Stora Enso Kvarnsveden är ett pappersbruk lokaliserat vid Dalälven i Kvarnsveden. Bruket har för tillfället två producerande maskiner och detta arbete behandlar en av dem, vilken är PM12. På PM12 har man problem med oljeläckage i maskinens torkparti. Läckagen uppstår genom de lagerhus som finns för att bära upp torkpartiets valsar. I detta arbete har man undersökt vad läckagen beror på med fokus på dess lagertätningar. Syftet och målet med detta arbete har varit att utreda varför läckagen uppstår samt att generera koncept för att minska eller helt eliminera läckagen. Arbetet har innefattat diverse mätningar och utredningar för att komma till rätta med problemet. En litteraturstudie har genomförts för att identifiera felorsaker samt lösningar. Koncept har genererats utifrån studien samt de mätningar som utförts. Man har inte under arbetets gång helt kommit fram till vad läckagen beror på men man har kommit en bra bit på vägen. Förslag till fortsatt arbete har getts där det rekommenderas mer specifikt vilka typer av mätningar som bör genomföras samt de koncept man som bör bygga vidare på. / Stora Enso Kvarnsveden is a paper mill located at Dalälven in Kvarnsveden. The utility currently has two producing machines, and this study deals with one of them, which is PM12. At PM12 there is a problem with oil leaks in the machine's drying section. Leakage occurs through the bearing houses who are there to support the dryer's rollers. In this study, it has been investigated what the leakage is due to focusing on its bearing seals. The purpose of this study has been to investigate why leakage occurs and to generate concepts to reduce or eliminate leaks. The study has included various measurements and investigations to address the problem. A literature study has been conducted to identify causes and solutions. Concepts have been generated from the literature study as well as the measurements that have been taken. After this study it´s not fully realized why the leakage occurs, but it had come a long bit on the way. Proposals for continued work have been given, where it is recommended more specifically what kind of measurements that should be done and the concepts that should be further developed.

Radial lip seals are used to prevent leakage between machine elements in many industrial applications. During operation, fluid film between seal lip and shaft surface generates a pressure distribution on the lip which is elastically deformed due to hydrodynamic pressure. Surface roughness parameters in terms of moments of height profile distribution (rms roughness, skewness and kurtosis) affect the rate of oil leakage. A computer program is developed for elastohydrodynamic analysis of radial lip seals. Both the fluid mechanics of the lubricating film and the elastic deformation of the lip are taken into consideration to determine the hydrodynamic pressure distribution and the oil flow through the seal lip. The effect of shaft surface roughness on hydrodynamic analysis is taken into account by using average Reynolds equation with flow factors. For non-Gaussian surfaces, the modified flow factors are used to investigate the effects of skewness and kurtosis on the oil leakage. Numerical tests are performed for different skewness, kurtosis and initial seal tightness values. Results show that when a seal is mounted with a high initial tightness, the hydrodynamic pressure developed is not enough to deform the lip to form a fluid film between the shaft and the seal lip. It is observed that for the same rms roughness and skewness, the side flow rate increases as the kurtosis value increases. However, for the same rms roughness and kurtosis values, the side flow rate decreases for all skewness values.

Duas metodologias que podem ser utilizadas na localização de defeitos em cabos isolados de alta tensão do tipo Oil Filled (OF) foram analisadas. As metodologias descritas têm como princípio a localização de vazamentos de óleo, ou seja, todo defeito seguido de vazamento de óleo poderá ser localizado a partir das mesmas. A primeira metodologia é baseada no congelamento dos cabos OF, com a linha desenergizada, a fim de localizar vazamentos de óleo de cabos OF a partir de 300 litros por mês. A segunda metodologia é baseada na utilização de traços de gás perfluorcarbono Perfluorocarbon Tracer (PFT), através de um sistema montado com equipamentos que permitem realizar a localização de vazamentos de óleo de cabos OF a partir de 100 litros por mês, sem a necessidade de desligamento da linha subterrânea. Esta dissertação propõe algumas melhorias na metodologia do congelamento e apresenta as primeiras experiências de utilização do PFT no Brasil para localização de vazamentos de óleo. / Two methods that can be used to locate faults in Oil Filled (OF) cables were analyzed. The methods described have the principle of oil leak location. All defects followed by oil leakage can be located using the same. The first method is based in OF cables freezing, with the line outage, in order to locate oil leaks from 300 liters per month and above. The second method is based on the use of tracer gas - Perfluorocarbon Tracer (PFT) and devices that allow to perform the location of oil leaks from 100 liters per month, without the need of underground line outage. This paper proposes some improvements for the freezing method and presents the first experiments in Brazil using PFT to locate oil leakage.

Duas metodologias que podem ser utilizadas na localização de defeitos em cabos isolados de alta tensão do tipo Oil Filled (OF) foram analisadas. As metodologias descritas têm como princípio a localização de vazamentos de óleo, ou seja, todo defeito seguido de vazamento de óleo poderá ser localizado a partir das mesmas. A primeira metodologia é baseada no congelamento dos cabos OF, com a linha desenergizada, a fim de localizar vazamentos de óleo de cabos OF a partir de 300 litros por mês. A segunda metodologia é baseada na utilização de traços de gás perfluorcarbono Perfluorocarbon Tracer (PFT), através de um sistema montado com equipamentos que permitem realizar a localização de vazamentos de óleo de cabos OF a partir de 100 litros por mês, sem a necessidade de desligamento da linha subterrânea. Esta dissertação propõe algumas melhorias na metodologia do congelamento e apresenta as primeiras experiências de utilização do PFT no Brasil para localização de vazamentos de óleo. / Two methods that can be used to locate faults in Oil Filled (OF) cables were analyzed. The methods described have the principle of oil leak location. All defects followed by oil leakage can be located using the same. The first method is based in OF cables freezing, with the line outage, in order to locate oil leaks from 300 liters per month and above. The second method is based on the use of tracer gas - Perfluorocarbon Tracer (PFT) and devices that allow to perform the location of oil leaks from 100 liters per month, without the need of underground line outage. This paper proposes some improvements for the freezing method and presents the first experiments in Brazil using PFT to locate oil leakage.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-30T17:11:57Z No. of bitstreams: 1 MORGANA DE VASCONCELLOS ARAÚJO - DISSERTAÇÃO PPGEQ 2014..pdf: 6485490 bytes, checksum: ac573f517948e0ae4fa9b0adcf3f0f41 (MD5) / Made available in DSpace on 2018-04-30T17:11:57Z (GMT). No. of bitstreams: 1 MORGANA DE VASCONCELLOS ARAÚJO - DISSERTAÇÃO PPGEQ 2014..pdf: 6485490 bytes, checksum: ac573f517948e0ae4fa9b0adcf3f0f41 (MD5) Previous issue date: 2014-07-24 / CNPq / Capes / Diante do número de acidentes com dutos na indústria petrolífera, diversas pesquisas vêm buscando o aperfeiçoamento das tecnologias de detecção de vazamento, fazendo-se necessário o conhecimento do comportamento do(s) fluido(s) no interior da tubulação. O trabalho tem como objetivo geral o estudo termofluidodinâmico do escoamento água-óleo em uma conexão tê na presença de vazamento. Para isto, foi construído um domínio tridimensional e foi simulado o escoamento não isotérmico de água testando-se os modelos de turbulência k-Ɛ padrão, SST e RNG k-Ɛ e utilizando as equações da conservação de massa, momento e energia. Foram simulados os escoamentos bifásicos de água-óleo em uma conexão tê com vazamento, variando-se a fração volumétrica de óleo e as temperaturas das misturas nas seções de entrada. Comparando os perfis de velocidade e temperatura com dados experimentais observou-se que o modelo k-Ɛ padrão representou satisfatoriamente o comportamento do escoamento. Notou-se que quanto menor a fração volumétrica de óleo no escoamento, maior a pressão a montante do vazamento e que a região de encontro entre o duto principal e o duto secundário apresentou os maiores gradientes de pressão. / From the large number of accidents involving pipelines in the oil industry, many researcher have the objective of improving the tecnologies of leak detection, where the knowledge of the behavior (s) fluid (s) inside the pipe is necessary. The work aims to describe the thermofluid dynamics study of oil-water flow in a pipe with tee junction and with the presence of leakage. For this, a three-dimensional domain was built and it was simulated the nonisothermal flow of water by testing models of turbulence k-Ɛ standard, SST e RNG k-Ɛ, using the equations of conservation of mass, momentum and energy. Comparing the profiles of velocity and temperature with experimental data, it were observed that the k-Ɛ standard model well represented the flow pattern behavior satisfactorily. The water-oil two-phase flow in a tee junction with leakage was simulated, varying the volume fraction of oil mixtures and temperatures of the input sections. It was noted that the smaller the volume fraction of oil in the flow, the greater the pressure upstream of the leak and the region where the main duct is linked to the secondary duct showed higher pressure gradients.

The majority of the vessels in the commercial fleet utilize oil lubricated stern tubes. Unfortunately, this brings about a risk of oil leaking from the stern tube into the marine environment if the stern tube seal would become worn or damaged by foreign materials. Previous studies concluded that, on average, 2.6 litres of oil per day leak out from the stern tube of ships. This essay has investigated the causes that could increase the leakage rate from the stern tube by reviewing literature, interviewing experts, and sending out surveys with questions regarding the subject. The answers that were received painted a clear picture that it is impossible to get a perfect seal on a stern tube. The causes that could influence the leakage rate were design related, such as vibrations, the rotational speed of the propeller shaft, radial and axial movements of the propeller shaft, as well as external causes such as the quality of water and foreign materials, for example, fishing lines and nets. The question whether water lubricated stern tubes were a viable alternative compared to oil lubricated stern tubes was also investigated. The result was that the bearing on a water lubricated stern tube did not have as long lifespan as an oil lubricated bearing. / Majoriteten av fartygen i handelsflottan använder oljesmorda propellerhylsor för att smörja propelleraxeln. Tyvärr medför det en risk att olja kan läcka ut från hylsan om tätningarna skulle bli utslitna eller skadas av främmande föremål. Tidigare forskning har visat att cirka 2,6 liter olja per dag läcker ut genomsnittligen från fartyg i handelsflottan. Denna uppsats har utrett vad som kan påverka läckagemängden från en propellerhylsa genom att utnyttja intervjuer och enkätsvar. Svaren som framkom var att det är mer eller mindre omöjligt att få en perfekt tätning på en propellerhylsa. Saker som kan påverka läckagemängden var designfenomen som vibrationer, axiella- och radiella rörelser och varvtal på propelleraxeln, samt yttre påverkan som vattenkvalité och främmande föremål som fiskelinor och nät. I uppsatsen jämförs även vattensmorda propellerhylsor med fokus på livstid, kostnad och underhåll, med en oljesmord propellerhylsa. En slutsats är att det vattensmorda lagret inte har samma livstid som det oljesmorda.