Detta examensarbete har utförts åt Ålö, som är en tillverkare av frontlastare och redskap till dessa. Ett av deras redskap, vars syfte är snöröjning, är utrustat med hydrauliskt justerbara sidoklaffar som kan fällas bakåt och nyttjas som plogblad. De fyller dock inte denna uppgift tillfredsställande då snö tenderar falla tillbaka bakom dem. Det bildas även en triangulär spalt mellan klaffarna och underlaget vid plogning, detta lämnar kvar en sträng av snö, utöver det som faller ner bakom klaffarna. Målet i detta projekt var att utveckla en plogklaff som löser tidigare nämnda problem genom att ersätta den högra sidoklaffen till skopan. Utvecklingen har initierats med en studie av rapporter, existerande plogar, kontakt med brukare och fastställande av de begränsningar som råder. Detta har sedan utgjort grunden för en rad koncept, av vilka de mest lovande sammanfogades till en prototyp. Kraftberäkningar utifrån det lastfall som uppstår vid plogning har sedan använts för att bl.a. dimensionera skruvförband och skapa randvillkoren för en finita element-analys. Finita element-analysen har sedan nyttjats för att göra en uppskattning av antalet cykler med momentan maximal belastning plogklaffen klarar innan utmattningsbrott sker. Kraftberäkningarna visade att hydraulcylinderns tryckbegränsare öppnar redan innan maximal belastning uppnås. Finita element-analys och kraftberäkningar till skruvförband förutsätter likväl att maximal belastning kan erhållas momentant i syfte att ge konservativa resultat. Under denna förutsättning skiljer belastningen i skruvförbanden endast ca 7-10 % mellan finita element-analys och handberäkningar. Samtliga beräkningar är inom spannen för skruvförbandens hållfasthet. Utmattningsberäkningarna visade att antalet cykler plogklaffen klarar vid maximal belastning uppgår till ca 346 000. Detta avser områden av intresse och inkluderar således ej delar vilka redan utvärderats i originalklaffen. Svetsförband, som i regel är dimensionerande i situationer som dessa, har ej sett någon utmattningsmässig utvärdering utan kommer istället behandlas vid tester av prototypen. Prototypen uppfyller de utsatta målen och tillverkningsunderlag i form av 3D-CAD modeller och 2D-ritningar (inklusive svetsritningar) har levererats. En fysisk prototyp är även beställd och kommer tillverkas av Vännäs Verkstads AB, planerat leveransdatum är 2017-06-08. Den kommer utvärderas under vintern 2017/2018. / This thesis work has been carried out for Ålö, a manufacturer of front loaders and implements for these. One of their implements, whose purpose is snow clearing, is equipped with hydraulically adjustable flaps that can be folded backwards and used as plows. However, they do not fill this task satisfactorily as snow tends to fall down behind them. A triangular gap between the flaps and the ground is also formed during plowing. This leaves a string of snow behind, aside from the snowmass already falling down behind the flaps. The goal for this project was to develop a plow that solves the aforementioned problems by replacing the right side flap on the bucket. The development was initiated with a study of reports, existing plows, contact with users and determining existing constraints. This has since provided the basis for a series of concepts, of which the most promising ones were joined to a prototype. Force calculations based on the load scenario that occurs during plowing have been used to find appropriate fasteners and create boundary conditions for a finite element analysis. The finite element analysis has then been used to estimate the number of cycles with maximum load the plow can be subjected to before it succumbs to fatigue failure. Force calculations showed that the pressure limiter for the hydraulic cylinder opens even before maximum load is reached. Despite this, finite element analysis and force calculations for fasteners were still based on the condition that maximum load is achieved momentarily to produce convervative results. Under this condition, the load on fasteners differs only ca 7-10 % between finite element analysis and calculations made by hand. All calculations are within the span for the fasteners proof strength. Fatigue calculations showed that the number of cycles the plow can handle with maximum load amounts to approximately 346 000. This refers to areas of interest and thus does not include parts already evaluated in the original flap. Welds, which usually dictate minimum strength in situations like these, have not seen any fatigue evaluations, but will instead be addressed while testing the prototype. The prototype meets the set goals and production documentation in the form of 3D-CAD models and 2D drawings (including weldment drawings) have been delivered. A physical prototype is also ordered and will be manufactured by Vännäs Verkstads AB, scheduled delivery date is 2017-06-08. It will be evaluated during the winter of 2017/2018.

Bearing layers are used in road and building constructions as underlying soil layers to provide stability and support to the top layer that takes up the load. A normal bearing layer contains different amounts of materials such as stone, gravel, and filler. That mixture of materials contains a large amount of filler to give the product tightness and stability. Draining bearing layers usually contain less filler than ordinary bearing layers, because their purpose is to improve the drainage properties and reduce the risk of damage due to water collection.This thesis work took place at NCC's quarries in Sälgsjö and Hammarby. At NCC's rock quarry, there already is a standard bearing layer with a grain size of 0/32 and a filler content of approximately 4–5%. In this degree project, a production process has been created to obtain a drain bearing layer where the filler content is reduced to approximately 2–3%. The requirement for a draining carrier layer is 2–3% filler content and this requirement has been followed in this production process. The draining bearing layer has been produced based on a standard product with the same grain size.There are practical limitations in how the operations work and what capabilities are required. Moisture in the material has also been a limitation. In this project, work is done with freshly crushed material, which has a relatively low moisture content (1–2%). A vibration-free screen like the function of the harp has been designed and built. Then the standard product was run through the harp at different gradients and the new product was analyzed in the lab to see what filler content was achieved. A simulation test was performed using a FEM design program called Digiroad at Chalmers University of Technology in Gothenburg.The results demonstrate that the utilization of the developed models of harp screens reduces the proportion of filler in the material. Additionally, the conducted harp screen analyses confirm that the designed harp screens are effective in transforming a standard bearing layer into a draining bearing layer, which helps to prevent water accumulation under roads or buildings and thus reduces the risk of damage and problems. The efficient production process for producing draining bearing layers can be of great importance to ensure a sustainable and safe infrastructure.