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1

Failure analysis during the operation of offshore oil and gas structures

Ben Nengjun, Vytyaz Oleg, Jin Xin, Hrabovskyi Roman, Kopei Bogdan

Nafta-Gaz

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2023

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R. 79, nr 8

529--536

EN

: Failures caused by offshore oil and gas structures operations are investigated. This work is based on the description and analysis of real case studies of accidents on offshore stationary and floating platforms; it combines foundational knowledge and current research on the latest developments in the field. It was shown that strength characteristics of offshore reinforced concrete and steel elements change during operation and cause the accumulation of defects and damages. It was established that corrosive wear, corrosion-mechanical processes, and crack-like defects are the decisive causes of element failure. It was shown that up to 60–75% of all damages to and failures of offshore engineering facilities' steel structures occur due to the corrosion-mechanical influence of an aggressive environment and force loads. This means that issues of corrosion-mechanical failure of such structures have become an industrial-scale problem. It thus allows us to draw the following conclusions: improvement of steel offshore drilling platforms (ODPs) maintenance system involves the development of new models and methods of managing the operational reliability of these structures, aimed at making decisions that take into account the crack resistance and fatigue-corrosion strength of steel ODPs in contact with the corrosive-active environment. Only on the basis of such scientifically and economically grounded models can rational strategies be shaped for carrying out revisions of the ODPs technical condition, ensuring the necessary level of their reliability during the operation period. This investigation can be very helpful to improve the design and construction of more reliable and durable offshore stationary and floating platforms.

PL

W artykule omówiono uszkodzenia powstające w trakcie eksploatacji podmorskich złóż ropy i gazu. Niniejsza praca opiera się na opisie i analizie rzeczywistych przypadków wypadków na morskich platformach stacjonarnych i pływających, łączy ona podstawową wiedzę z bieżącymi badaniami nad najnowszymi osiągnięciami w tej dziedzinie. Wykazano, że charakterystyki wytrzymałościowe elementów betonowych i stalowych konstrukcji morskich w trakcie eksploatacji zmieniają się i kumulują wady i uszkodzenia. Ustalono, że decydującymi przyczynami uszkodzeń elementów są zużycie korozyjne, procesy korozyjno-mechaniczne oraz defekty spękaniowe. Wykazano, że do 60–75% wszystkich uszkodzeń i wypadków stalowych urządzeń morskich powstaje w wyniku korozyjnego i mechanicznego działania agresywnego środowiska oraz obciążeń siłowych. Oznacza to, że kwestie korozyjnego mechanicznego uszkodzenia takich konstrukcji stały się problemem na skalę przemysłową. Na tej podstawie można wyciągnąć następujące wnioski: doskonalenie systemu utrzymania morskich stalowych platform wiertniczych wiąże się z opracowywaniem nowych modeli i metod zarządzania niezawodnością eksploatacyjną tych konstrukcji, ukierunkowanych na podejmowanie decyzji uwzględniających odporność na pękanie oraz odporność na korozję zmęczeniową stalowych platform wiertniczych stykających się ze środowiskiem korozyjno-aktywnym. Tylko w oparciu o tego typu, naukowo i ekonomicznie ugruntowane modele, można kształtować racjonalne strategie przeprowadzania przeglądów stanu technicznego morskich platform wiertniczych, zapewniające niezbędny poziom ich niezawodności w okresie eksploatacji. Badania te mogą być bardzo pomocne w ulepszaniu projektowania i budowy bardziej niezawodnych i trwałych morskich platform, zarówno stacjonarnych, jak i pływających.

2

Analysis of a crash on a vehicle system by adjusting appropriate input parameters to manage energy absorption capacity for enhancing passenger safety

Dhamone Sagar Parashuram, Padmakumar Arunkumar

Acta Innovations

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2023

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no. 50

5--17

EN

The aim of the research is to develop a front bumper system that absorbs maximum impact energy as compared to the current bumper available in the market, Bumper design is based on increasing the area of the crumping zone to slow down the collision and observe the impacts taking place at the time of jerks and reduces the percentage of damage. To develop the system, the number of load cases tested numerically in passive safety simulation has increased significantly in recent years. The variety of applications may be divided into three main topics: structural crashworthiness of the whole car, passenger protection, and crashworthiness of components. Present theories and practices. To absorb impact, the front bumper of the car uses a spring-loaded system that is installed between the bumper and the support for the chassis structure. This system is made of metal and serves as the bumper's structural foundation. A honeycomb structure is being added to the bumper as a composite material together with a layer of galvanized iron as it is being created in this manner, which increases strength while weighing less. This arrangement design is suitable for psychoacoustics, varying velocity explicit analysis is performed with the approach of finite element analysis, experimental testing is carried out for the validation of the value and advanced manufacturing methods are implemented with statistical results, and one of the cheapest systems is developed as compared to the current bumper systems.

3

The causes of the damage to the bearing rope – failure analysis

Peterka Pavel, Krešák Jozef

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 2

231--236

EN

In our laboratory we quite often experience problems with the operation of steel ropes. There is a range of causes related to lifetime problems of ropes. These problems are related to poor quality of input material used for wire production, mixing of different wire strengths in the rope construction, improper roping of the rope into the hoist system, improper rope operation, improper rope design for a particular type of operation as well as unfair practices of vendors. The subject of the article is the analysis of the rope showing the combination of a large number of the above factors leading to the damage of the rope. During the operation of the cargo cableway, the hauling ropes were damaged in a very short time. The Z wires from the surface layer of the rope started to release from the rope. Subsequently, the wires were unwinding from the layer, they created visible protuberant waves, they were braking and dropping out from the rope. The hauling rope had to be replaced. Than the samples were taken from the rope in order to find out the cause of the rope damage. Mechanical, metallographic and fractographic measurements were performed on the rope. The metallographic and fractographic measurements revealed the material defects of the wires of the rope caused during manufacturing of the Z wires from the surface layer of the hauling rope. The mechanical tests revealed differences in the tensile strength grade the operator required compering to the tensile strength grade the vendor declared. The above mentioned problems unambiguously show that it is appropriate to introduce a mechanical control of the rope properties in advance to its deployment. Checks must be performed by an independent testing laboratory. This procedure overprices inputs needed for the rope replacement. On the other hand, it can reduce the costs when a poor quality rope is deployed. Some of our customers have already adopted this approach. It helped to the increase in the safety of the operation of the mechanisms and it eliminated the problems with exchange and climes on bad quality ropes.

4

Experience of the Crane Steel Wire Ropes Non-Destructive Tests

Peterka Pavel, Krešák Jozef, Vojtko Marek

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 4

157--163

EN

The non-destructive tests (NDT) of the steel wire ropes put on the crane pulley blocks comprise more than a half of our NDT services. The intensive utilization of cranes often leads to critical situations endangering health and safety at work. The operators are forced to provide safety use of the cranes due to new cranes constructions, new construction of the block pulley and put on the new steel wire rope constructions. The NDT tests of the crane steel wire ropes are coordinate by the Standard ISO 4309. We have experienced only the crane steel wire ropes with an individual wire rope core during our NDT tests so far. The visual NDT test usually used is ineffective to the steel wire ropes with this construction. Based on our previous experience it can be confirmed that surface ruptures are produced after the disintegration of wires inside of a rope; it often leads to the rope abruption during its operation. The reduction of the pulley block dimensions often leads to the problem of the multi-axis rope bending. This kind of the rope line in the pulley block causes the increase of the fretting fatigue of the wires and the rope strands. The same type of the stress is created when the dead ends of the rope are badly constructed.

5

Conveyor Failure Diagnostics using Sound Visualization Technique

Moravec M., Badida Miroslav, Jamborova Miroslava, Badidova Anna

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 4

144--150

EN

Sound visualization methods and techniques are currently applied in various fields to identify and locate individual sources of noise. Conveyor systems are used in various industrial plants. Conveyors require regular inspection and maintenance. In some operations, conveyor systems are difficult to access for the maintenance purposes. During their operation, conveyor systems contribute to increasing the noise levels. The increased noise emitted by a conveyor may signal the failure of a certain part of the system. Such failures can be identified by a sound visualization device and contribute to an effective maintenance of conveyor systems. The paper analyzes specific conveyor systems and identified potential failures of these conveyor systems by using sound visualization methods.

6

Numerical prediction of the effects of miniature channel shaped scratches on the fracture behaviour of wires for civil engineering applications using finite element analysis

Adewole K. K., Bull S. J.

Archives of Civil Engineering

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2014

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Vol. 60, nr 2

181--194

EN

The effects of the miniature channel-shaped scratches not detectable by the present inline electromagnetic defect detection system employed for wires’ surface defect detection on the fracture behaviour of the wires for civil engineering applications were investigated numerically. Finite element analysis revealed that both miniature channel-shaped across-the-thickness and across-the-width scratches change the fracture behaviour of the wires in terms of the fracture initiation locations and fracture process sequence. However, miniature across-the-thickness scratches does not affect the fracture shape of the wire while miniature across-the-width scratches changed the wires’ cup and cone fracture to a fracture shape with a predominantly flat fracture. These results provide an understanding of the fracture behaviour of wires with miniature scratches and serve as an alternative or a complimentary tools to experimental or fractographic failure analysis of wires with miniatures scratches which are difficult to carry out in the laboratory due to the sizes of the scratches.

7

Failure analysis of the Krosno water network

Pietrucha-Urbanik K., Studziński A.

Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska

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2012

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z. 59, nr 1/I

159-166

EN

In the article analysis of failures of the Krosno water network has been presented. In the work the analysis of the failure frequency for individual kinds of waterworks (main, distribution and water supply connections) on the example of the Krosno water network was also presented. An analysis based on exploitation data of the water network get from Municipal Services Office in Krosno in years 2005 - 2009 was carried out. In the work the analysis of the failures depended on the diversity of applied materials, age and diameters for individual kinds of waterworks was also presented.

PL

W pracy przedstawiono analizę awaryjności sieci wodociągowej Krosna. Zakres pracy obejmuje analizę wskaźników intensywności uszkodzeń przewodów magistralnych, rozdzielczych oraz przyłączy wodociągowych na przykładzie sieci wodociągowej Krosna. Analizę przeprowadzono na podstawie danych eksploatacyjnych sieci wodociągowej w latach 2005 - 2009, uzyskanych od MPGiK w Krośnie. Dokonano analizy awaryjności ze względu na zastosowany materiał, wiek oraz średnicę dla poszczególnych rodzajów przewodów wodociągowych.

8

Failure state of steel roof structure of the show-sports hall during assembly

Hotała E., Rykaluk K.

Archives of Civil and Mechanical Engineering

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2012

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Vol. 12, no. 1

41--48

EN

At the final stage of assembly of a steel truss grid over central part the show-sports hall, the heterogeneous cracks have been observed at about 65% of welds. Arisen failure hazard of the grid structure appeared already under the dead load, and after this the assembly works were stopped. An extensive analysis of different factors like: construction, execution, transport and assemble, supported by metallographic and ultrasonic tests, allowed to recognize the basic causes of the failure hazard. It was found that defective construction of the truss nodes, improper division of the structure into shop- prefabricated members and the negative effect of the both transport and assemble leaded to serious damage of the roof structure and showed the necessity of its strengthening.

9

FEM modeling of inter-turn short-circults in excitation winding of turbogenerator

Fišer R., Lavrič H., Bugeza M., Makuc D.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 3

49-52

EN

The paper presents an approach to modeling of shorted tums in rotor excitation winding of synchronous generator using FEM. It enables detailed analysis of magnetic field at several operating conditions under healthy and faulty states which are difficult to carry out by available measurement methods in industrial environment. Modeling of excitation winding faults is performed for a 156 MVA turbo generator operating in thermaI power plant. Since the level of diagnostic signal is considerably influenced by combination of many machine and operating parameters, an extensive analyses are needed to assure accurate healthy/faulty state predictions.

PL

Artykuł prezentuje podejście do modelowania zwartych zwojów w uzwojeniu wzbudzającym wimika generator synchronicznego przy utycie MES. Umożliwia to dokładną analizę pola magnetycznego w kilkunastu reżimach pracy z uwzględnieniem stanów awaryjnych i bezawaryjnych, która jest trudna do przeprowadzenia dostępnymi w przemyśle metodami pomiarowymi. Modelowanie uzwojenia wzbudzenia zostało wykonane dla turbogeneratora 156 MVA pracującego w elektrociepłowni. Ponieważ poziom sygnału diagnostycznego w sposób istotny poddany wpływowi kombinacji wielu maszynowych i operacyjnych parametrów, ekstensywne analizy są niezbędne aby zapewnić dokładne predykcje stanu awaryjnego.

10

Szybkie wykrywanie i dokładna lokalizacja awarii rozproszonych w sieciach SN

Żurowski J.

Wiadomości Elektrotechniczne

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2010

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R. 78, nr 11

27-30

PL

Opisano system zbierania, analizy i sposób prezentacji informacji uzyskanych z sieci dystrybucyjnej w celu poprawy parametrów jakościowych dostarczanej energii elektrycznej.

EN

The author describes a system of acquisition, analysis and presentation of information obtained from distribution network in order to improve quality parameters of supplied electric energy.

11

Hybrid approach to design optimisation: Preserve accuracy, reduce dimensionality

Kamola M.

International Journal of Applied Mathematics and Computer Science

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2007

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Vol. 17, no 1

53-71

EN

The paper proposes a design procedure for the creation of a robust and effective hybrid algorithm, tailored to and capable of carrying out a given design optimisation task. In the course of algorithm creation, a small set of simple optimisation methods is chosen, out of which those performing best will constitute the hybrid algorithm. The simplicity of the method allows implementing ad-hoc modifications if unexpected adverse features of the optimisation problem are found. It is postulated to model a system that is smaller but conceptually equivalent, whose model is much simpler than the original one and can be used freely during algorithm construction. Successful operation of the proposed approach is presented in two case studies (power plant set-point optimisation and waveguide bend shape optimisation). The proposed methodology is intended to be used by those not having much knowledge of the system or modelling technology, but having the basic practice in optimisation. It is designed as a compromise between brute force optimisation and design optimisation preceded by a refined study of the underlying problem. Special attention is paid to cases where simulation failures (regardless of their nature) form big obstacles in the course of the optimisation process.

12

Analiza awarii sprężarek przepływowych

Kryłłowicz W., Magiera R.

Pneumatyka

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2004

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nr 4

12-14

PL

W niniejszym artykule przeprowadzono analizę i klasyfikację typowych awarii sprężarek przepływowych pod kątem ich przyczyn. Analiza ta oparta jest na ponadtrzydziestoletnim doświadczeniu eksploatacyjnym i konstrukcyjnym. Przedstawiono ponadto przykłady typowych awarii.