Contents
Academic literature on the topic 'Statistisk processtyrning'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Statistisk processtyrning.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Dissertations / Theses on the topic "Statistisk processtyrning"
Hassan, Sara. "IMPLEMENTERING AV STATISTISK PROCESSTYRNING VID SMÅ SERIER." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-27810.
Full textStatistical process control, SPC, is a widely used technique for quality improvements by companies all over the world. The current trend in manufacturing organizations is directed towards shorter productions runs, which cause problems when applying traditional statistical methods developed for SPC on mass production runs. The critical factors for a successful implementation of SPC on short runs are still not fully explored and require further research. The main purpose of this study was to present a conceptual framework that illustrates the successful implementation of SPC in organizations with short runs and extensive product portfolio. In order to answer the research questions, a case study research methodology with both quantitative and qualitative methods was used. Participant observations and a workshop including 15 participators were performed in order to identify existing process variability’s and current state of the studied production processes. Three product families and key quality characteristics of each product were chosen to be monitored in control charts, based on scrap costs and staff experiences of the production process. A measurement system analysis was used to determine if the gauges, used to make measurement quality controls, were capable. Control charts were constructed and adjusted to short production runs. Statistical analysis was then made on the information gathered through the control charts to determine if statistical tools within SPC was useful for quality improvements on short production runs. Also a qualitative benchmark was performed with four manufacturing companies to take part of their experiences and knowledge related to the implementation and application of SPC. The findings indicate that the studied organization needs to improve working methods related to quality inspections and monitoring of the production processes. The organization also needs to improve the measurement system and make an extensive work of improvement to reduce the many identified special causes of variation that affects the processes and product quality, before implementing SPC in the organization. Findings showed that SPC tools and techniques successfully can be adopted to improve short run production processes when using standardized control charts for different product types. Short run production processes involve more complex statistical analysis which could inhibit the success of an implementation of SPC. The analysis of the qualitative and quantitative findings resulted in a framework including 15 critical success factors for the implementation of SPC in short production runs. All the following critical success factors should be taken into account by organizations with short runs that aspire a successful implementation of SPC: (1) Be ready to make a cultural change including the recognition of the importance of SPC within the whole organization, (2) Communicate a clear goal and long-term strategy, (3) Create motivation and commitment from top management to operators on the shop floor, (4) Select a SPC coordinator, (5) Introduce a training programme with feedback from start, (6) Create cross-functional teams, (7) Stimulate cooperation and participation within the work of improvements, (8) Ensure a capable measurement system, (9) Perform a pilot project with enthusiastic employees, (10) Identify critical processes, product families and key quality characteristics, (11) Focus on exploring process behaviors, (12) Construct standardized control charts, (13) Interpret and analyze control charts according to Montgomery’s method for statistical analysis, (14) Attempt to obtain processes in control, (15) Perform continuous follow ups.
Hägglund, Caroline, and Oscar Jonsson. "Tillståndsbaserat underhåll av spårväxlar genom statistisk processtyrning : En fallstudie enligt DMAIC." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-75049.
Full textSpårväxlar, som är en kritisk komponent på den svenska järnvägen, har ett eftersatt underhållsbehov som motsvarar en kostnad som är tre gånger större än den årliga underhållskostnaden. Från 2017 till 2018 ökade rapporteringen av funktionsfel i spårväxlar med 38 % och ungefär en tredjedel av funktionsfelen var tågstörande fel som orsakar merförseningar i tågtrafiken. Syftet med examensarbetet är att presentera rekommendationer för hur uppkomsten av tågstörande fel i spårväxlar kan reduceras genom tillståndsbaserat underhåll. Tillståndsbaserat underhåll är en kostnadseffektiv strategi som ämnar att övervaka och planera underhållsåtgärder efter tillståndet i enheten och är lämplig vid fjärrstyrd övervakning. För att uppfylla examensarbetets syfte delades projektet upp i tre delmål som besvarades genom tillämpning av problemlösningsmetoden DMAIC (Define, Measure, Analyse, Improve och Control). Det första delmålet innefattade stegen Define och Measure och ämnade undersöka vilket funktionsfel som orsakat flest antal merförseningsminuter per fel. Orsakskategorier till tågstörande fel analyserades där Materialutmattning/Åldrande samt Komponent trasig hade ett stort antal tågstörande fel och merförseningsminuter. Orsakskategorierna bröts ner till komponentnivå varav funktionsfel i Växellåda identifierades att orsaka flest antal merförseningsminuter per fel. Resultatet från Delmål 1 samt de två stegen Define och Measure användes därefter till Delmål 2. Det andra delmålet innefattade steget Analyse och ämnade att undersöka om det identifierade funktionsfelet i Växellåda kunde förutspås. Detta undersöktes genom larm från en av Trafikverkets befintliga databaser. Utifrån en grafisk analys av larmen kunde inget samband identifieras mellan funktionsfelet i Växellåda och larm från databasen. Därför undersöktes istället om funktionsfel i Växellåda kunde förutspås genom styrdiagram baserat på omläggningstid. Statistisk processtyrning är lämpligt vid övervakning av processer i realtid, men i detta examensarbetes analys användes historisk data från 2018. Den tillgängliga data hade brister i kvalitet till följd av trunkering av omläggningstiden. Trunkeringen innebar att decimalerna har avlägsnats. I styrdiagrammen påvisades larm där den befintliga databasen inte innehöll larm. Dessutom påvisade data på omläggningstiden från flera spårväxlar signifikant autokorrelation vilket påverkar beräkning av styrgränserna. Resultatet var således svårt att tolka på grund av trunkering och autokorrelerade data. Grafisk analys av omläggningstider och medelvärdet av omläggningstiderna indikerade att 69 % av spårväxlarna hade ett troligt samband mellan funktionsfel i Växellåda och omläggningstiden. Det tredje delmålet innefattade stegen Improve och Control och ämnade att upprätta rekommendationer för hur uppkomsten av funktionsfel i spårväxlar kan reduceras. Analysen i föregående delmål resulterade i följande rekommendationer: • Öka mätnoggrannheten vid mätning av omläggningstid, • Upprätta styrdiagram för omläggningstiden utifrån statistisk processtyrning och identifiera orsaken till autokorrelerade data, och • Förbättra inrapportering av funktionsfel.
Kabel, Daan, and Joel Grip. "Implementering av statistisk processtyrning för små- och medelstora företag : En fallstudie enligt DMAIC." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-65164.
Full textGans, Jesper, and Kenneth Ekström. "Implementering av digitalt mätsystem & statistisk processtyrning : Fallstudie på ett tillverkande SMF inom fordonsindustri." Thesis, KTH, Hållbar produktionsutveckling (ML), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297773.
Full textThe automotive industry is possibly one of the ones with the highest standards and lowest tolerances for errors. To have a production that fulfils the high demands from customers, OEMs must work diligently with reducing errors, not just in-house but across the whole value chain including suppliers to make sure their products can raise to the high demands set out. By using methods such as Statistical Process Control (SPC) and Measurement System Analysis (MSA) along with Gage R&R, it is possible to create products and parts with errors less thanfour per million manufactured parts. To help with improving the measurement taking and analytics, modern digital systems are recommended. In this report, a case study is created to study how small- and medium size denterprises (SMEs) can implement digital systems for measurement and production analytics from Mitutoyo, MeasurLink and QuickImage. The report also studies how digitalisation can simplify daily quality and process improvement processes while simultaneously making companies more competitive. This case study is performed on a SME, Marcus Komponenter AB, in Järna, Sweden who manufactures fasteners and custom ordered parts, and is a supplier to companies such as Scania and Volvo Trucks. Supervising the project is the Swedish Royal Institute of Technology (KTH) in Södertälje. The report is researching previous studies regarding quality and quality management among the main subjects, SPC and MSA. Complementing the studies, some background on digitalisation is given and an attempt at defining what digitalisation and Industry 4.0 is and how it can be applied to SMEs. The final part of the theory chapter goes over contemporary studies regarding digitalization, SPC as well as previous studies at Marcus Komponenter. For the analysis and discussion parts of the report, the findings that were found at Marcus Komponenter are combined with what was learned in the theory chapter. The conclusions were that there are good possibilities to start working with digitalisation now, at least regarding measurement and production analytics. However, the road there will require a lot of work and time as well as some investments but can increase competitiveness. To help implement digital technologies and manage the system, it is recommended to hire a measurement technician/supervisor or an SPC consultant to help guide companies. If technologies are simply bought but not used proactively, the investment will not make sense as SPC relies on continuous feedback to be useful. Markus Komponenter is constantly working on digitization based on their conditions. Implementing statistical process control should be a natural next step in digitization. This technical assignment shows that it is entirely possible for Marcus komponenter to continue their digitization and implement statistical process control to a greater extent, but it will require them as well as other SME:s to work lean and use their resources in a clever way.
Larsson, Kerstin, and Josefina Lundmarck. "Målinriktad SPS - en utredning i processtabilitet." Thesis, Linköping University, Linköping University, Department of Management and Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17390.
Full text
Det statistiska kvalitetsverktyget Statistisk Processtyrning, SPS, introducerades på BT Products AB i Mjölby utifrån en specifik implementeringsprocess. Introduktionen utfördes i en målningsprocess och genom detta arbete kunde aktuell process utvärderas och orsaker bakom eventuell urskiljbar variation eftersökas. I gällande process målas gods till eldrivna truckar svarta genom elektrostatisk pulvermålning, där eftersträvad färgskikttjocklek är 70 µm. Målningen utförs automatiserat av fyra robotar och för att erhålla kunskap om processens uppförande studerades och analyserades utfallet statistiskt utifrån en bestämd kvalitetsindikator, färgskikttjockleken. Data samlades in utifrån denna indikator genom kontinuerlig mätning på utvalt objekt och med hjälp av en mätmall för att erhålla jämförbara observationer. Tillförlitligheten hos insamlad data analyserades och observationerna uppvisade en normalfördelning och slumpmässighet. En hög grad av autokorrelation sågs dock, varför transformation av data krävdes innan fortsatta studier kunde utföras. I och med denna transformation erhölls oberoende och därmed tillförlitliga residualer, vilka studerades i styrdiagram för att information om processens uppförande över tiden skulle erhållas. Observationerna är individuella och anges som variabeldata, varför stora skiftningar i processen studerades i x‑ och MR-diagram och små skiftningar i EWMA-diagram. Vid studie av dessa diagram kunde såväl alarm som trender identifieras och processen ansågs därmed vara instabil. Dessa företeelser antogs vara resultatet av urskiljbar variation, orsakad av kontrollerbara faktorer. I den efterföljande processutvärderingen kom därför arbetet att fokusera på identifikation av dessa faktorer. För denna identifikation sattes en fokusgrupp samman, vilka listade möjliga faktorer i ett Ishikawadiagram utifrån de sju M:en.
Uppkomna faktorer testades utifrån främst tre olika metoder; tvåfaktorförsök, enfaktorförsök och loggning. Faktorförsöken genomfördes genom målning av testplåtar, där skillnad i färgskikttjocklek beroende på vald faktornivå studerades. Loggning av faktorer utfördes parallellt med produktion, varpå dessa värden ställdes mot registrerade värden på färgskikttjockleken i en ANOVA- eller korrelationsanalys. Utifrån resultatet av dessa tester delades undersökta faktorer in i Signifikanta, Delvis signifikanta, Eventuellt signifikanta och Ej signifikanta. De faktorer som ansågs vara signifikanta är Fluidisering och Pulverbatch, vilka kan vara bidragande orsaker bakom den urskiljbara variationen som identifierats. Fluidiseringen har periodvis varit undermålig i ett av de pulverkök som förser robotarna med pulver, något som kan förklara uppvisad låg korrelation mellan robotarna och den höga nivå av autokorrelation som skådats. Vid ett test med fyra olika säckar från två olika batcher sågs även en varierad batchhärkomst påverka resultatet, med en skillnad i färgskikttjocklek på mellan 10 och 20 µm på testplåten. De Delvis signifikanta faktorerna, så som injektorplugg, elektrod och munstycken, kan påverka utfallet vid en hög grad av förslitning och troligen fås störst inverkan i de fall då dessa samverkar. Genom att utföra rekommenderade åtgärder beträffande de signifikanta faktorerna, med avseende på att minska variationen, kan processen åter studeras och utredas. Beroende på utfall kan en stabil process förbättras och i annat fall söks nya källor till variation.
The statistical quality tool Statistical Process Control (SPC) was introduced at BT Products AB in Mjölby following the process of SPC implementation. The current process is a powder coating process where parts for powered trucks are painted black. The electrostatic powder coating is performed by four automatized robots and the desired layer thickness is 70 µm. The process has been evaluated from a quality characteristic, specified as the layer thickness, and special causes behind variation were identified. Data has been collected continuously from the process by measuring objects in the production, using a self-developed measurement template to receive comparable data. Statistical tools have been used to evaluate whether the data were reliable or not. A normal probability plot confirmed that the observations were normally distributed and a scatter plot established randomness. Autocorrelation was detected and the data had to be transformed, why the independent and reliable residuals were used in the subsequent analysis. Control charts were used to study the process over time, where individual x- and MR-charts detected large shifts in the process, while EWMA-charts detected small shifts. Alarms, trends and abnormal patterns were identified in these control charts, which led to the conclusion that the process could be considered out of control. The special causes behind this variation were assumed to stem from controllable factors and the work was therefore focused on identifying these special causes.
Factors were listed in an Ishikawadiagram by a focus group and tested using mainly three different methods. Design of experiments was used to test a two factorial design, and single factors were tested by one-factor-tests. A sheet metal was painted in both test methods and the difference in layer thickness, dependent on chosen level of the factor, was studied. Other factors were logged parallel to the production. Additional observations were compared to the registered layer thickness on parts and the relation analysed using ANOVA- or correlation analyses. Examined factors from these tests were divided and categorized into Significant, Partially significant, Possibly significant and Not significant. Fluidisation and powder batch were identified as significant factors and thereby possible causes behind the identified variation. The fluidisation in one of the powder containers has at times been misbegotten, something that can explain the high level of autocorrelation and the low level of correlation between the robots. When testing the batches, four sacks from two different batches were used and a large difference in layer thickness was observed depending on powder origin. A high degree of wear of the partially significant factors, as injector nozzle, electrode and gun nozzle, could affect the result, but they likely have the largest impact when collaborating. By performing recommended actions, in an attempt to reduce the variation on the basis of the significant factors, the process once again can be studied and evaluated. Depending on the result, a stable process can be improved, alternatively, new sources behind variation identified.
Åklint, Peter. "Övergripande kvalitets och kapabilitets granskning av produktionsprocessen – en implementering av SPS. : Overall Quality and Capability Study of the Production Process – an Implement of SPC." Thesis, Linköping University, Department of Management and Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10432.
Full textQuality was earlier only an issue for the company’s quality departments but today is the entire organization involved in quality- and improvements work. With the customers in focus, both external and internal, quality and improvement work should be integrated in the daily activities. The management shall state goals and visions together with a policy. Through participation the correct requirements for a successful work are created.
With SPC, statistics process control, there is an opportunity to perceive variations in the process and with the correct tools make it stable. Examples of tools that can be used are the seven QC – tools and the PDCA – cycles, which are presented more detailed in the report.
By using SPC and the information given by it, a measure of the process capability within fixed tolerances on the produced parts can be achieved.
The analysis in this report has been made in order to verify the capability and variations in the measuring system used within a selected production sector.
Hernandez, Andrea, and Anders Bergman. "Kvalitetskontroll av utskrifter från Kodak Approval XP4." Thesis, Högskolan Dalarna, Grafisk teknik, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:du-3571.
Full textHansson, Jonatan, and Jonas Duong. "Studie av process och maskinduglighet på Electrolux Laundry Systems plåtberedningsmaskiner." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-84864.
Full textHjälte, David. "Mot Industri 4.0 genom statistisk dataanalys : En studie om positionen av stansade hål vid Scania Ferruforms saidobalkstillverkning." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-85648.
Full textThe fourth industrial revolution, also called Industry 4.0 is powered by several technologies which result in digitalization and automatization of industrial processes. The concept includes the application of big data and advanced analytics, which are said to provide great opportunities for quality improvements. For such a transition to take place, the ability to handle data is crucial. Despite this, many companies today show a lack of use of data to drive decision-making. The question is how companies can manage data and ultimately transition towards Industry 4.0. To research this topic this thesis has been carried out as a case study of a punching process at Scania Ferruform. Through a literature review, quantitative data collection, as well as observations and interviews, the thesis examined the current use of data in the process. Subsequently, data were examined with statistical tools to illustrate how data can be managed in a process to attain increased knowledge about causes of deviations. Lastly, the thesis explored future work towards Industry 4.0. Analysis tools have been used to analyse over 39 000 data points. The result of the study shows that there are opportunities for development in terms of collection, quality and use of data. A framework of how Ferruform should manage data in order to extract new knowledge from its processes is presented. Furthermore, an action plan is presented for a transition towards Industry 4.0. Finally, recommendations are given for further studies. The result of the thesis will be helpful for Ferruform in its transition towards more efficient processes and the technical development of which the company strives towards.
Rybank-Högberg, Peter. "Reducera variationer inom kemisk processindustri : Utfört på Nouryon Site Stockvik." Thesis, Luleå tekniska universitet, Produkt- och produktionsutveckling, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-74191.
Full text