Structural analysis and condition monitoring of grinding mills : a case study
Grinding mills are large rotating cylindrical steel vessels used to grind ore and minerals into finer particles. The mills are important parts of the mineral enrichment process and the grinding is the last step of the comminution process, where the particle size is reduced by a combination of abrasi...
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Luleå tekniska universitet, Drift, underhåll och akustik
2012
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ftluleatu:oai:DiVA.org:ltu-26441 2023-05-15T17:04:20+02:00 Structural analysis and condition monitoring of grinding mills : a case study Berglund, Filip 2012 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26441 eng eng Luleå tekniska universitet, Drift, underhåll och akustik Luleå Licentiate thesis / Luleå University of Technology, 1402-1757 http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26441 urn:isbn:978-91-7439-483-2 Local e3dd21a2-cbda-4907-be60-e04133a9af1f info:eu-repo/semantics/openAccess Other Civil Engineering Annan samhällsbyggnadsteknik Licentiate thesis, comprehensive summary info:eu-repo/semantics/masterThesis text 2012 ftluleatu 2022-10-25T20:51:12Z Grinding mills are large rotating cylindrical steel vessels used to grind ore and minerals into finer particles. The mills are important parts of the mineral enrichment process and the grinding is the last step of the comminution process, where the particle size is reduced by a combination of abrasion and impact.The rotation of the mill under loaded conditions can result in fatigue cracks. Fatigue cracks and associated failures have been identified as a major problem in mineral processing plants. The cracks lead to unpredicted and unplanned production stoppages for inspections and for repair and replacement of the cracked mill parts. This leads to increasing costs due to production loss, additional man-hours and spare parts.The purpose of the research presented in this licentiate thesis was to calculate the structural strains, stresses, displacements, etc. in grinding mills in operation, to prevent overloading, to calculate crack propagation speeds and critical crack lengths, and to develop new improved mills that would withstand the current loading. This research has also aimed to propose, develop and test methods for the detection and monitoring of fatigue cracks in mills during operation, in order to facilitate optimal maintenance decision-making based on current crack sizes.The performed research is a case study of the secondary pebble mills of LKAB, a mining company in northern Sweden. The mills are situated inside dressing plants KA1 and KA2 in Kiruna. To achieve the goals, a number of crack detection and monitoring methods were investigated and evaluated as to their ability to find and monitor fatigue cracks on the running mills. Measurements with wireless strain measurement equipment, infrared thermography and crack propagation sensors were performed on the mills in operation.A finite element model of a mill was developed to calculate the strains and stresses in the mill at any position in the mill and for any loading condition. A variety of spatial discretizations, boundary conditions, material ... Master Thesis Kiruna Northern Sweden Luleå University of Technology Publications (DiVA) Kiruna |
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Luleå University of Technology Publications (DiVA) |
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ftluleatu |
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English |
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Other Civil Engineering Annan samhällsbyggnadsteknik |
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Other Civil Engineering Annan samhällsbyggnadsteknik Berglund, Filip Structural analysis and condition monitoring of grinding mills : a case study |
topic_facet |
Other Civil Engineering Annan samhällsbyggnadsteknik |
description |
Grinding mills are large rotating cylindrical steel vessels used to grind ore and minerals into finer particles. The mills are important parts of the mineral enrichment process and the grinding is the last step of the comminution process, where the particle size is reduced by a combination of abrasion and impact.The rotation of the mill under loaded conditions can result in fatigue cracks. Fatigue cracks and associated failures have been identified as a major problem in mineral processing plants. The cracks lead to unpredicted and unplanned production stoppages for inspections and for repair and replacement of the cracked mill parts. This leads to increasing costs due to production loss, additional man-hours and spare parts.The purpose of the research presented in this licentiate thesis was to calculate the structural strains, stresses, displacements, etc. in grinding mills in operation, to prevent overloading, to calculate crack propagation speeds and critical crack lengths, and to develop new improved mills that would withstand the current loading. This research has also aimed to propose, develop and test methods for the detection and monitoring of fatigue cracks in mills during operation, in order to facilitate optimal maintenance decision-making based on current crack sizes.The performed research is a case study of the secondary pebble mills of LKAB, a mining company in northern Sweden. The mills are situated inside dressing plants KA1 and KA2 in Kiruna. To achieve the goals, a number of crack detection and monitoring methods were investigated and evaluated as to their ability to find and monitor fatigue cracks on the running mills. Measurements with wireless strain measurement equipment, infrared thermography and crack propagation sensors were performed on the mills in operation.A finite element model of a mill was developed to calculate the strains and stresses in the mill at any position in the mill and for any loading condition. A variety of spatial discretizations, boundary conditions, material ... |
format |
Master Thesis |
author |
Berglund, Filip |
author_facet |
Berglund, Filip |
author_sort |
Berglund, Filip |
title |
Structural analysis and condition monitoring of grinding mills : a case study |
title_short |
Structural analysis and condition monitoring of grinding mills : a case study |
title_full |
Structural analysis and condition monitoring of grinding mills : a case study |
title_fullStr |
Structural analysis and condition monitoring of grinding mills : a case study |
title_full_unstemmed |
Structural analysis and condition monitoring of grinding mills : a case study |
title_sort |
structural analysis and condition monitoring of grinding mills : a case study |
publisher |
Luleå tekniska universitet, Drift, underhåll och akustik |
publishDate |
2012 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26441 |
geographic |
Kiruna |
geographic_facet |
Kiruna |
genre |
Kiruna Northern Sweden |
genre_facet |
Kiruna Northern Sweden |
op_relation |
Licentiate thesis / Luleå University of Technology, 1402-1757 http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26441 urn:isbn:978-91-7439-483-2 Local e3dd21a2-cbda-4907-be60-e04133a9af1f |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766058408704737280 |