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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

From Diesel to Battery Power in Underground Mines : A Pilot Study of Diesel Free LHDs

Jäderblom, Niklas January 2017 (has links)
Load, haul and dump machines (LHDs) are commonly used in underground mines around the world. The machines are used to transport fragmented ore after blasting in the ore body. The main propellant used is diesel which accounts for a large part of the diesel consumed in mines today. This master thesis is a pilot study for further work to be done by LTU and Atlas Copco in a project called SIMS or Sustainable Intelligent Mining Systems, where the aim is to physically demonstrate diesel free LHDs doing productive work in mines. The objective of the thesis was to assess if the integration of battery-powered LHD machines is plausible in today’s underground mines. The aims were to map the current state of the production and to perform risk and job analysis of the new technology in the current systems. A theoretical framework was constructed with focus on safety, risk, hazards and change in work content. Social acceptance was then researched to be able to analyze how the new technology is received. Data gathering was done through interviews, observations, a focus group and reviewing documents while visiting Atlas Copco and two underground mines in Sweden. Diesel and electric-powered LHDs were studied in the mines and battery-powered LHDs were studied at Atlas Copco. The results present the current state of diesel, electric and battery-powered LHDs. How the machines are used in the visited mines and the identified risks with the work is presented along with the mapping of the battery system being developed by Atlas Copco. New risks that the battery system will bring to the work environment were identified using energy and deviation analyzes. The change in work content was discussed using the information from the visits and identifying what tasks will change, disappear and be added with the new technology. A large part of the thesis was analyzing the results with support from the theoretical framework. The analysis showed that a switch from diesel to battery-power would improve the overall health and safety inside the mines. A switch does not change the skill needed to operate the machines but can increase the qualifications for the service personnel. The main obstacles, in terms of social acceptance, with implementing the battery systems in the current state are that the need for constant battery exchange would cause problems in the production, the prejudice that the batteries would increase the consequences of a fire and the initial cost of making the switch. Recommendations for Atlas Copco going forward in the SIMS project were made. They need to emphasizing the safety of the technology to the users, developing the battery exchange so it can be done closer to the stopes and involve the operators in the projects of SIMS to help them understand the benefits it will have on them directly. / Gruvlastmaskiner (LHD) används ofta i gruvor runt om i världen. Maskinerna används för transportera fragmenterade malm efter malmen sprängts. Det huvudsakliga drivmedlet som används är diesel, som står för en stor del av den diesel som förbrukas i gruvor idag. Detta examensarbete är en pilotstudie för ytterligare arbete som ska utföras av LTU och Atlas Copco i ett projekt som heter SIMS eller Sustainable Intelligent Mining Systems. Syftet är att fysiskt demonstrera dieselfria LHD-maskiner göra produktivt arbete i gruvor. Syftet med examensarbetet var att bedöma om integrationen av batteridrivna LHD-maskiner är möjligt i dagens underjordiska gruvor. Målet var att kartlägga den aktuella produktionssituationen och att utföra risk- och arbetsanalyser av den nya tekniken i nuvarande system. En teoretisk referensram konstruerades med fokus på säkerhet, risk och förändring i arbetsinnehåll. Social acceptans undersöktes sedan för att kunna analysera hur den nya tekniken tas emot. Datainsamlingen gjordes genom intervjuer, observationer, en fokusgrupp och granskning av dokument givna vid besök på Atlas Copco och två underjordiska gruvor i Sverige. Diesel- och el-drivna maskiner studerades i gruvorna och batteridrivna studerades hos Atlas Copco. Resultaten presenterar det nuvarande läget för diesel, elektriska och batteridrivna LHDmaskiner. Hur maskinerna används i de besökta gruvorna och de identifierade riskerna med arbetet presenteras tillsammans med kartläggningen av batterisystemet som utvecklas av Atlas Copco. Nya risker med batterisystemet identifierades med hjälp av energi- och avvikelsesanalyser. Ändringarna i arbetsinnehåll diskuterades med hjälp av informationen från besöken och klargör vilka uppgifter som ska förändras, försvinnas och läggas till med den nya tekniken. En stor del av arbetet var att analysera resultaten med stöd från den teoretiska referensramen. Analysen visade att bytet från diesel till batterier skulle förbättra hälsan och säkerheten i gruvorna. Teknologibytet förändrar inte den färdighet som krävs för att kunna manövrera maskinerna men kan öka kvalifikationerna för servicepersonalen. De viktigaste hindren när det gäller social acceptans med att implementera batterisystemen i det nuvarande tillståndet är att behovet av konstant batteribyte skulle orsaka problem i produktionen, fördomarna om att batterierna skulle öka konsekvenserna av en brand och de initiala kostnaderna att göra ett byte. Rekommendationer för Atlas Copco för fortsatt arbete i SIMS-projektet gjordes. De behöver klargöra säkerheten hos den nya teknik för användarna, utveckla batteribytet så att det kan göras närmare produktionen och involvera operatörerna i SIMS-projekten för att hjälpa dem att förstå de fördelar som det kommer att ha på dem direkt.
32

CAN Tool for Atlas Copco’s Rig Control System / CAN-verktyg för Atlas Copcos riggkontrollsystem

Ljung, Marcus, Turner, Per January 2013 (has links)
The goal of this 15 hp thesis in computer engineering was to develop a tool for monitoring and analyzing the data flow on a Controller Area Network (CAN) called Rig Control System (RCS) that is used by Atlas Copco. Atlas Copco develops and manufactures machines for Mining and Rock Excavation. The Rocktec division is responsible for the Rig Control System platform used on machines in all division within the Mining and Rock Excavation Technique (MR) business area. The tool’s primary purpose is monitor and analyze data from the RCS network and present the analyzed data in an easy way to help with development and maintenance of RCS and machines that use RCS. The advantages and how data is sent over the CAN bus are presented as well as the CANopen protocol which is a higher layer protocol based on CAN. Two ways of data acquisition from RCS are presented, a simulated environment and real hardware. Different types of interprocess communication are presented as well as the pros and cons of each of these types. The creation of the tool required a Graphical User Interface (GUI) so different frameworks for this task are also presented and discussed. A version of the tool is presented and discussed in detail. The result of the project is a tool that with further development can be of great use to developers and service engineers working with RCS. / Målet med detta 15 hp examensarbete inom datateknik var att utveckla ett verktyg för att övervaka och analysera dataflödet på ett Controller Area Network (CAN) kallat Rig Control System (RCS) som används av Atlas Copco. Atlas Copco utvecklar och tillverkar maskiner för gruvdrift och bergbrytning. Rocktec-divisionen är ansvarig för Rig Control System-plattformen som används i maskiner från alla avdelningar inom affärsområdet Mining and Rock Excavation Technique (MR). Verktygets primära uppgift är att övervaka och analysera data från RCS-nätverket och presentera den analyserade datan på ett lättöverskådligt sätt för att vara till hjälp vid utveckling och underhåll av RCS och maskiner som använder RCS. Fördelar, hur data skickas över CAN-bussen och även CANopen-protokollet, som är ett högnivåprotokoll baserat på CAN, presenteras. Två olika sätt att samla in data från RCS presenteras, en simulerad miljö och riktig hårdvara. Olika typer av interprocesskommunikation och deras respektive fördelar och nackdelar presenteras. Skapandet av verktyget krävde ett grafiskt användargränssnitt så olika ramverk för denna uppgift presenteras och diskuteras i detalj. Resultatet av projektet är ett verktyg som med vidare utveckling kan vara till stor användning för utvecklare och servicetekniker som arbetar med RCS.
33

CORROSION-FATIGUE TESTING ON STEEL GRADES WITH DIFFERENT HEAT AND SURFACE TREATMENTS USED IN ROCK-DRILLING APPLICATIONS

Béjar, Luis Miguel January 2016 (has links)
Corrosion fatigue is a common failure mechanism in rock drilling components and many othermechanical parts subjected to cyclic loads in corrosive environments. A crucial part in the design ofsuch components resides in the selection of the right materials for the application, which ideallyinvolves testing and comparison of their performance under working conditions. The present work was performed with the purpose of designing a corrosion-fatigue testing methodthat would allow the designer to compare the performance of different materials exposed to corrosionfatigue, permitting also the comparison with results from dry fatigue testing. The method was designedfor rotating-bending machines. Two different steel grades were used during the work, one throughhardened and one case hardened. The effect of these heat treatments and of shot peening overcorrosion-fatigue behaviour were studied using the proposed method. It was proven that the testing speed has a strong impact on the fatigue life of steel. It was found that,at a fixed stress level, the case hardened and shot peened steel reached 3X10^6 cycles at 2300 rpm,while it failed at only 5X10^5 cycles with a testing speed of 500 rpm. A large beneficial influence of theshot peening was demonstrated. It was also observed that, at fixed testing speed, the shot peening onthe through hardened steel can increase its fatigue strength from 190 MPa to 600 MPa under corrosionfatigue. Many cracks were found at the surface of the shot peened parts, which are arrested near thesurface by the compressive stress layer from the shot peening. It was also found that, for the non-shotpeened parts, case hardening had a slightly higher corrosion-fatigue strength than the throughhardened. This might be a result of the compressive stresses from carburization, or due to the highercore toughness of this steel grade.
34

Future Assembly : AURES - The intelligent assisting arm / Framtidens montering

Ingvaldson, Anton January 2016 (has links)
The world is constantly changing and workers are forced to adapt to a pace that is more suitable for machines. In the Automotive Industry assembly line workers injuries keeps increasing despite major improvements in recent years. This is due to the cause that the marked demands more goods but to a lower cost. With this in mind, how can we create an aid for assembly line workers that could decrease repetitive strain injuries, facilitate flexibility and reduce the weight load on the workers joints? In this project I have explored the possibility to create new and intelligent aids for the assembly lines with great focus the human body and ergonomics.

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