Sök:

Sökresultat:

30 Uppsatser om Crane - Sida 1 av 2

Gallring med vinkelkran : en jämförande studie av skördarkran med och utan horisontellt ledad vipparm

One of the most important components of a harvester is the Crane. Most harvester Cranes are only possible to pivot (or horizontally rotate) at the Crane pillar. Cranab in Vindeln, Sweden, has developed a new type of harvester Crane which has an extra pivot point on the outer boom. This makes it possible to reach around residual trees, easing thinning work in dense stands. The aim of the study was to analyze if the use of a pivoting outer boom (POB) Crane gave an increase in thinning production and if there were any differences in time consumption between the work elements for the POB Crane and a conventional Crane. A Valmet 911.3 equipped with a POB Crane was used in the study.

Skadeanalys och omkonstruktion av HMS Belos A-ram

In order to rescue a distressed submarine crew, the Swedish Navy is able to use a deep submergence rescue vehicle, DSRV. This mini submarine ascends, docks to the downed submarine and picks up the whole crew. The submarine rescue ship HMS Belos has a special Crane located in the aft of the ship to lift the surfaced DSRV aboard, which then docks on to the on board pressure chambers located below deck. During inspections the aforementioned Crane has shown to have problems with cracks in the structure, most of them located in the bolted joint between the top part of the Crane and the two leg parts. A simulation of the forces acting on the structure in heavy sea condition was conducted; these values were then used as input values in a Finite Element Method, FEM, analysis of the joint.

Jämförelse mellan BKR/BSK och Eurokoders behandling av utmattning i traversbalkar med tillhörande svetsfogar

This report has been performed for WSP Construction Design located at Arenavägen 7 in Stockholm. WSP Construction Design is one of the leading departments in Sweden in construction solutions regarding everything from building construction to industrial building. Great competencies regarding steel, wood and concrete constructions are available within the department which is well sought.Crane girders used in the industry are exposed to large loads that vary over time that includes instantaneous lifts and the Crane girders movement which lead to the phenomenon fatigue in the Crane girder and its ingoing welds. A control of fatigue needs to be performed after a certain lifespan measured in time which in turn is converted to a number of loadcycles. When the number of loadcycles amounts to a greater number the input welds resistance will have been reduced and the rate of utilization thereby increased.

Fundament för kompaktkran : En universell lösning

This thesis describes the universalization, improvement and further development of acompact Crane support frame for flatbed trucks. The work has been conducted at Eloch Fordonsteknik AB (henceforth EFAB) in Uppsala.The aim of the work has been to shorten the assembly time of the product. By doingso, the product can be kept on shelf, which in turn results in shorter lead time. Thishas been done by universalizing the support frame to be compatible with most of thechassis EFAB works with. Additionally, the entire construction has been made lighter,which will make it a more attractive choice for customers.A pre-study was conducted and information was gathered internally, as well asexternally, in order to ascertain that no limitation or possibility was overlookedduring the course of the project.One such limitation has been the geometry of the truck bed that the support frameshall be compatible with.

Prestation vid sönderdelning av GROT med olika typer av maskiner

There is a need for productivities data and data for different types of machines for comminution of logging residues. The lack of data and studies on GROT comminution makes it difficult to evaluate different chains for handling of residue fuels and make system analyses.Four types of machines with three different working principles were compared at six studies during winter conditions. Three to eleven trials during 9.5 to 30.7 minutes were made on each machine. Samples from the produced material at each study were sieved to determine the size distribution of the comminuted material. Samples were also taken from the studies for determination of moisture content.

Konstruktion av serviceutrustning till tunnelborrningsmaskin

The Master Thesis work this report is based upon has been conducted in cooperation with Svea Teknik AB. Svea Teknik is a consultant firm which is developing parts of a tunnel boring machine on behalf of Atlas Copco. The machine is being developed to mechanically excavate hard rock by fixating itself in the tunnel and then press a large rotating cutter-wheel equipped with disc-cutters against the tunnel wall. The disc-cutters are the tools that are in direct contact with the hard rock and are therefore exposed to extensive wear and needs to be replaced on a regular basis.The purpose of this Master Thesis has been to develop a service equipment that will enable time effective and safe changes of disc-cutters. The disc-cutters have a diameter of 17 inches and weigh about 130 kg.

Slöserijakt i betongdjungeln : En tidseffektivisering av monteringsprocessen inom stål- och betongprefab

The different aspects of each individual construction project such as the general conditions, design and economic restrictions as well as many more factors mean it is difficult to standardize building processes or plan in detail based on past experiences. As a result operational efficiency is often reduced, and unnecessary waste is generated. To make an organization more efficient and therefore reduce waste production everybody involved needs to appreciate and understand the improvements that can increase the organization?s efficiency. To investigate these improvements a time study was performed on two different construction sites, both of which involved buildings being constructed of prefabricated steel and concrete elements.

Utredning av energieffektiviseringspotential i ett flerbostadshus : Avseende på injustering av värmedistributionssystemet och installation av värmepump

The different aspects of each individual construction project such as the general conditions, design and economic restrictions as well as many more factors mean it is difficult to standardize building processes or plan in detail based on past experiences. As a result operational efficiency is often reduced, and unnecessary waste is generated. To make an organization more efficient and therefore reduce waste production everybody involved needs to appreciate and understand the improvements that can increase the organization?s efficiency. To investigate these improvements a time study was performed on two different construction sites, both of which involved buildings being constructed of prefabricated steel and concrete elements.

Dimensionering av Traverskranbana

Kranlaster som verkar på kranbanor varierar med tiden och kan inte behandlas som statiska laster, detta gör att en statisk beräkning inte är tillräckligt säker, därför bör kranbalkar utformas på så sett att den klarar av statiska såväl som dynamiska kranlaster.Arbetet valdes efter förstudier som gjordes på internet för att få grundläggande kunskap om ämnet. Informationen söktes på svenska, engelska och tyska för att kunna hitta relevanta och pålitliga källor som behandlar traverskranbanor enligt eurokod. Tack vare råd från Björn Åsted från Stålbyggnadsinstitutet (SBI), kunde en bok på tyska hittas. För att kunna jämföra resultaten används ett svenskt program CraneGirder EC3 under arbetet.Rapporten innehåller en beräkningsmodell för en valsad profil balk, beräkningar baserades på eurokod ekvationer och föreskrifter vilket var som dimensionerings underlag för arbetet. I denna rapport hänvisas hur en kranbana skall dimensioneras med hög utnyttjandegrad, ett antal kontroller gjordes för att säkerställa att balken och dess detaljer, såsom räl och svets är säkert utformade mot utmattning och deformation.

Produktivitet vid selektiv mekaniserad bioenergiröjning av eftersatta röjningsbestånd :

In Sweden, harvesting pre-commercial thinning (PCT) stems for energy purposes is a interesting way of financing the high cost of preparing dense stands for a profitable first conventional thinning. This concept can be labelled bioenergy thinning. The aim of this study was to quantify the productivity of a Vimek 404R light harvester with an accumulating Naarva-Grip cutting head during the bioenergy thinning of a self-regenerated stand west of Sunnansjö in Dalarna. The stand was birch-dominated, contained 15 371 stems/ha, and measured on average 4,6 cm Dbh and 7 m tall. Even though the driver was well experienced with the machine, the stand in question was the first one that he ever thinned in this manner. Nevertheless, the driver strived to accumulate as many stems as possible during each Crane cycle and chose to cut taller stems in half so as to make the handling and forwarding of the harvested stems easier.

Batterilyft för telekom basstationer

The purpose with this thesis work was to design and build a technical aid for installingbatteries in telecom base stations. Today that job is done manually, since there is noequipment on the market for that purpose. Installing batteries in base stations manually isa very tough job.To get ideas for possible solutions a preliminary study on existing lift aids was done.From the preliminary study the conclusion that some kind of overhead Crane would besuitable for the task was drawn. After that a lift for installing batteries in base stationswas designed, built and tested. The tests show that it is possible to minimize heavy liftingwhen installing batteries in telecom base stations, at a relatively low cost.ii.

Tillverkarnas syn på utvecklingen av väderskydd

How does the weather protection systems look like today, and how will they be developed in the future? These are questions that we have worked with during this project. At the start of our report there?s a summary of the leading weather protection manufacturers in Sweden. We have explained how these systems are constructed and how they work.

En jämförande studie av fem lastbilsmonterade flishuggar

The study was carried out as a time study of five wood chippers placed on trucks,so?called huggbilar. They are trucks with built?in wood chipper, chip bowl and Crane pulling a chip trailer. The system is used for chipping wood fuel, transporting, and delivering the chips to heating plants.

Halvautomatisk styrning av järnvägskran

En RMRC, Rail Mounted Railway Crane, är en kran för hantering av containertrafik till och från järnvägsvagnar. Kranen som är helt manuellt styrd utrustas med en semiautomatik som hjälper operatören att positionera kranen. Målpositionen för containern kommer från terminalens logistiksystem. För positioneringen har en lämplig regulator tagits fram som tar hänsyn till den mekaniska påverkan på motorer och växellådor som finns vid acceleration och retardation. Regulatorn har tagits fram och testats i en simuleringsmiljö.

Konstruktion av mutterdragare för stora moment

This degree project was conducted in collaboration with Gremo AB located in Ätran.The aim of the project was to develop a solution to secure quality and to help assemblingthe locknut holding the vertical hinge on the harvesters and foresters from Gremo.At this time the nut is assembled manually by the aid of an overhead Crane. The nut istightened differently from time to time, and there was no specified torque to which it istightened. Another present problem was the locking washer which sometimes getsdamaged during assembly, when this happens the procedure has to be started over fromthe beginning. The current assembly procedure is very time consuming and lengthy forthe employees.Our task was to design a machine that could tighten the nut to a specified torque with amargin of error of ± 3%. The assembly procedure will be held simple and the timerequired at a minimum.The project started by developing several principle solutions, the one solution that bestmatched our specifications were developed to a primary solution.Today we have started manufacturing and assembling our prototype.

1 Nästa sida ->