This report reflects an examination work performed for Getrag All Wheel Drive AB during the spring of 2005. Among the companies range of products there exists some concern regarding the amount of clamping force and Friction on bolted joints caused by the assembly torque.The aim of this project has been to determine if there is a simple way in which to identify and then practically apply testing methods for clamping force and Friction through utilization of existing testing equipment.Three separate methods of clamping force and Friction determination have been tested in rear drive unit, RDU, at a 30 Nm assembly torque. A fourth and final method, screw elongation with ultrasound, has been used as reference. The methods are:?Torque-Tension test.?Screw elongation with micrometer.?Joint stiffness test.?Screw elongation with ultra sound for reference.The results from tests can be viewed in table below.MethodTorque-TensionMicrometerCs=318 kN/mm Assembled with torque wrenchMicrometerCs=318 kN/mm Assembled on lineUltra-soundCS=311 kN/mm Ultra- soundCS=318 kN/mm Joint stiffnessTheoreticalClamping force-21,8 kN17,6 kN17,3 kN17,6 kN17,1 kN17,3 kNFriction-0,110,1470,1530,1470,1520,149.

The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry Friction, ice-debris or the difference in Friction on the left and right side of the stone. The side force comes from the fact that the Friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.

The thesis evaluates a new kind of bearing arrangement in a traction motor that ABB hasdeveloped. Since the arrangement is designed in a new and innovative way it needs to beevaluated to see if it is safe to use. In today?s traction motors, bearings with a big internalclearance (C4-clearance) are used. The basic idea of the new arrangement is to reduce the fitsbetween the bearing and shaft/house.

A new material model, for the FE-program ADINA, has been verified against twoexperiments. One unreinforced concrete beam and one reinforced concrete beam.The model, DF-concrete, has the possibility to estimate true concrete. However theresults indicate that in order to be sure that the estimations are true, there ought tobe data from the true concrete to verify against.Two FE-models have simulated the behavior of a ring-shaped part of the nuclearcontainment vessel. The results from the first, Frictionless, model agree with similarsimulations and hand calculations for high pressures in the containment vessel. Thesimulations of the nuclear containment vessel show cracking in the concrete after10-11 bars of over pressurization.

Floor surface in pig facilities can have an impact on animal welfare and pig health, as it can cause the pig physical damage and thereby increased risk of infectious diseases and lameness. The development of pig housing systems has resulted in a decreased use of bedding. It seems hard to find the optimal floor in farrowing pens, as it must suit both the sow and piglets. The floor Friction needs to be adequate to avoid slips and at the same time should the floor be non-abrasive. Abrasions and lesions caused by the floor are not only causing the animal suffering, but are also negative from an economical aspect.

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to Friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for Friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of Friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to Friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for Friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of Friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

During this master thesis, wear and Friction properties for the high-temperature alloy Kanthal APMT were studied. The results were also compared to 253MA. The initial tests showed, among other things, that the surface fineness of the muffle tubes matters in real applications like conveyor belts. A 253MA-sample wear-tested against a 253MA-tube showed lowest wear at 900°C while a pre-oxidized APMT-sample wear-tested against a APMT-tube had the lowest mean value of the Friction force at 1100°C, compared to all other tests..

Piled Friction soil show a set-up which is increasing with the time after installation. The cost could be reduced if the set-up had been taken into account when designing but in Sweden it is very unusual to do that. Previous studies showed that set-up can vary between 25 % and 75 % during the first 90 days after pile installation. This showed that the effect of the phenomenon is difficult to predict. A study involving five projects have been carried out by specifying certain parameters like pile type, method for pile installation and test method for measure the bearing capacity in Friction soils located in Sweden.

 AbstractThis Master?s thesis analyses the dynamics of the medieval counterweight lever engine, ortrebuchet, a type of mechanical artillery. The purpose is to study the differences between different types of these machines, and see if computer simulations can be used to validate preserved advice on construction. Simulations include machines with a fixed counterweight, a hinged counterweight and a combination of both counterweights.Due to the almost complete lack of archaeological finds and insufficient historical source material there are still, after more than a century of research, many unanswered questions concerning the design and performance of these machines.The present study is based on an analysis by Jahsman (2004). A more detailed mathematical model employing Coulomb-Friction is used.

The interaction between the driver, the car and the road is essential for the road safety. This case study focuses on the road condition and its effect regarding road safety issues. By studying and isolating the road condition aspect and its contributing role to the accident occurrence, the aim is to explore their relationship, as well as highlight the road parameters that are commonly associated with accident occurrence. This result will be used to develop and increase awareness of the impact of poor road alignment and poor road surface conditions on traffic safety, in order to prevent these accidents from occurring. The road parameters chosen for this study include side Friction, cross slope and rut bottom cross slope, road texture, curvature, drainage gradient and rutting.The case study was limited to lv 360 in Va?sterbotten, where all accidents with an unclear cause of the accident were studied, between 2003 and 2012 were carefully studied and assessed based on the condition of the road at the time of the accident.

The purpose with this thesis was to examine the cold rolling mill located at Högskolan Dalarna and to stabilize the rolling process, to achieve steady state. Experiments with cold rolling of an aluminium strip have given results for rolling force, Friction, reduction, strip tension and strain hardening. Results show that steady state has been found for the experiments with roll force and strain hardening, and not been found for the experiments with Friction and reduction. Results show that increased strip tension gives lower roll forces. The roll force equation of Stone shows comparable results with reality for dry contact with reductions up to 30 %, but starts being incomparable with higher reductions.

Formulation and testing of a new type of chainsaw lubricantThe company Agro Oil has come up with the idea of developing an environmentally adapted chainsaw lubricant with a new unusual base fluid. A field test with a tree-harvester shows unsatisfactory low temperature properties and high wear. In this work the viscosity, price and pour point of different combinations of the given base fluid and three other base fluids have been investigated. Desired viscosity and price are determined for different formulations. The new lubricants tested show lower pour points than almost all products on the Swedish market.A test equipment has been developed to investigate the wear.

The main purpose of this thesis has been to find a way to evaluate the soil parameters for the Total sounding method (TS), such as the inner Friction angles and settlement modules. This study only includes an analysis of soil profiles from the Stockholm region. The chosen location for the study is a proposed residential area east of Igelstaviken in Södertälje. Presently, the subject plot is located in a residential area and is also adjacent to a school area.Total sounding is originally a Norwegian soil testing method. The differences between the sounding methods (weight-, ram-, CPT-sounding) are for instance how the sound is driven into the ground and what kind of parameters that are registered.

The purpose of this study was to investigate how the social services and the police co-operate with each other when they come into contact with an individual within their realms of influence. It has been shown in a report by Fridolf (2008) that co-operation is not the aim itself but used as a mean to reach for better processes and better results. We have used qualitative interviews in the study, where three social workers and three policemen have participated from the same municipality to answer our questions. To analyze our result we have used system theory and organization theory. The result of our study shows that within this specific municipality the two agencies co-operate very well.