Hägglunds Drives in Mellansel, Sweden, manufacture radial piston hydraulic motors foremostwithin applications in the industry. These motors have several sliding contacts, one of these, isthe contact between piston ring and Cylinder bore. The radial piston hydraulic motors advantageis to produce high torque in very low rotation velocity, this result in that the maximum slidingvelocity between piston ring and Cylinder bore, during the whole stroke, is very low. Theconsequence of this low sliding velocity is that the contact between piston ring and Cylinderbore, during the whole stroke, is bound to the boundary lubrication regime. This result in, thatthe piston ring is exposed to wear, thus affect the service life of the complete hydraulic motor.To minimize wear of piston ring, it is essential to determine the oil film thickness between thepiston ring and Cylinder bore.

The exhaust arrangement on a Scania V8 consists of one manifold at each bank connected to a twin entry turbine (8-2-2). A study in GT-Power has shown improved performance and reduced Cylinder to Cylinder variations using two manifolds at each bank in combination with a single entry turbine (8-4-1). This thesis work analyses the difference in performance shown in simulation and verify it by engine test.The initial work was focused on simulation in GT-Power. Investigating how exhaust manifold volume and pulses effects the turbine efficiency and the mean effective pressure during the gas exchange. To verify GT-Power simulations four engine tests with different exhaust arrangement have been made.The results from GT-Power simulation indicate that a larger exhaust volume improve the turbine efficiency.

This Master Thesis is a product development project that has been carried out in cooperation with Scania CV AB. The purpose has been to find the relationship between geometric parameters and the swirl number for an XPI- Cylinder head in order to improve the design specification.The increased focus on environmental issues from society leads to tighter emission legislations for the truck manufactures. In order to drive the development forward considerable resources are spent on research and development on diesel engines and its combustion process. The inlet air has a significant impact on the formation of emissions and the flow that is desired is called swirl. Swirl is achieved by making the air rotate around the vertical axis of the Cylinder.Earlier Cylinder heads that has been developed at Scania CV AB have shown clear relationships between geometric parameters of the Cylinder head and the swirl number.

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.

Business unit Cylinder at ASSA AB in Eskilstuna are having problem with frictions in their production process. Changes are occurring and older products along with machineries are phased out and transferred to low-cost countries. This opens up possibilities to at a larger extend customize physical flows after production flows. The authors where given the task to analyze the production and find problem areas to improve and to give suggestion on how Business unit Cylinder can work to optimize their production flow.The aim of the thesis work is to come up with suggestions on how to reduce the lead time in production and how the tied up capital can be reduced. In more detail the task included to find problem areas that are counteracting an effective flow, give solutions on new flows for the production of the Cylinder core, give suggestions for new stock points for the production and how the production shall be managed and controlled.During the last twelve months ASSA AB has sold over 700 different types of Cylinder cores, and the product range is very wide.

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.

Want to help making the world a better place? Do it with HypOCycle!HypOCycle is a bachelor thesis that started in September 2007. The project is owned byLars-Johan Hjertz and Erik Westerlund.HypOCycle is probably the only bike in the world that has a linear pedal movement. Themovement comes from a new engine technique that hasn?t even been brought to themarket yet.

 This study was conducted in autumn 2008 on the Company AB, which is currently in a growth phase. The company manufactures hydraulic systems for the heavy vehicle industry and has annual sales of approximately 250 MSEK with 165 employees.The rapid growth and unchanged planning is the starting point for this report. It all began in 2005 when the company received an unusually large order. During this period, the first priority was to satisfy customers and all other focus was disregarded. This has primarily resulted in a messy production and long throughput times.

ÅF Test Center in Borlänge had a need to expand their capacity for compressive and tensile strength tests. They wanted to do this by using a hydraulic Cylinder, which they already possessed, to apply the force with. This required a load receiving structure. The aim of this work was to design and dimensioning a test bench for a Cylinder marked NIKE 300 tons. The work would result in a completed design proposal on a test bench which could manage to run the compressive and tensile strength tests of up to 3000 kN.

This thesis deals with the numerical 3D simulation of a four stroke, spark-ignited, internalcombustion engine, which is mounted on a high performance motorcycle. The work, carried outin collaboration with Politecnico di Milano and MV Agusta, focuses on the simulation of theintake, compression and expansion stroke, including combustion simulation, using an opensource CFD code.Simulation of internal combustion engines offers a great challenge in the field of CFD research.Moving boundaries of the solution domain, caused by the motion of the piston and valves, leadsto deformation of the computational grid, with decreasing quality of the solution as result. Basedon this, a previously developed mesh motion strategy was employed where a number of meshesare used to cover the whole simulation cycle. Within each mesh interval the internal cell pointsof the mesh are moved to account for the boundary motion of the piston and valves. This strategywas previously applied to simplified geometries as well as real engine geometries.

Test bench for air bearingsThis thesis work consisted of bringing forward and defining the test parameters relevant for a test bench and constructing a test bench that can test and verify the largest existing air bearings that are of use in Micronic Laser Systems AB machines. Because the knowledge about air bearings is limited it is thought that with the help of the test bench the knowledge would increase and in that way improve the air bearings.After learning more about air bearings and their purpose at Micronic Laser Systems AB, I started the concept phase for the test bench. For each part in the test bench I consulted my two tutors, Torbjörn Hedevärn and Johan Bergqvist, at Micronic Laser Systems AB. The final concepts where documented as 3D-modells in Solidworks and some of them have been tested in Solidworks FEM-program.The test bench is designed so that, with the help of a pneumatic Cylinder, 25 kilo weights are placed on the air bearing to test its stiffness, damping and the pressure performance under its surface area. To test these parameters the test bench has to have a pressure meter, accelerometer and a microcator.

Syftet med denna studie var att kontrollera om och i så fall hur mycketvisus förbättras med toriska linser jämfört med sfäriska linser vid astigmatism -0,50 D - -1,00 D.I studien ingick tolv försökspersoner, fördelat på nio kvinnor och tre män, medCylinder mellan -0,50 D och -1,00 D på ett eller båda ögonen korrigerades först medAir Optix® (sfärisk) beräknad på sfärisk ekvivalent och sedan med Air Optix forAstigmatism®(torisk) med styrkor baserade på refraktionen. Högkontrastvisus ochlågkontrastvisus mättes både monokulärt och binokulärt.I studien framkom att i både monokulärt och binokulärt finns en statistisktsignifikant förbättring med den toriska linsen jämfört med den sfäriska. Ävenlågkontrastvisus visar en förbättring både monokulärt och binokulärt med den toriskalinsen, denna skillnad är inte statistiskt signifikant. Även vid 0,50 D Cylinder finnsäven här en förbättring med den toriska linsen men denna är inte heller statistisktsignifikant, varken för hög eller lågkontrastvisus. För 1,00 D Cylinder är förbättringensignifikant vid högkontrast men inte vid lågkontrastS.

Projektet genomfördes på Ingenjörsfirma Edman & Sjöberg AB i Filipstad. Syftet med projektet var dels att utreda möjligheterna med att använda sig av vattenhydraulik, men även presentera nytänkande lösningar för ingående detaljer av en hydraulCylinder. Kvaerner Pulping AB, som var kund, efterfrågade en enklare Cylinder som fortfarande klarade kraven till låg kostnad. Önskemålet om nytänkande lösningar rörde främst hur kolvstången kan hållas ren från avlagringar samt att lösa genomströmningen i toppläget av rörelsen. Arbetet skulle mynna ut i ritningsunderlag för att senare generera en prototyp av Cylindern.

Utvecklingsavdelningen för hydraulcylindrar på Bosch Rexroth AB har identifierat ett marknadssegment för en lågprisCylinder som kan arbeta med högt tryck. Företaget har idag en lågprisCylinder på marknaden och vill vidareutveckla denna för att klara högre tryck. Detta examensarbete har utförts som en förstudie med syftet att presentera olika konstruktionslösningar av nuvarande Cylinders ingående delar, för att erhålla de önskade egenskaperna. Arbetet började med att ingående bryta ner den nuvarande Cylindern i mindre delar för analys. Det gjordes även en studie av konkurrenterna och vad deras sortiment har att erbjuda.

Our employer Camatec Industriteknik AB gave us the assignments to increase theirs range of versions on Camcoil that is their own patent product. Camcoil is a capstan system that is used when steel band fabricated. Exist for example in production lines their steel band should be annealed. Our goal with this work is to come up with a completed production basis on a Camcoil for heavy industry. The basis should contain calculations, 3D-constructions, drawings and cost proposal on manufacturing and detail purchase.Demands on this project:1.