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Arbetet är ett examensarbete vid Karlstads Universitet och är den avslutande delen i programmet Högskoleingenjör i maskinteknik. Arbetet har utförts på uppdrag av Volvo Construction Equipment AB i Arvika under vårterminen 2021. Examensarbetet syftar till att undersöka och lösa ett problem med att lackskador uppstår på främre hyttfästet på bakramarna till hjullastarmodellerna L60H-L120H. Problemet har angripits med ingenjörsmässig metodik och har resulterat i en designändring på den befintliga fixturen som bakramen vilar i innan den lyfts över på banan. Designändringen har kompletterats med speglar som avser att assistera truckföraren när bakramen manövreras vid iläggning i fixturen. Designändringen modellerades i CAD-programmen PTC Creo och Catia. Den konstruerade designändringen består av två sammanfogade stöttor som håller upp bakramen under midjan i kombination med en uppstyvning av balkramverket som syftar till att hålla upp den nya fixturen säkert och stabilt. Konstruktionen har analyserats i PTC Creos inbyggda FEM-funktion, även kallat Pro Engineer. De högsta spänningarna som uppstår på fixturen uppgick till 3 MPa. De högsta spänningarna i Balkuppstyvningen uppgick till 20 MPa. Som komplement till FEM-analyserna har spänningsanalys med handberäkningar utförts på kritiska ingående delar. Den kritiska knäckkraften uppgick till 3190 kN. Konstruktionen är överdimensionerad för att säkerställa en säker konstruktion för operatörer som arbetar i och kring fixturen. Överdimensioneringen beror även på att fixturen främst konstruerats med tillgängliga material samtidigt som det ger ett enhetligt utseende i hela karusellfixturen eftersom de bakre fixturbenen använder samma dimensioner. Fixturen måste även klara av eventuella krängningar som uppstår då trucken eventuellt kör in emballaget som bakramarn kommer in på i fixturen. / The work is a thesis project at Karlstad University and is the final part of the Bachelor of Mechanical Engineering program. The work was carried out on behalf of Volvo Construction Equipment AB in Arvika during spring 2021. The degree project has aimed to investigate and solve a problem with paint damage occurring on the front cab bracket on the rear frames of the wheel loader models L60H-L120H. The problem has been tackled with engineering methodology and has resulted in a design change to the existing fixture in which the rear frame rests before it is lifted onto the production line. The design change has been supplemented with mirrors that are intended to assist the fork lift driver when the rear frame is operated when loading into the fixture. The design change was modeled in the CAD-programs PTC Creo and Catia. The engineered design change consists of two joined props that hold the rear frame below the waist in combination with a stiffening of the beam frame that aims to hold the new fixture securely and stably.  The design has been analyzed in PTC Creo’s built-in FEM function, also called Pro Engineer. The highest stresses that arose on the fixture amounted to 3 MPa. The highest stresses in the beam stiffening amounted to 20 MPa. As a complement to the FEM analyzes, stress analysis with manual calculations has been performed on critical components. The critical breaking force amounted to 3190 kN. The design is oversized to ensure a safe design for operators working in and around the fixture. The oversizing is also due to the fact that the fixture is mainly constructed with available materials at the same time as it gives a uniform appearance in the entire carousel fixture because the rear fixture legs use the same dimensions. The fixture must also be able to withstand any careenage that occurs if the fork lift unintentionally drives the packaging that the rear frame rests on into the fixture.

In this thesis stair climbing tools were made for manual wheelchairs. The tool is intended to be used primarily on entrance stairs. It can also be used as an evacuation aid for apartments/workplaces that do not have evacuation sites. At the present time there are only electric commercials aids which are expensive to own. The main problem of the work was to find a stair climbing mechanism. The design must be above all safe and cheap. The group used Fredy Olsson's method which consists of two phases namely principle and primary construction and other methods during work. A force analysis has been performed to confirm that the assistant’s pulling force is reduced during the stair climbing with the aid. The mechanics of material was analyzed with the help of Simsolid and then checked by hand calculations. The project team has at the end achieved a product that fulfills the most requirements that were set from the beginning.

This project has been carried out in collaboration with Getinge Storkök AB. The project aims either to further develop their current opening mechanism for their cooking pots or to develop a new one with the goal of making the opening of the pot lid easier. The design process used is developed by Fredy Olsson and the design steps that will be used are principle and primary construction which has helped the project team to develop a new opening mechanism that opens the pot lid with the push of a button. In order to ensure that the components that have been developed by the project team will meet the strength of the loads that arise, a design analysis has been carried out. To know that the finished components used for the opening mechanism have sufficient strength, the project team has checked through datasheets with specifications of maximum strength. The sum of the project has resulted in the development of a new opening mechanism that meets the purpose and objectives of the problem definition. Due to Covid-19, the project team did not have the opportunity to produce a finished prototype

Fordonstillverkaren Volvo Cars i Skövde vill undersöka vilken påverkan skruvförbandet mellan kamlagerhus och cylinderhuvud har på kamgångarnas rundhet. En förberedande genomgång av processflödet genomfördes där varje del isolerades och undersöktes för att identifiera potentiella felfaktorer. Efter diskussion med företaget och en utökning av litteraturstudien identifierades de felkällor, kopplade till skruvförbandet, som antogs ha störst påverkan på kamgångens rundhet. “Plasticering av kamgången under åtdragning” och “elastisk deformation som leder till orundhet vid återmontering efter bearbetning” var de felkällor som ansågs ha störst påverkan på rundheten och undersöktes vidare. Uppskattande beräkningar genomfördes på förenklade modeller av dessa felkällor för att identifiera sannolikheten för påverkan på kamgångens rundhet. Efter detta identifierades en modell för att uppskatta klämkraften som skruvförbandet utsätter komponenterna för. Klämkraften i förbandet mättes sedan och kombinerades med modellen för att få fram klämkraften i förbandet i det faktiska processflödet. Resultaten från mätningen användes i en digital FEA (Finita Element Analys) som tillsammans med de utförda beräkningarna ej visade på plasticering men stärkte sannolikheten att den elastiska deformation som sker inför bearbetningen skulle kunna bidra till den uppmätta orundheten. Vidare arbete kommer dock krävas för att säkerställa denna hypotes. / Vehicle manufacturer Volvo Cars in Skövde wants to investigate what effect the screw joint between cam bearing housing and cylinder head has on the roundness of the cam journal. A preparatory review of the process flow was conducted where each part was isolated and examined to identify potential failure factors. After discussion with the company and an extension of the literature study, the sources of error associated with the screw joint, which were assumed to have the greatest impact on the roundness of the cam journal, were identified. "Plastic deformation of the cam journal during tightening" and "elastic deformation leading to error in roundness during reassembly after machining" were the sources of error which were considered to have the greatest impact on the roundness and were investigated further. Estimating calculations were performed on simplified models of these sources of error to identify the probability of the influence on the roundness of the cam journal. After this, a model was identified to estimate the clamping force generated by the screw joint. The clamping force in the joint was then measured and combined with the model to obtain the clamping force in the joint in the actual process flow. The results of the measurement were used in a digital FEA (Finite Element Analysis) which, together with the calculations performed, did not show signs of plastic deformation but reinforced the probability that the elastic deformation that occurs prior to machining could be a contributing factor to the errors in roundness. However, further work will be required to validate this hypothesis.

Extrusion is a design process where the material is heated and pressed through a metal disc, called a die. The opening through which the material is pressed through forms the material. There are two different types of extrusion: direct and indirect extrusion. Where the difference between them is how the material is pressed through the die. In direct extrusion, the material is pressed against the die with a so-called stem and the material is extruded in the same direction as the pressing force. Indirect extrusion is carried out by pressing the die against the material, the material is extruded in the opposite direction to the compressive force. One wish from the University of Gävle is to extrude chips from chip cutting machining of low-carbon steel. A hydraulic press and dies are available at Högskolan i Gävle, but equipment for holding the die is missing. Therefore, Högskolan i Gävle wants a rig that holds the die and allows extrusion. The objective of the work is to contribute with theoretical design proposals of a rig that allows extrusion. The aim is to develop a theoretical design proposal on a rig that allows extrusion of metal chips.The development of the rig began with a literature study where the goal was to get an understanding of the key components in the extrusion process. Based on the literature study, a list of what functions the rig must have was developed. Afterwards requirements for the rig were developed based on physical limitations for the press to be used, conditions that makes the rig safe to use and functionally requirements. With brainstorming, suggestions were made to achieve the functions of the rig. Each suggestion was compared against the requirements and the suggestions that meet all the requirements were combined with each other to produce different concepts. Two concepts was selected for further development resulting in two different models for direct extrusion and two for indirect extrusion.The work has resulted in four different rigs: one rig for direct and one for indirect extrusion, where each extrusion method has a rig that is two-part and one rig that is solid (not two-part). Where the two-part variant can allow easier access to the extruded bar. In both direct and indirect extrusion, the die will lie on the rigs which are hollow and the extruded rod will be extruded under the die. The chips to be extruded will be pre-pressed in a canister that is of the same material as the chips. The chips will then be extruded together with the canister. Upon direct extrusion, the canister will be centered against the die with a container and the canister will be pressed against the die with a stem. In the case of indirect extrusion, the container will be lowered over the cansiter and the matrix to center them against each other. The container will then be used as a stem and press the canister against the die.

On behalf of Svalson AB, a requirement specification and a concept for a test rig that can be used for product tests of burglar-proof sliding windows are produced. The classification to be achieved is Resistance Class (RC) 3. According to the standard SS EN-1627 with associated sub-standards there are three relevant test methods to classify this sort of product. These refer to static loading, dynamic loading and manual burglary attempts. The test rig is manufactured in such a way that all tests can be performed on the same rig. It should also be capable of withstanding a load of 15 kN without deforming more than 5 mm. After setting up a plan for the project and gathering information, the project continues by developing different concepts of such a test rig. A requirement specification has been prepared in consultation with supervisor Johan Lyckestig and staff at Svalson as well as an external adviser at RISE. The concepts are weighted against this requirement specification and the concept with the highest score is optimized in terms of strength, weight and manufacturing cost. The concept that shows the most potential is made up of several modules that is mounted on a small, solid floor stand. The modules can be adjusted so that the frame holds objects of dimensions from 740 x 1020 to 1340 x 1870 mm. The optimization is done by analyzing the model with FEM in Solidworks and then modifying the areas that shows weaknesses or prove to be overdimensioned. After optimization, new analyzes show that the test rig meets the targets for maximum deformation at 15 kN load, while reducing the total weight by 158 kg. The final construction is estimated to weigh 283 kg. The analyzes should be taken as a clue and no exact reflection of reality. The actual possible deformation in subsequent product tests is difficult to predict, but everything indicates that the test rig should be able to withstand the stresses that it may be subject to in future product tests.

Displacement control of a pump means controlling the amount of fluid that is pumped per rotation. This is used to increase the efficiency or controlling the flow in a system and currently there is almost exclusively one type of displacement control available for piston machines on the market. With this method, the stroke length of the pistons can be varied by changing the angle of the so-called swashplate. There are however drawbacks with this principle that mainly concern in stability or efficiency. In this thesis, an unconventional approach to displacement control has been experimentally evaluated. The principle of this method is to vary the effective use of the stroke length by rotating the valve plate, which is a component that separates the inlet from the outlet. This can be done with an electric motor and the problems concerning efficiency and stability can be avoided. The main drawback with this type of control is however the high noise level caused by pressure ripple in the cylinders. This thesis treats the characteristics of this type of control, both theoretically and experimentally, and describes the analysed prototype. It also deals with new conceptual designs for this type of control. How-ever, in summary it can be said that the prototype behaved as expected but had problems with leakage.

ISO 14001 is an International Standard based on the concept that better environmental performancecan be achieved when environmental aspects are systematically identified and managed. Nowadays,manufacturing organizations are emphasizing more on product sustainability and the prevention ofenvironmental problems. Environmental aspect consideration opens an opportunity to enjoy theeffects of better environmental performances in terms of competitive advantage. The revised standardISO 14001:2015 was created by market requirements to get better environmental performance,ensuring top management involvement, a more specific life cycle analysis, better risk-based thinking,and a better communication strategy. The standard applies to any organization, regardless of size,type, and nature but does not specify environmental performance criteria or explicit rules concerningpreventive actions (Haggar et al., 2019) (ISO 14001, 2015). ISO 14001 (2015) emphasis more on theevaluation of risks and opportunities, also in reference to significant environmental aspects andcompliance obligations (Tüv Nord, 2015). The new ISO 14001:2015 certified organizations shoulddetermine the negative and positive environmental aspects while designing a product considering lifecycle thinking. Life cycle thinking could be a better approach to figure out more suitable solutionsfor sustainable development (Milazzo P. et al., 2017).This study has presented the output of an extensive literature review, survey results, and informationfrom the interview session to understand how the ISO 14001:2015 certified organizations areconsidering the environmental aspects in their life cycle thinking. The organizations monitoringstrategies and the risks and opportunities results from the implementation of ISO 14001:2015 (EMS)during the design and development phase are also analyzed. The study also prevails whether themanufacturing organizations consider design for environment (DFE) as a way of getting betterenvironmental performance by their products or not and how they are approaching towardssustainable development and circular economy. / <p>Final Report Submission date 28-05-2020</p>

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