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Navarro, J., Schunnesson, H., Ghosh, R., Segarra, P., Johansson, D. & Sanchidrián, J. Á. (2019). Application of drill-monitoring for chargeability assessment in sublevel caving. International Journal of Rock Mechanics And Mining Sciences, 119, 180-192
Open this publication in new window or tab >>Application of drill-monitoring for chargeability assessment in sublevel caving
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2019 (English)In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 119, p. 180-192Article in journal (Refereed) Published
Abstract [en]

Currently, the charging procedure for sublevel caving mining is carried out with no prior information of the rock mass condition. Thus, engineers are blindsided to unexpected rock conditions and ill-prepared to address issues associated with collapsing boreholes. This results on charging problems and, as consequence, bad fragmentation of the rock after blasting which difficult ore loading and transportation as the gravity flow of the rock is reduced.

This paper builds up the work done by Ghosh et al. (IJRMMS, 2018), to classify the geotechnical rock condition into five classes (solid rock, fractured rock, cave-in, minor and major cavity). From it, two applications based on the Measure While Drilling (MWD) technique have been developed: one for geotechnical rock condition of orebodies and the other for predicting the risk of collapse in boreholes. The work of Ghosh et al. has been improved into a geotechnical rock condition block model to simplify the quantitative assessment and automatic recognition of rock trends. A thorough correction of the MWD parameters has been also applied to minimize external influences other than the rock mass. From it, the risk of borehole collapses model has been developed by comparing different combinations of the geotechnical rock condition block-model with the charging length of 102 production fan-holes. The assessment of the number of collapsed and non-collapsed blastholes and the charging length/blasthole length ratio has been used to assign high, medium or low risk of collapse to each combination. The results predict collapses in the first half of the fan-holes for the high risk, collapses in the second half of the fan-hole for the medium risk and no collapses along the hole for the non-risk holes. The two models have been applied in large scale for two orebodies in the Malmberget mine, Sweden, which comprises 20 drifts and 5060 fan shape long-holes.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Rock mass condition, Underground blasting, Measurement while drilling (MWD), Block model, Explosives
National Category
Other Civil Engineering
Research subject
Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-74969 (URN)10.1016/j.ijrmms.2019.03.026 (DOI)000472023100018 ()2-s2.0-85065716586 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-06-25 (johcin)

Available from: 2019-06-25 Created: 2019-06-25 Last updated: 2019-07-10Bibliographically approved
Ghosh, R., Gustafson, A. & Schunnesson, H. (2018). Development of a geological model for chargeability assessment of borehole using drill monitoring technique. International Journal of Rock Mechanics And Mining Sciences, 109, 9-18
Open this publication in new window or tab >>Development of a geological model for chargeability assessment of borehole using drill monitoring technique
2018 (English)In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 109, p. 9-18Article in journal (Refereed) Published
Abstract [en]

In the mining industry, the ability to charge and blast a production borehole is fundamental. However, if rock mass conditions are challenging, with cavities, fracture zones or even unstable boreholes, the charging crew may fail to insert the required amount of explosives, resulting in bad fragmentation and significant production disturbances in the downstream process. Prior detailed knowledge of the chargeability of each production fan or ring will improve both the planning and execution of the charging work in a mine. The paper describes a study using the drill monitoring technique to assess the chargeability of production boreholes. For the study, data were collected on four drill parameters, penetration rate, rotation pressure, feed pressure and percussive pressure, from 23 drill fans with a total of 186 boreholes. A parameter called fracturing was calculated based on penetration rate variability and rotation pressure variability. Sixty-three boreholes were filmed to establish different rock mass conditions: solid rock, cavities, fractured zones and cave-ins. Principal Component Analysis (PCA) was performed to model the relationship between drill monitoring data and the geological features. The developed model shows high potential by identifying charging problems directly from drill monitoring data, and has been verified and validated in a real charging operation in an operating mine.

Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Other Civil Engineering
Research subject
Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-70266 (URN)10.1016/j.ijrmms.2018.06.015 (DOI)000440458000002 ()2-s2.0-85049528017 (Scopus ID)
Note

Validerad;2018;Nivå 2;2018-08-08 (andbra)

Available from: 2018-08-08 Created: 2018-08-08 Last updated: 2018-08-21Bibliographically approved
Ghosh, R. (2017). Assessment of rock mass quality and its effects on charge ability using drill monitoring technique. (Doctoral dissertation). Luleå: Luleå tekniska universitet
Open this publication in new window or tab >>Assessment of rock mass quality and its effects on charge ability using drill monitoring technique
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

For an efficient mining operation, it is essential to have as much information as possible aboutthe ore to be excavated and the rock masses surrounding the ore. Geological information andthe content and distribution of extractable minerals, are central concerns for long term mineplanning. However, for mine stability and production scheduling, the mechanical conditionsof ore and side rock are also very important. The underground mining process normallyconsists of a number of unit operations, such as drilling, charging, blasting, loading,transportation, hoisting etc., linked in a production chain. The quality of the initial operations(drilling, charging and blasting) normally defines the pre-conditions for the following loadingand transportation processes in the mine. The ability to fully charge holes as planned has beenidentified as one of the major obstacles for smooth fragmentation. Course or unevenfragmentation will, for example, significantly affect the loading and transportation efficiencyin the downstream production chain.Earlier studies in LKAB’s Malmberget mine have shown that the chargeability is on averagearound 90%. However, individual levels can have an average chargeability of only 70% andindividual rings, at those levels, can suffer from chargeability as low as 50%. A significantpart of these problems has its origin in geo-mechanical problems in the rock mass. Therefore,detailed knowledge of the rock mass condition surrounding the boreholes is essential toimprove the planning and execution of the charging works in a mine and to improve overallfragmentation and production efficiency.The focus of this thesis is therefore to define and evaluate geo-mechanical features in thedrilled rock mass effecting chargeability, and to evaluate drill monitoring technique for theassessment of rock mass quality and its effects on borehole’s chargeability using hydraulic In-The-Hole (ITH) percussive drilling.The research is based on literature review, drill-monitoring data, borehole filming, on-lineproduction database and monitoring of charging operation. Statistical methods are used toanalyse drill data. The data have been collected from LKAB’s underground mine inMalmberget, Sweden.Several rock mass conditions including caving, shearing, deformation, fracturing, cavities,solid rock, etc., have been identified during filming of 361 production boreholes.Measurement While Drilling (MWD) technique has been used to assess the quality of thepenetrated rock mass. In order to do so, a detailed analysis of the drilling system and thedrilling control including how monitored parameters relate to each other and to the penetratedrock mass conditions, has been performed. The results show that the MWD data containpronounced hole length dependent trends, both linear and step-wise linear, for mostparameters. By combining the borehole filming and the analyses of monitored drillparameters, the drilling responds to each geo-mechanical features in the rock mass is furtherdemonstrated. High correlation has been found between the geo-mechanical rock properties(fractures, cavities, solid rocks, etc.,), and the registered drilling system’s response. Theanalyses show that the responses from the drill monitoring system can distinguish between solid rock, fracture zone, cavity and cave-in. Based on the correlation between the registereddrilling system’s responses and the geo-mechanical features, a geo-mechanical model isdeveloped to assess the borehole chargeability. Principal Component Analysis (PCA) isperformed to model this relationship. The developed model can distinguish fans, or parts offans, with solid, non-fractured rocks where no chargeability problems can be expected, fromfans, or part of fans, with fractures, cavities or cave-in risks, where chargeability problemscan be expected. The model shows high potential for identifying charging problems in theborehole, and has been verified and validated by following an actual charging operation in thereal production environment.

Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2017. p. 70
Series
Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, ISSN 1402-1544
Keywords
Underground mining, Sublevel caving, Rock mass quality, Borehole filming, Borehole quality, Borehole stability, Borehole instability, Drill monitoring technique, Measurement While Drilling (MWD), Hydraulic in-the-hole (ITH) drilling, Drill system behaviour, Principal Component Analysis (PCA), Geo-mechanical model, Chargeability, Fracture zone, Shear zone, Cave-in, Cavity, Rock blasting
National Category
Mineral and Mine Engineering Geotechnical Engineering
Research subject
Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-65584 (URN)978-91-7583-963-9 (ISBN)978-91-7583-964-6 (ISBN)
Public defence
2017-11-08, F1031, Luleå University of Technology, Luleå, 10:00 (English)
Opponent
Supervisors
Available from: 2017-09-12 Created: 2017-09-11 Last updated: 2018-06-12Bibliographically approved
Ghosh, R., Danielsson, M., Gustafson, A., Falksund, H. & Schunnesson, H. (2017). Assessment of rock mass quality using drill monitoring technique of Hydraulic ITH drills (ed.). International Journal of Mining and Mineral Engineering, 8(3), 169-186
Open this publication in new window or tab >>Assessment of rock mass quality using drill monitoring technique of Hydraulic ITH drills
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2017 (English)In: International Journal of Mining and Mineral Engineering, ISSN 1754-890X, Vol. 8, no 3, p. 169-186Article in journal (Refereed) Published
Abstract [en]

A rock drilling system always responds to variations in the mechanical properties of the penetrated rock mass. Combining the drill response with a detailed understanding of the drill system has the potential to give a detailed and high-resolution characterisation of the penetrated rock mass along the borehole. This paper analyses 186 boreholes, drilled using a water powered in-the-hole (ITH) drilling technique considering drill parameters; penetration rate, rotation pressure, feed pressure and percussive pressure. In addition, it suggests, calculates and uses a parameter reflecting rock fracturing. Sixty-three of the holes were filmed with a borehole camera to reveal the geo-mechanical features. The results show that the responses from the drill monitoring system can distinguish between solid rock, fracture zones, cavities and damaged rock. The ability to extract this information directly from the drilling operation provides unique prior information and can be useful to adjust production planning before charging and blasting boreholes.

Place, publisher, year, edition, pages
InderScience Publishers, 2017
National Category
Other Civil Engineering
Research subject
Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-14546 (URN)10.1504/IJMME.2017.10006862 (DOI)2-s2.0-85027419669 (Scopus ID)deb3ea8d-3a3b-4f92-a89c-67863f4661bf (Local ID)deb3ea8d-3a3b-4f92-a89c-67863f4661bf (Archive number)deb3ea8d-3a3b-4f92-a89c-67863f4661bf (OAI)
Note

Validerad;2017;Nivå 1;2017-08-16 (rokbeg)

Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-11-20Bibliographically approved
Ghosh, R., Schunnesson, H. & Gustafson, A. (2017). Monitoring of Drill System Behavior for Water-Powered in-the-hole (ITH) drilling. Minerals, 7(7), Article ID 121.
Open this publication in new window or tab >>Monitoring of Drill System Behavior for Water-Powered in-the-hole (ITH) drilling
2017 (English)In: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 7, no 7, article id 121Article in journal (Refereed) Published
Abstract [en]

A detailed understanding of the drilling system and the drilling control is required to correctly interpret rock mass conditions based on monitored drilling data. This paper analyses data from hydraulic in-the-hole (ITH) drills used in LKAB’s Malmberget mine in Sweden. Drill parameters, including penetration rate, percussive pressure, feed pressure, and rotation pressure, are monitored in underground production holes. Calculated parameters, penetration rate variability, rotation pressure variability, and fracturing are included in the analysis to improve the opportunity to predict rock mass conditions. Principal component analysis (PCA) is used to address non-linearity and variable interactions. The results show that the data contain pronounced hole length-dependent trends, both linear and step-wise linear, for most parameters. It is also suggested that monitoring can be an efficient way to optimize target values for drill parameters, as demonstrated for feed force. Finally, principal component analysis can be used to transfer a number of drill parameters into single components with a more straightforward geomechanical meaning

Place, publisher, year, edition, pages
Basel: MDPI, 2017
National Category
Mineral and Mine Engineering Other Civil Engineering
Research subject
Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-63802 (URN)10.3390/min7070121 (DOI)000407363800015 ()2-s2.0-85026226267 (Scopus ID)
Note

Validerad; 2017; Nivå 2; 2017-08-15 (andbra)

Available from: 2017-06-08 Created: 2017-06-08 Last updated: 2018-11-26Bibliographically approved
Danielsson, M., Ghosh, R., Navarro Miguel, J., Johansson, D. & Schunnesson, H. (2017). Utilizing production data to predict operational disturbances in sublevel caving. In: Behzad Ghodrati, Uday Kumar, Håkan Schunnesson (Ed.), Mine Planning and Equipment Selection (MPES 2017): Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection Luleå, Sweden, August 29-31, 2017. Paper presented at 26th International Symposium on Mine Planning and Equipment Selection, Luleå, Sweden, August 29-31, 2017 (pp. 139-144). Luleå: Luleå tekniska universitet
Open this publication in new window or tab >>Utilizing production data to predict operational disturbances in sublevel caving
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2017 (English)In: Mine Planning and Equipment Selection (MPES 2017): Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection Luleå, Sweden, August 29-31, 2017 / [ed] Behzad Ghodrati, Uday Kumar, Håkan Schunnesson, Luleå: Luleå tekniska universitet, 2017, p. 139-144Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2017
National Category
Other Mechanical Engineering Mineral and Mine Engineering Other Civil Engineering
Research subject
Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-69084 (URN)978-91-7583-935-6 (ISBN)978-91-7583-936-3 (ISBN)
Conference
26th International Symposium on Mine Planning and Equipment Selection, Luleå, Sweden, August 29-31, 2017
Available from: 2018-06-04 Created: 2018-06-04 Last updated: 2018-06-12Bibliographically approved
Ghosh, R., Schunnesson, H. & Kumar, U. (2016). Evaluation of operating life length of rotary tricone bits using Measurement While Drilling data (ed.). Paper presented at . International Journal of Rock Mechanics And Mining Sciences, 83, 41-48
Open this publication in new window or tab >>Evaluation of operating life length of rotary tricone bits using Measurement While Drilling data
2016 (English)In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 83, p. 41-48Article in journal (Refereed) Published
National Category
Other Civil Engineering
Research subject
Operation and Maintenance; Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-5953 (URN)10.1016/j.ijrmms.2015.12.015 (DOI)000369609700004 ()2-s2.0-84952929316 (Scopus ID)424fe130-1dc5-42eb-90a1-8403f60d6249 (Local ID)424fe130-1dc5-42eb-90a1-8403f60d6249 (Archive number)424fe130-1dc5-42eb-90a1-8403f60d6249 (OAI)
Note
Validerad; 2016; Nivå 2; 20160108 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Ghosh, R., Zhang, Z. & Nyberg, U. (2015). Borehole instability in Malmberget Underground Mine (ed.). Paper presented at . Rock Mechanics and Rock Engineering, 48(4), 1731-1736
Open this publication in new window or tab >>Borehole instability in Malmberget Underground Mine
2015 (English)In: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453X, Vol. 48, no 4, p. 1731-1736Article in journal (Refereed) Published
National Category
Other Civil Engineering
Research subject
Operation and Maintenance; Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-6528 (URN)10.1007/s00603-014-0638-1 (DOI)000356884500030 ()2-s2.0-84933182948 (Scopus ID)4c09e7c7-19d4-4a51-85cb-e9eabc199620 (Local ID)4c09e7c7-19d4-4a51-85cb-e9eabc199620 (Archive number)4c09e7c7-19d4-4a51-85cb-e9eabc199620 (OAI)
Note
Validerad; 2015; Nivå 2; 20131230 (rajgho)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Ghosh, R. (2015). Rock Mass Characterisation Using Drill Performance Monitoring: Problems, Analysis challenges and Limitations (ed.). (Licentiate dissertation). Paper presented at . : Luleå tekniska universitet
Open this publication in new window or tab >>Rock Mass Characterisation Using Drill Performance Monitoring: Problems, Analysis challenges and Limitations
2015 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

In open pit mining, it is important to know as much information as possible about rock masses to be mined for more cost-effective mining operation. In rock engineering perspective, information about rock mass characteristics usually includes hardness of the rock, geological features, fractures, faults, ore contacts, water bearing stratum. The information about large scale rock mass characterisation is still based on traditional methods such as widely spacedcore drillings, geological mapping of exposed walls, analysis of drill cutting, etc but these methods involve uncertainty about rock mass characteristics in uncored areas. In addition, they are expensive and time consuming. The need for more inexpensive methods providing high resolution rock mass characterisation over large mining areas is therefore a priority forfuture mining industry. Measurement While Drilling (MWD) is a well-established drill monitoring technique which provides information about the rock mass in each production hole. This technique is inexpensive and also ensures high resolution information. By using this technique, drill parameters such as penetration rate, feed force, rotation speed, rotation torque and air pressure are recorded during production drilling which can be used to characterise the penetrated rock mass. However, recorded parameters are not only influencedby the variation of rock mass characteristics; they are also affected by the operators, rig control system interventions, bit wear and measurement errors. In order to use this large amount of data on recorded parameters for the purpose of rock mass characterisation, it is necessary to improve our existing understanding about the contribution of all the influencingfactors and to develop the techniques for identifying and minimising the effect of those factors on rock mass characterisation. The focus of this thesis is to evaluate Measurement While Drilling (MWD) system as a tool for large scale rock mass characterisation in rotary blast hole drilling. In this thesis, researchmethods mainly include literature review, data collection, processing, integration, and analysis. The data have been collected from one of the operating open pit mines in Sweden. Multivariate analysis has been performed to assess the wear of the bit. This thesis presents an attempt to evaluate recorded penetration rate and calculated specific energy for rock mass characterisation. Penetration rate is considered as resistance to crushingof the rock while the calculated specific energy is taken as an index of the mechanical efficiency of a rock working process. The analysis shows that horizontal maps of penetration rate and specific energy (hole average) value reflects the variation of rock mass characteristics in a bench. The areas in the bench which have comparatively higher penetration rate and lower specific energy reflect possible interaction between the bit and soft or weak rock orheavily jointed rock. In contrast some areas in the bench have a relatively lower penetration rate and higher specific energy, indicating possible interaction between the bit and hard rock. In addition, using penetration rate and specific energy values between two subsequent benches indicate similar boundaries among the penetrated zones. When plotting specific energy against penetration rate in each bench, a clear inverse non-linear relationship has beenfound between those parameters. This correlation indicates that penetration rate and specific energy can indicate rock mass behaviour. Further, statistical analysis is done to observe the statistical significance of penetration rate and specific energy values among the different penetrated areas in the bench. The results indicate that penetration rate and specific energy can be used for characterizing large scale rock masses. In addition, information about the rockmass in the upper bench can possibly be used in the next bench to improve production planning. However, hole by hole analysis shows penetration rate and specific energy are influenced by bit wear, hole depth variables, flushing system, operator influence, drill control system, etc.Principal Component Analysis (PCA) shows that penetration rate and specific energy reflecting the change of rock mass characteristics basically are not correlated to bit life length. The bit life length seems instead to be well correlated to the operational parameters such as rotation torque, rotation speed and to a minor extent feed force. Conclusions from PCA analysis must be conservative since the explanation rate for the first two components islimited to 56.5%. Further, the analysis shows that recorded penetration rate has a negative trend with the increasing hole depth. The calculated specific energy has a positive trend with the increasing hole depth. This means that recorded parameters are influenced by hole depth variables.The flushing system also influences recorded parameters. The analysis shows that constant air pressure from the collaring point to the end does not give a clear indication of better flushing system as frequent joints and regular water ingression usually cause fluctuation of pressure.Some of the above mentioned problems can be handled to minimise the effect of influencing factors on recorded parameters. The direct effect of bit wear and hole depth dependency can be minimised by generating a horizontal map of recorded data (e.g. penetration rate) over a large area in the bench. Hole depth dependency on recorded parameters can also be neutralised by performing normalisation based on a regression line using simple geometry. Inshort, the effect of influencing factors on the recorded parameters obtained by using the Measurement While Drilling technique can be minimised and, this technique, in turn, can become a useful tool for large scale rock mass characterisation.

Place, publisher, year, edition, pages
Luleå tekniska universitet, 2015. p. 106
Series
Licentiate thesis / Luleå University of Technology, ISSN 1402-1757
National Category
Other Civil Engineering
Research subject
Operation and Maintenance
Identifiers
urn:nbn:se:ltu:diva-26678 (URN)f7af7625-c601-4262-97e8-9cd1f6ebd5cf (Local ID)978-91-7583-334-7 (ISBN)978-91-7583-335-4 (ISBN)f7af7625-c601-4262-97e8-9cd1f6ebd5cf (Archive number)f7af7625-c601-4262-97e8-9cd1f6ebd5cf (OAI)
Note
Godkänd; 2015; 20150423 (rajgho); Nedanstående person kommer att hålla licentiatseminarium för avläggande av teknologie licentiatexamen. Namn: Rajib Ghosh Ämne: Drift och underhållsteknik/Operation and Maintenance Engineering Uppsats: Rock Mass Characterisation Using Drill Performance Monitoring Examinator: Håkan Schunnesson Institutionen för samhällsbyggnad och naturresurser Avdelning Geoteknologi Luleå tekniska universitet Diskutant: Professor Piyush Rai Indian Institute of Technology (BHU) Varanasi, Indien Tid: Tisdag 9 juni 2015 kl 10.00 Plats: F1031, Luleå tekniska universitetAvailable from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-06-12Bibliographically approved
Ghosh, R., Schunnesson, H. & Kumar, U. (2015). The use of specific energy in rotary drilling: the effect of operational parameters (ed.). Paper presented at International Symposium on the Application of Computers and Operations Research in the Mineral Industry : 23/05/2015 - 27/05/2015. Paper presented at International Symposium on the Application of Computers and Operations Research in the Mineral Industry : 23/05/2015 - 27/05/2015.
Open this publication in new window or tab >>The use of specific energy in rotary drilling: the effect of operational parameters
2015 (English)Conference paper, Oral presentation only (Refereed)
Abstract [en]

In rotary drilling, specific energy is considered to be an important parameter for defining mechanical efficiency of the rock destruction process. Specific Energy is defined as the energy required to remove one unit of rock. Specific energy is the function of the size of the borehole and various operational parameters including feed force, rotation speed, rotation torque and penetration rate. The harder the material, the higher the specific energy. The traditional method to calculate the specific energy is based on the parameters penetration rate, feed force, torque and rotation speed, that can be provided by Measurement While Drilling (MWD) data from the drill process. In this study, MWD data from an open pit mine in Sweden are used to evaluate data trends among logged parameters and calculated average specific energy. The results show that there is a significant hole length dependency for penetration rate and feed force that affects the predicted specific energy. This may be explained by that the hole cleaning efficiency is reduced with increasing hole length. The analysis shows that the specific energy is over-estimated by 45% in the bottom of an 18 m hole compared to the collaring point. The suggested solution is to use hole average or complement the specific energy calculation with a hole length related component.Keywords: Specific energy, Measurement While Drilling (MWD), Rotary drilling, Geo-mechanical response, Rock-destruction process

National Category
Other Civil Engineering
Research subject
Operation and Maintenance; Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-37495 (URN)b8aef0ed-ae1d-442c-8675-2525a351eb98 (Local ID)b8aef0ed-ae1d-442c-8675-2525a351eb98 (Archive number)b8aef0ed-ae1d-442c-8675-2525a351eb98 (OAI)
Conference
International Symposium on the Application of Computers and Operations Research in the Mineral Industry : 23/05/2015 - 27/05/2015
Note
Godkänd; 2015; 20150107 (rajgho)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2018-06-12Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-9108-9386

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