Wear of Grate Plates
This report describe the wear of the protruding areas on the sides of the grate plates in the grate-kiln process in the hematite pellet production in LKAB, Kiruna. The steel plates are exposed to a hostile environment with heat cycles and corrosive atmosphere. An evaluation of the plates was made in...
Main Author: | |
---|---|
Format: | Bachelor Thesis |
Language: | English |
Published: |
KTH, Materialvetenskap
2014
|
Subjects: | |
Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160603 |
id |
ftkthstockholm:oai:DiVA.org:kth-160603 |
---|---|
record_format |
openpolar |
spelling |
ftkthstockholm:oai:DiVA.org:kth-160603 2024-06-23T07:54:24+00:00 Wear of Grate Plates Martinsson, Johan 2014 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160603 eng eng KTH, Materialvetenskap http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160603 info:eu-repo/semantics/openAccess Grate plate wear Metallurgy and Metallic Materials Metallurgi och metalliska material Student thesis info:eu-repo/semantics/bachelorThesis text 2014 ftkthstockholm 2024-05-27T17:45:25Z This report describe the wear of the protruding areas on the sides of the grate plates in the grate-kiln process in the hematite pellet production in LKAB, Kiruna. The steel plates are exposed to a hostile environment with heat cycles and corrosive atmosphere. An evaluation of the plates was made in co-operation with LKAB Metlab in Luleå and LKAB mechanical workshop in Kiruna. Instruments used are stereomicroscope, LOM, SEM, Spectroscope, Vickers Hardness and a surface nish meter. Results show the protruding areas of the plates are exposed to a tribochemical wear, where tops of the rough areas are torn down. A coating test is carried out at Tribolab, LTU in Luleå, using an SRV. Samples with a wear and corrosion resistant coating called Diamalloy 4276 abrade against eachother at high temperature and pressure. The coating do help to resist wear, but the environment of the test is to unrealistic to say by certain that it will help in the grate. A FEM-model in COMSOL Multiphysics 4.4 is made to calculate thermal stresses between coating and metal, the result show stresses up to 1 GPa will occur, this can be explain by the big dierence in thermal expansion coefficients of the materials. It will probably create cracks in the coating surface. Two solutions are presented, a coating is not recommended. The tribochemical wear is decreased by using a better surface nish. Therefore one can either machine the areas by drilling or milling, or one can change the casting method. Today sand casting is used, by using shell casting or precision casting, for example Shaw process, the surface nish is better over the whole plate, which also is better for corrosion resistance since less initiation points exist. Denna rapport presenterar en undersökning av slitaget på sidorna av grateplattor som används i gratekilnprocessen i hematitpelletstillverkningen på LKAB i Kiruna, även lösningar presenteras. Plattorna benner sig i en svår miljö med termiska cykler och korrosiva substanser. Utvärderingen av slitaget gjordes i ... Bachelor Thesis Kiruna Royal Institute of Technology, Stockholm: KTHs Publication Database DiVA Kiruna |
institution |
Open Polar |
collection |
Royal Institute of Technology, Stockholm: KTHs Publication Database DiVA |
op_collection_id |
ftkthstockholm |
language |
English |
topic |
Grate plate wear Metallurgy and Metallic Materials Metallurgi och metalliska material |
spellingShingle |
Grate plate wear Metallurgy and Metallic Materials Metallurgi och metalliska material Martinsson, Johan Wear of Grate Plates |
topic_facet |
Grate plate wear Metallurgy and Metallic Materials Metallurgi och metalliska material |
description |
This report describe the wear of the protruding areas on the sides of the grate plates in the grate-kiln process in the hematite pellet production in LKAB, Kiruna. The steel plates are exposed to a hostile environment with heat cycles and corrosive atmosphere. An evaluation of the plates was made in co-operation with LKAB Metlab in Luleå and LKAB mechanical workshop in Kiruna. Instruments used are stereomicroscope, LOM, SEM, Spectroscope, Vickers Hardness and a surface nish meter. Results show the protruding areas of the plates are exposed to a tribochemical wear, where tops of the rough areas are torn down. A coating test is carried out at Tribolab, LTU in Luleå, using an SRV. Samples with a wear and corrosion resistant coating called Diamalloy 4276 abrade against eachother at high temperature and pressure. The coating do help to resist wear, but the environment of the test is to unrealistic to say by certain that it will help in the grate. A FEM-model in COMSOL Multiphysics 4.4 is made to calculate thermal stresses between coating and metal, the result show stresses up to 1 GPa will occur, this can be explain by the big dierence in thermal expansion coefficients of the materials. It will probably create cracks in the coating surface. Two solutions are presented, a coating is not recommended. The tribochemical wear is decreased by using a better surface nish. Therefore one can either machine the areas by drilling or milling, or one can change the casting method. Today sand casting is used, by using shell casting or precision casting, for example Shaw process, the surface nish is better over the whole plate, which also is better for corrosion resistance since less initiation points exist. Denna rapport presenterar en undersökning av slitaget på sidorna av grateplattor som används i gratekilnprocessen i hematitpelletstillverkningen på LKAB i Kiruna, även lösningar presenteras. Plattorna benner sig i en svår miljö med termiska cykler och korrosiva substanser. Utvärderingen av slitaget gjordes i ... |
format |
Bachelor Thesis |
author |
Martinsson, Johan |
author_facet |
Martinsson, Johan |
author_sort |
Martinsson, Johan |
title |
Wear of Grate Plates |
title_short |
Wear of Grate Plates |
title_full |
Wear of Grate Plates |
title_fullStr |
Wear of Grate Plates |
title_full_unstemmed |
Wear of Grate Plates |
title_sort |
wear of grate plates |
publisher |
KTH, Materialvetenskap |
publishDate |
2014 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160603 |
geographic |
Kiruna |
geographic_facet |
Kiruna |
genre |
Kiruna |
genre_facet |
Kiruna |
op_relation |
http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160603 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1802646537045540864 |