Kuonankuljetusajoneuvojen ennakoivan huollon parantaminen

Opinnäytetyö tehtiin Outokumpu Stainless Oy:n Tornion tehtaalle. Työn tarkoituksena oli selvittää terässulaton prosessissa toimivien kuonankuljetusajoneuvojen tämänhetkinen kunto ja parantaa niiden ennakoivaa huoltoa mahdollisuuksien mukaan. Koneiden kunto selvitettiin analysoimalla niiden huoltohistoriaa ja haastattelemalla koneiden parissa työskenteleviä henkilöitä. Yksi työn tavoite oli myös selvittää jokaiselle koneelle mahdollinen peruskorjauksen tarve kunnon ja konekohtaisten kunnossapidon kustannusten perusteella. Lisäksi työssä pyrittiin selvittämään mahdolliset kehityskohteet. Työ aloitettiin käymällä läpi tuhansia rivejä koneiden kunnossapitotietoja, jotka haettiin kunnossapidon tietojärjestelmästä sekä SAP-järjestelmästä. Analysoitavaa kunnossapitotietoa oli käytettävissä koneiden käyttöönoton ajankohdasta nykypäivään saakka. Lisäksi työn alkuvaiheessa haastateltiin koneiden käyttö- ja huoltohenkilöitä. Haastatteluiden avulla saatiin parempi kuva koneiden sekä niiden huollon toiminnasta sekä kehityskohteista. Tässä vaiheessa tarkasteltiin myös koneiden nykyistä ennakkohuolto-ohjelmaa ja tutkittiin, miten sitä voisi tehostaa. Tutkimuksessa saatiin selville koneiden tämänhetkinen kunto ja niiden kunnossapidosta aiheutuneet kustannukset. Niiden perusteella saatiin myös määritettyä kullekin koneelle peruskorjauksen tarve. Lisäksi tutkimuksessa selvisi myös koneiden ja niiden huollon kehityskohteet. Työn konkreettisina tuloksina syntyi erilaisia taulukoita ja tilastoja, joista käy ilmi koneiden vuosittaiset varaosakulutukset ja kustannukset. Lisäksi luotujen työhistoriatilastojen perusteella kohdennettiin eniten vikaantuvat kohteet koneissa ja niiden rakenteissa. Näiden tietojen avulla koneille laadittiin nykyisen ennakkohuolto-ohjelman rinnalle erilaisia huoltoa ja koneiden kunnonvalvontaa tehostavia ohjelmia, kuten tarkastuksia.This study was done for Outokumpu Stainless Oy Tornio Works. The aim of this study was to find out the current condition of slag carriers and develop their proactive maintenance. The condition of the machines was clarified by analyzing their maintenance history and by interviewing the employees working with the machines. One of the aim of this study was also to find out potential need for the basic repair of each machine based on the condition and costs of the maintenance. In addition, the study aimed to find out the potential developments. The study was started by going through thousands of lines of machine maintenance data which was retrieved from the maintenance information systems. The data was available for the whole life cycle of the machines. The clarifying phase of the work also included interviews which were carried out with operating and maintenance employees to get a better picture of the machines, their maintenance activities and developments. The present proactive maintenance program of the machines was also examined and studied how it could be more effective. The study revealed the current condition of the machines and the costs of maintenance. On their basis it was also determined a need for the basic repair of each machine. In addition, the research revealed targets for the developments of the machines and their maintenance. As a result of the study, a variety of tables and statistics showing annual consumption of spare parts and the costs were created. The most faulty objects and structures of the machines were also found by using the maintenance history statistics. Using this information, multiple programs were designed to support the present proactive machine maintenance and condition monitoring

Viskositeetin vaikutus kaasua ja nestettä sisältävän virtauksen laskentaan dynaamisessa prosessisimulaattorissa

Gas-liquid two-phase flow occurs in safety valve calculations in the process industry. In order to size the safety valves reliably, the pressure drop calculations of the two-phase flow needs to be accurate. Two-phase flow is affected by many variables such as the viscosity. The aim of this thesis is to implement reliable and accurate calculation methods for viscosity and pressure drop for two-phase flows in a dynamic process simulator, ProsDS. Furthermore, the effect of viscosity on two-phase flow is studied. The literature part of this thesis consists of two main chapters. In the first chapter, the viscosity methods for gas and liquid phases are reviewed. In addition, the viscosity methods for petroleum fractions and crude oils are introduced. The second chapter focuses on the two-phase flow. Different variables related to two-phase calculations, flow patterns and pressure drop calculations methods are introduced. The effect of the viscosity on the two-phase flow is studied in the end of the second chapter. The applied part is also divided into two sections. In the first part, the most accurate and practical viscosity methods of FLOWBAT simulator were integrated into ProsDS. The methods were verified using experimental values presented in the literature. In the second part, several two-phase pressure drop methods were compared to the experimental values from the literature containing gas-liquid flows with various viscosities. Pressure drop methods of Lockhart-Martinelli, Müller-Steinhagen-Heck and Bandel gave the most accurate results and they were implemented into ProsDS. The methods were tested in a safety valve inlet piping case. The results of the simulated case differed significantly from each other. The inconsistency of the results indicates that it is difficult to predict two-phase pressure drops reliably.Kaasua ja nestettä sisältävää kaksifaasivirtausta esiintyy prosessiteollisuuden varoventtiilitapauksissa. Varoventtiilien mitoituksen luotettavuuden parantamiseksi kaksifaasivirtauslaskentaa tulisi tarkentaa. Kaksifaasivirtaus riippuu monista muuttujista kuten esimerkiksi viskositeetistä. Tämän diplomityön tarkoituksena on implementoida tarkat ja luotettavat menetelmät viskositeetin ja kaksifaasivirtauksen painehäviön laskemiseen dynaamisessa prosessisimulaattorissa, ProsDS:ssa. Lisäksi työssä tutkitaan viskositeetin vaikutusta kaksifaasivirtaukseen. Tämän työn kirjallisuusosa koostuu kahdesta pääluvusta. Ensimmäisessä luvussa vertaillaan erilaisia viskositeetin laskentamenetelmiä kaasuille ja nesteille. Lisäksi työssä tarkastellaan viskositeettimalleja öljyille. Toisessa luvussa keskitytään kaasua ja nestettä sisältävään kaksifaasivirtaukseen. Kappaleessa tuodaan esille kaksifaasilaskennan keskeiset muuttujat, eri virtaustyypit ja painehäviölaskentamenetelmät. Luvun lopuksi käsitellään viskositeetin vaikutusta kaksifaasivirtaukseen. Soveltava osa on jaettu myös kahteen osaan. Ensimmäisessä osassa ProsDS:än toteutettiin FLOWBAT-simulaattorin tarkimmat ja käytännöllisimmät viskositeetin laskentamenetelmät. Menetelmien tarkkuutta arvioitiin kirjallisuudesta saatujen arvojen avulla. Toisessa osassa vertailtiin useita kaksifaasipainehäviölaskentamenetelmiä kirjallisuudesta saatuihin painehäviöihin. Painehäviömenetelmistä Lockhart-Martinelli, Müller-Steinhagen-Heck ja Bandel osoittautuivat tarkimmiksi ja ne implementointiin ProsDS:än. Menetelmiä testattiin simuloidussa varoventtiilin tuloputkitapauksessa. Simuloidun tapauksen tulokset erosivat toisistaan huomattavasti. Täten voidaan todeta, että kaksifaasivirtauksen painehäviötä on vaikea ennustaa luotettavasti

Performance of the FMI cosine error correction method for the Brewer spectral UV measurements

Non-ideal angular response of a spectroradiometer is a well-known error source of spectral UV measurements and for that reason instrument specific cosine error correction is applied. In this paper, the performance of the cosine error correction method of Brewer spectral UV measurements in use at the Finnish Meteorological Institute (FMI) is studied. Ideally, the correction depends on the actual sky radiation distribution, which can change even during one spectral scan due to rapid changes in cloudiness. The FMI method has been developed to take into account the changes in the ratio of direct to diffuse sky radiation and it derives a correction coefficient for each measured wavelength. Measurements of five Brewers were corrected for the cosine error and the results were compared to the reference travelling spectroradiometer (QASUME). Measurements were performed during the RBCC-E (Regional Brewer Calibration Center – Europe) X Campaign held at El Arenosillo, Huelva (37∘ N, 7∘ W), Spain, in 2015. In addition, results of site audits of FMI's Brewers in Sodankylä (67∘ N, 27∘ E) and Jokioinen (61∘ N, 24∘ E) during 2002–2014 were studied. The results show that the spectral cosine error correction varied between 4 and 14 %. After that the correction was applied to Brewer UV spectra the relative differences between the QASUME and the Brewer diminished even by 10 %. The study confirms that the method, originally developed for measurements at high latitudes, can be used at mid-latitudes as well. The method is applicable to other Brewers as far as the required input parameters, i.e. total ozone, aerosol information, albedo, instrument specific angular response and slit function are available.This article is based upon work from the COST Action ES1207 “A European Brewer Network (EUBREWNET)”, supported by COST (European Cooperation in Science and Technology). This study was partially supported by the research projects CGL2014-56255-C2-1-R and CGL2014-56255-C2-2-R granted by the Ministerio de Economa y Competitividad from Spain

Detecting volcanic sulfur dioxide plumes in the Northern Hemisphere using the Brewer spectrophotometer, other networks, and satellite observations

This paper demonstrates that SO 2 columnar amounts have significantly increased following the five largest volcanic eruptions of the past decade in the Northern Hemisphere. A strong positive signal was detected by all the existing networks either ground based (Brewer, EARLINET, AirBase) or from satellites (OMI, GOME-2). The study particularly examines the adequacy of the existing Brewer network to detect SO 2 plumes of volcanic origin in comparison to other networks and satellite platforms. The comparison with OMI and 45 GOME-2 SO 2 space-borne retrievals shows statistically significant agreement between the Brewer network data and the collocated satellite overpasses. It is shown that the Brewer instrument is capable of detecting significant columnar SO 2 increases following large volcanic eruptions, when SO 2 levels rise well above the instrumental noise of daily observations, estimated to be of the order of 2 DU. A model exercise from the MACC project shows that the large increases of SO 2 over Europe following the Bárðarbunga eruption in Iceland were not caused by local sources or ship emissions but are clearly linked to the eruption. We propose that by combining Brewer data with that from other networks and satellites, a useful tool aided by trajectory analyses and modeling could be created which can be used to forecast high SO 2 values both at ground level and in air flight corridors following future eruptions

Role of ALD Al2O3 Surface Passivation on the Performance of p-Type Cu2O Thin Film Transistors

High-performance p- type oxide thin film transistors (TFTs) have great potential for many semiconductor applications. However, these devices typically suffer from low hole mobility and high off-state currents. We fabricated p-type TFTs with a phase-pure polycrystalline Cu2O semiconductor channel grown by atomic layer deposition (ALD). The TFT switching characteristics were improved by applying a thin ALD Al2O3 passivation layer on the Cu2O channel, followed by vacuum annealing at 300 degrees C. Detailed characterization by transmission electron microscopy-energy dispersive X-ray analysis and X-ray photoelectron spectroscopy shows that the surface of Cu2O is reduced following Al2O3 deposition and indicates the formation of a 1-2 nm thick CuAlO2 interfacial layer. This, together with field-effect passivation caused by the high negative fixed charge of the ALD Al2O3, leads to an improvement in the TFT performance by reducing the density of deep trap states as well as by reducing the accumulation of electrons in the semiconducting layer in the device off-state.Peer reviewe

Arterial stiffness and vascular complications in patients with type 1 diabetes: The finnish diabetic nephropathy (FinnDiane) study

While patients with type 1 diabetes (T1D) are known to suffer from early cardiovascular disease (CVD), we examined associations between arterial stiffness and diabetic complications in a large patient group with T1D.This study included 807 subjects (622 T1D and 185 healthy volunteers (age 40.6 ± 0.7 versus 41.6 ± 1.2 years; P = NS)). Arterial stiffness was measured by pulse wave analysis from each participant. Furthermore, information on diabetic retinopathy, nephropathy, and CVD was collected. The renal status was verified from at least two out of three urine collections.Patients with T1D without signs of diabetic nephropathy had stiffer arteries measured as the augmentation index (AIx) than age-matched control subjects (17.3% ± 0.6% versus 10.0% ± 1.2%; P0.001). Moreover, AIx (OR 1.08; 95% CI 1.03-1.13; P = 0.002) was associated with diabetic laser-treated retinopathy in patients with normoalbuminuria in a multivariate logistic regression analysis. The same was true for AIx and diabetic nephropathy (1.04 (1.01-1.08); P = 0.004) as well as AIx and CVD (1.06 (1.00-1.12); P = 0.01) in patients with T1D.Arterial stiffness was associated with microvascular and macrovascular complications in patients with T1D

In search of traceability : two decades of calibrated Brewer UV measurements in Sodankyla and Jokioinen

The two Brewer spectrophotometers of the Finnish Meteorological Institute at Jokioinen and Sodankyla have been operated according to the highest levels of the WMO/GAW (World Meteorological Organization/Global Atmosphere Watch) recommendations with rigorous quality control and quality assurance. The calibration of the instruments is based on annual recalibrations of primary standard lamps in the VTT MIKES Metrology National Standards Laboratory in Finland and an exhaustive measurement program with measurements of standard and working lamps in the on-site optical laboratories. Over the years, the maintenance of the calibration has produced data sets of approximately 2000 lamp scans for both instruments. An extensive re-examination of the lamp measurements and the response of the spectrophotometers was carried out. The primary standard lamps were found to age on an average rate of 0.3% per burn. The responsivity at wavelength 311 nm was found to exhibit both long-term and short-term changes. The overall long-term change was declining. In addition, abrupt changes of as large as 25% were detected. The short-term changes were found to fluctuate on time frames shorter than the interval between the measurements of the primary standard lamps. This underlines the importance of the use of more frequently measured working standard lamps.Peer reviewe

Atomic Layer Deposition of Photoconductive Cu2O Thin Films

Herein, we report an atomic layer deposition (ALD) process for Cu2O thin films using copper(II) acetate [Cu(OAc)(2)] and water vapor as precursors. This precursor combination enables the deposition of phase-pure, polycrystalline, and impurity-free Cu2O thin films at temperatures of 180-220 degrees C. The deposition of Cu(I) oxide films from a Cu(II) precursor without the use of a reducing agent is explained by the thermally induced reduction of Cu(OAc)(2) to the volatile copper(I) acetate, CuOAc. In addition to the optimization of ALD process parameters and characterization of film properties, we studied the Cu2O films in the fabrication of photoconductor devices. Our proof-of-concept devices show that approx- imately 20 nm thick Cu2O films can be used for photodetection in the visible wavelength range and that the thin film photoconductors exhibit improved device characteristics in comparison to bulk Cu2O crystals.Peer reviewe

Data flow of spectral UV measurements at Sodankylä and Jokioinen

The data flow involved in a long-term continuous solar spectral UV irradiance monitoring program is investigated and structured to provide an overall view on the multiphase process from data acquisition to the final products. The program employing Brewer spectrophotometers as measuring instruments is maintained by the Finnish Meteorological Institute (FMI) ever since the 1990s at two sites in Finland: Sodankyla (67 degrees N) and Jokioinen (61 degrees N). It is built upon rigorous operation routines, processing procedures, and tools for quality control (QC) and quality analysis (QA) under continuous development and evaluation. Three distinct levels of data emerge, each after certain phase in the data flow: Level 0 denoting raw data, Level 1 meaning calibrated data processed in near-real time, and Level 2 comprising of postprocessed data corrected for all distinguishable errors and known inaccuracies. The final products disseminated to the users are demonstrated to result from a process with a multitude of separate steps, each required in the production of high-quality data on solar UV radiation at the Earth's surface.Peer reviewe