary gearbox. To address fault diagnosis of sun gear, a method named continuous vibration separation is presented in this paper. The method is compared with MED, which is a impulsive signal enhancement method. Fault seeded experiment is conducted to validate the method. Signal analysis result indicates that a combination of CVS and MED is more effective.

Vane pumps have several applications in the automotive and aviation industries. Many factors affect pump performance. So, modifying the pump design plays an important role in pump performance and efficiency. Computational fluid dynamics (CFD) techniques became an adequate tool to design and optimize the pump as they can save time and cost. In this chapter, a parametric study for an unbalanced vane pump model will be shown, by studying the effect of two parameters which are the model vanes number and the gap height between the vane tip and the pump casing. A three-dimensional model was built and simulated using ANSYS (Fluent). The shear stress transport (SST) k – ω turbulence model was used in all simulations. Three different gap heights and three different vanes number models were simulated. The model with gap height of 0.1 mm gave the best flow rate and output power. Moreover, three models with four, six, and eight rotor vanes were modeled. The characteristic map was determined, and the eight-vane model gave the best output flow rate.

In permanent P&A, establishment of a rock-to-rock barrier is a requirement. There are situations where the annular barrier behind casing is not qualified or there is no annular barrier. Therefore, full access to the formation shall be obtained. Different techniques have been utilized by the petroleum industry such as cut-and-pull, casing milling, and section milling. Some new techniques have been suggested some of which are in use and others are in development. Such techniques include perforate-wash-cement, upward section milling, melting downhole completion, and plasma-based milling. This chapter will present these techniques, briefly.

In many boreholes, casing is used and cemented to seal the borehole wall and to stabilize the borehole. Figure 4.1 shows a schematic diagram of a cased hole. The annulus between the casing and formation may be filled with fluid or cement. Table 4.1 lists the geometrical and elastic parameters of a well-cemented cased hole model.

Axial and lateral loads of lightweight beam truss structures e.g. used in automotive engineering may lead to undesired structural vibration that can be reduced near a structural resonance frequency via resonant piezoelectric shunt-damping. In order to tune the electrical circuits to the desired structural resonance frequency within a model-based approach, an adequate mathematical model of the beam truss structure is required. Piezo-elastic truss supports with integrated piezoelectric stack transducers can transfer the axial and lateral forces and may be used for vibration attenuation of single beams or whole beam truss structures. For usage in a single beam test setup, the piezo-elastic support’s casing is clamped rigidly and is connected to the beam via a membrane-like spring element that allows for rotation as well as axial and lateral displacements of the beam. In this contribution, the piezo-elastic support is integrated into a two-dimensional beam truss structure comprising seven beams, where its casing is no longer clamped rigidly but is subject to axial, lateral and rotational displacements. Based on the previously verified and validated model of the single beam test setup, two different complex mathematical models of the piezo-elastic support integrated in the two-dimensional beam truss structure are derived in this contribution. The two mathematical models differ in their number of degrees of freedom for the piezo-elastic support as well as in the assumption of rigid or compliant casing. By comparing numerically and experimentally determined structural resonance frequencies and vibration amplitudes, the model that more adequately predicts the truss structure’s vibration behavior is selected on basis of the normalized root mean squared error. For future works, the more adequate model will be used to tune electrical circuits for resonant piezoelectric shunt-damping in a three-dimensional truss structure.

Absence of full-scale tests results on real models that adequately reflect the physical and thermodynamic processes occurring in the intertubular space during oil production does not permit to develop effective technological methods as well as organizational and technical measures for the prevention and reduction of the probability of hydrate formations, corrosion-active against the surface of casing, and tubing in the annular space of oil wells. To extend the lifetime of oil and gas facilities, the information-measuring system and equipment have been developed, which permit to fully approximate the conditions and modes of hydration of iron and its oxides to real down-hole processes and characteristics, which make it possible to investigate hydrate formations with a wide probability in a wide variation range of temperature and pressure. Obtained through information and measuring system, the results of the statistical experiments gave the opportunity to determine the conditions necessary for hydrate formations of iron (Fe) and its oxides in the temperature range from −15 to +60 °C and a pressure of 0–60 MPa, which confirmed thermodynamic calculations of phase equilibria in the annular space of wells known from the literature.

Aluminium Company of Greece operates with success its anode baking furnace since its start-up more than five decades ago. Thermal and mechanical stresses created by the baking process however affected the integrity of the concrete casing in the central part. Distortions, deformations and cracks were indeed visible in comparison to the outside part of the casing. This paper goes through the different phases undertaken by Aluminium Company of Greece in order to successfully develop and safely realize the replacement of the casing walls in the central passage as well as the anode conveyor supporting structure while limiting costs and impacts on production and anode inventory. The article details the technical challenges and innovative solutions as well as the project and operation organization put in place in order to realize the work without any safety incident and in a strict schedule of ninety days.

Indian ceramic production is 100 Million ton per year in the ceramic industry, about 15–30% waste is generated from the total production. Dumping of ceramic waste leads to serious environmental and dust pollution and occupy large area. To avoid these conditions, it is desirable to reduce the stockpiles of ceramic waste by recycling or other alternative methods. Stone columns are one of the versatile techniques for engineering the ground. It is the most effective solution for improving the strength of soil and thereby protecting against liquefaction with less installation time. Our aim is to investigate the feasibility of using ceramic waste as aggregates in stone columns there by reducing the waste disposal, to provide a replacement to aggregates in columns and to minimize the cost of soil stabilization. Method/analysis: Experimental study on the load settlement behavior (IS 1888–1982) in test model of Ceramic stone column, Ceramic stone columns with geotextile casing, Ceramic stone columns with horizontal arrangement of geotextile, Ceramic stone columns with both horizontal layering and casing of geotextile and to compare with the ordinary stone column. Result shows that improvement in the load carrying capacity is found less in ceramic as compared to stone column but by the introduction of geotextile casing and layering, found an increase in the load carrying capacity.

The chapter presents a brief description of the experimental unit made on the basis of a dynamic test bench and the results of bench tests of a single-support pneumatic suspension, including sprung and unsprung masses, pneumatic spring with a sleeve-type rubber-cord casing, air damper mounted in the piston of the air spring, receiver and hydraulic shock absorber. The chapter contains the following: elastic characteristics of air springs with different operating volumes, damping characteristics of the hydraulic shock absorber, oscillograms of free damped oscillations of the sprung mass of 0.5 t after the push of the suspension from the bottom up and down by 100 mm, amplitude-frequency characteristics of oscillations of the sprung and unsprung masses at a harmonic kinematic disturbance with an amplitude of 12 mm. The maximum temperature and the time of reaching the steady-state temperature of the various surfaces of the air spring are determined with the help of a permanently installed professional thermal imaging camera.

Accurate prediction of the annular pressure buildup in deepwater oil and gas well is of great significance for drilling and production of oil and gas. In order to predict the annular pressure buildup, casing annulus temperature distribution is calculated by considering the deep water well structure and wellbore heat transfer process. And the prediction model of annular pressure buildup is established. Newton down-hill method is used to solve the model. The reliability of the model is validated by comparing predicted results of the model with monitoring values in the oil field. The results indicate that the predicted results are in good agreement with monitoring values of casing annular temperature and pressure, and the max relative error is less than 10%. The accuracy can meet the needs of engineering. In addition, compared with the simple iterative method, computing speed of the Newton down-hill method is relatively faster. In words, the model can provide theoretical guidance for the accurate calculation of annular pressure buildup.

Carbon capture and sequestration (CCS) is one of the most promising technologies to mitigate greenhouse gas levels. To ensure an effective underground storage, well integrity is critical to isolating the injected fluid between different zones or back to the surface. Among the wellbore components, the cement sheath is the most important sealing element for zonal isolation. However, cement is vulnerable and prone to cracking that may provide leakage pathways for CO2. Both laboratory study and field test show that thermal stresses caused by the temperature variation in the wellbore are a major factor for the mechanical integrity loss of cement. This work focuses on the mechanical response of the casing-cement-formation section above the injection zone. We firstly propose a wellbore flow model to predict the temperature distribution along the well depth. Then we calculate the induced stress in cement during injection by a finite element simulation. To identify the cement failure mode, we introduce failure factors by the Mogi-Coulomb criterion, tensile strength and interfacial strength corresponding to shear compressive failure, radial cracking and debonding at the casing/cement or cement/formation interfaces, respectively. A parametric study is conducted to investigate the influence of the injection temperature and rate as well as casing eccentricity on failure factors. The results show that radical cracking and debonding at the cement/formation interface are the main failure modes during CO2 injection. Both the two failure factors would increase linearly as the injection temperature decreases while they grow non-linearly with the injection rate. In addition, the casing eccentricity exacerbates the risk of cement integrity loss by increasing failure factors. This study provides a failure assessment of CO2 geological sequestration and guidelines for injection operations.

In the ordinary plan practice, the structures are thought to be settled at their bases despite the fact that they are bolstered on adaptable media (soil) which will change the auxiliary conduct. Along these lines to assess the practical conduct of structure the dirt structure communication impact will be consolidated in the examination. In the present examination, two SSI models are considered for the analysis; first is supplanting soil by spring of equal firmness and second considering the entire soil mass underneath balance. It is conceivable to control these impacts by giving the tie pillar in the balance. The investigation is carried on 3D building casing of various story statures bolstered on delicate soil. The seismic investigation is done utilizing identical static strategy according to IS 1893–2002. The investigation uncovers that the SSI essentially modifies the powers/minutes in the individuals from the structure which is conceivable to control successfully by giving the lash balance.

An early detection of abnormality through partial discharge measurement is important for the maintenance of the power quality of equipment. Thus, our group has developed a diagnostic method measuring the ultrasonic waves associated with the partial discharge occurring in a metal casing. As a characteristic test of ultrasonic waves, the discharge current and the ultrasonic wave signal associated with the partial discharge were simultaneously measured. An analysis of each detected signal revealed that there is a possibility that the frequency components of the ultrasonic wave signal have a correlation with the partial discharge charge amount. Ultrasonic waves are elastic, thus the thermal expansion of the medium has an influence on the waveform. Therefore, it is considered a reasonable result that the frequency characteristics of the ultrasonic waves are associated with a partial discharge. Incidentally, it is necessary to estimate the partial discharge charge amount in the case of diagnosing insulation degradation. The partial discharge charge amount is usually determined by the signal strength. Thus, it is necessary to specify the location of the partial discharge occurrence, because the signal intensity of ultrasonic waves decreases with distance. However, by using the knowledge about the frequency characteristics obtained in this work, it becomes possible to estimate the partial discharge charge amount through the ultrasonic wave frequency, without specifying the partial discharge location. In order to evaluate the possibility of the application to actual equipment, our diagnosis method was tested on an oil filled equipment with insulation failure. The test was performed monthly over a three-month period. Each resulting estimated charge amount was less than 1000 pC. Further, a dissolved gas analysis was also carried out each time. The result indicated there was no noticeable change in the acetylene content. Acetylene is generated when a discharge of over 1000 pC occurs. From the above results, the transition value is considered as a reasonable result. In the future, we will try to determine the characteristics of an ultrasonic wave signal accompanying a partial discharge. We also plan to improve the accuracy of a partial discharge diagnostic method.

An experimental complex on a high pressure casing was developed for the research of vibrating processes of powder materials pressing. As a high pressure casing hydraulic hoses of high pressure pressed to the elliptic state were used. Hydraulic pump—a pulsator—is the upgraded gear pump in which a quarter of one tooth was cut. The modes of transition of a hydraulic motor through resonance were investigated. It is proposed to use the mode of fluctuation switching from coordinate X to Y and vice versa to create vibrating actuators of periodic action with a large vibration traction effort due to the massive energy storage. The developed experimental complex can be used both for one-sided and for dry isostatic pressing. The complex allows to implement spatial variations of the press-mould. The frequency and oscillation amplitude can be regulated. The frequency can be regulated by changing the turns of the hydromotor, and the amplitude—by changing the pressure values in the system. The method of calculating vibration modules on a high pressure casing is developed.

In this experimental work, possible solutions to the problem of damage to the impeller of the centrifugal (radial) fan are provided. Due to the impact of the impeller, a breakdown (damage) of the casing occurred, and then to the bending of the shaft of the fan assembly. In the first part of the paper, as a proposal of the solution, the reconstruction of the axle mounting on the basis of the installation of double bearings of the same type and the structural change of the blades of the rotor was done. In the second part, the process of reconstructing the impeller of the fan with modified production technology was worked out to solve the problem of balancing the mass. The study defines the methodology to be followed through the design documentation and the Instructions on the assembly process, which must be strictly observed. By complying with the prescribed technological procedure, the lifetime of the fan will undoubtedly be prolonged.

Hydroelectric power has become the most promising source in the power sector to sustain the growth of any nation. In any hydroelectric power plant, the hydraulic turbine plays a vital role which affects the overall performance of the plant and if utilized at suboptimal level, may lead to the loss of useful head. So, it becomes vital to predict the behavior of the hydro-turbine under actual working conditions. Francis turbines are the most well-known water turbines being used today. The Francis turbines works in water depths from 10 to 650 m (33–2133 ft) and are fundamentally utilized for electric power generation. This research consists of a simulation process and experimental research in order to compare both of the results. The geometry is modelled using the CATIA software and transferred into Ansys for the analysis. All the main parts that are included in the Francis turbine educational kit at the Universiti Kuala Lumpur Malaysian Spanish Institute such as the spiral casing, the runner blade, guide vane and the draft tube is constructed in the 3D model. The highest accuracy for the Francis turbine occurs at 1300 RPM and the highest inaccuracy percentage is within 30% and the lowest inaccuracy percentage is within 2%.

In this paper, we developed a compact pump reinforced by ceramics structure. In order to reduce the internal leakage, we developed a ceramics reinforcer for the pump-casing to suppress the deformation of the casing under high pressure, and devised the structure using bearing balls which can adjust the gap between the gear and the casing precisely. To evaluate the internal leakage, we used the internal leakage resistance which indicate the difficulty of internal leakage. Internal leakage resistance of developed pump is 3.39 × 1013Pa·s/m3 which means that the internal leakage loss of developed pump is 1/2.8 times that of previously developed pump.

The article presents a methodology for the construction of a numerical model of a gear pump with external meshing. The adopted load diagram reflects the operation of the pump in real conditions. The developed numerical model of the gear pump allows to determine the state of strain and strain and displacement. Simulation research was carried out using the finite element method. The calculations have been verified experimentally. Measurements of deformations of the pump casing were made while working, using resistance tensometry. The results obtained in numerical simulations were compared with the results of the experiment.

The aluminum-air battery receives more attention to applications in electronic mobile devices, transportation systems, and has a higher energy density than other metal-air batteries. However, the aluminum-air battery is still not widely commercialized due to unacceptably thermal issues. Hence, this study focuses on the development of an aluminum-air battery casing, studies the performance of the aluminum-air battery and thermal distribution analysis by using thermography. A single cell with dimensions of 10 cm × 10 cm × 3 cm with an anode area of 6.5 cm2 and an air cathode area of 6.5 cm2 is designed. In addition, 1 M of NaOH acts as the electrolyte of the battery. The aluminum-air battery temperature distribution is determined by a thermal imaging camera. The maximum temperature of 34 °C has been found as the reaction occurs. The result of the battery tests shows that the battery can produce a maximum voltage of 1.5 V and has a constant current value of 40 mA. The discharge rate of the battery indicates that one cell can operate for 10 h. Thus, the proposed design for the battery casing has functioned at the optimal condition.

A reactive hot spot concept was investigated for fine fragmentation of a structural reactive material (SRM) solid under explosive loading to augment air blast through rapid reaction of fine SRM fragments. Micro-sized MoO3 particles were distributed in a particulate aluminum base in 10Al + MoO3, which was consolidated into a full-density solid. The SRM solid was made of a thick-walled cylindrical casing containing a high explosive. Intermetallic reactions of micro-sized MoO3 and nearby Al under explosive loading created heat and gas products to form microscale hot spots that initiated local fractures leading to fine fragments of the rest of Al. Experiments in a cylindrical chamber demonstrated the presence of a large amount of fine Al fragments, whose prompt reaction after detonation significantly enhanced the primary and near-field blast wave, thus verifying the concept.

Airworthiness standards require a fire resistance demonstration for aircraft or helicopter engines to obtain a type certificate. This demonstration relies on tests performed with prototype engines in the late stages of the development. In these tests, a propane or a kerosene standardized flame with imposed burnt gas temperature and heat flux is placed next to the engine casing during a given time. The aim of this work is to provide a better characterization of a kerosene/air certification burner in order to reach a better understanding of the thermal environment during fire tests.

The testing and inspection of fans is a crucial task at the stages of designing and prototyping as well as in terms of future exploitation. In case of machines performing rotational movement, the scope of research is very broad and concerns strength tests, vibration diagnostics, acoustic test, and flow tests. The article presents the issue of studying vibrations of chosen elements of a fan with special regard to the casing and flow tests of the fan itself. The tests were carried out both on the actual object and numerically.

The rectification columns of oil and gas processing and petrochemical enterprises play a leading role in the production of intermediate and finished products. During their operation, column apparatuses are exposed to the operating load as well as to the corrosive working environment. All the above factors cause the development of the degradation processes in metal and its premature wear. Therefore, there is a problem of increasing the service life of the equipment, taking into account the factors that affect the operational properties of the equipment at all stages of its life cycle. The impact of the typical for such a stage as the production of installation works on the installation of column equipment in the design position has not been sufficiently studied. This implies the task of verifying the hypothesis of the effect of installation loads on the geometric parameters of the columns after a certain period of operation of the equipment. In this paper, we investigate the relationship between the maximum loads on the column apparatus casing that arise during the installation of equipment and the areas of increased corrosive wear revealed by measuring the wall thickness during technical diagnostics. Based on the research results, certain measures have been developed to eliminate or reduce the negative impact of installation loads.