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73 Uppsatser om Strip drain - Sida 1 av 5

Matarverk för Camcoil

By our employer Camatec Industriteknik AB have we been given the assignment to continue with the previous work ?Design of strip feeder?. Our goal with this work is to come up with a design basis for a strip feeder.Functionally a strip feeder consists of two rollers which with the aid of the friction between the strip and the coating on the roller create a strip force that pulls the strip through the working progress.Demands on this project:? 10 ? 600 mm in strip width and 0,1-1 mm in strip thickness.? Minimum 30m/min in production speed.? A maximum strip force on 30-40 kN.? The cost of the strip feeder?s components is to be considered of economy and quality.The need of a strip feeder occurs when the coil doesn?t manage to feed or pull the strip before or after a working process. The strip can otherwise be exposed by a permanent yield deformation or a change in the strip material if it?s pulled trough the working process only by the on ? and of-coils.

Produktivitet och kvalitet vid stickvägs- respektive beståndsgående förstagallring :

Nowadays the majority of the thinnings made in Swedish forests are done by machines, harvesters and forwarders. The most common model in thinning with a harvester is strip-road operated thinning and stand-operated thinning with one intermediate passage between the strip-roads. This study is a time study with some quality follow ups on a strip-road operated thinning model, a stand-operated thinning model with one intermediate passage between the strip-roads and a stand-operated thinning model with two intermediate passages between the strip-roads. The machines in the study were a small harvester (Forestline MPM C90) and a medium sized forwarder (Timberjack 1110). The study was made in Litsnäset outside the city of Östersund in Sweden and was made during the autumn 2007. In a lodgepole pine stand six study units (0,6 ha) were thinned with the three different models, two study units per model.

Valsningsteknik för extremt höghållfasta tunna stål

New high strength steels require improved cold rolling techniques. The aim of this degree project was to develop a new and money saving cold rolling technique to manufacture steel strip for saw blades. The work is based on earlier rolling experiments made with a high carbon steel grade at LuCoil Steel AB. The work also focused on the mill requirements to cold roll high strength steels. The results show that LuCoil?s existing cold rolling mill was actually designed for rolling low carbon steel.

Undersökning av steady state och utvärdering av valskraft och friktion vid kallvalsning av aluminium

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.

Stormskador i stickvägsgallrade bestånd i sydvästra Sverige :

A storm in January 2005 felled 75 millions cubic metres of forest in South Sweden. Previous studies of wind damage in thinned stands indicated the importance of early thinnings. The risks of wind throw increased by increasing age and height of the stands. Previous studies also indicated increasing risk of wind throw along the strip roads. The aim of the present study was to investigate wind damage in Norway spruce stands in South Sweden in relation to time of the first thinning and different pattern of strip roads (width, length and direction).

Dikesavståndets inverkan på såtid och skörd

All arable land in Sweden need a proper drainage for an effectively agriculture to take place. Of all arable land in Sweden, about 50% is naturally drained and 50% need artificial drainge. More than half of the tile drained area is in need of new drainage or renewed drainage. A good drainage improves farming and crop growth and increases the opportunity to achieve a high and safe harvest level. Future climate change and agriculture size rationalization will increase the need for good drainage. In this paper, two trials with three drainage distances, performed at Lanna experimental station, were analyzed using a mixed linear model.

Vindskador vid stickväg i 1:a och 2:a gallring i Boxholm, Östergötland : i stormen Pers fotspår

Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108 Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both spruce and pine stands and second thinnings only data from spruce stands was collected.

Värmeåtervinning ur spillvatten i befintliga flerbostadshus

Drain water heat recovery is an uncommon measure in multi-unit residential buildings. There istechnology available for the purpose but the knowing and experience of the heat recovery systems islittle. The purpose of this thesis is to evaluate the future potential of drain water heat recovery inmulti-unit residential buildings.A major part of the multi-unit residential buildings in Sweden were built during modernismen andrekordåren (1940?1975). Many of the buildings have worn out drain and water supply systems andmany are in need of a general refurbishment.

Öppen dagvattenhantering i urbana miljöer :

Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.

En jämförelse avseende beståndsgående-och stickvägsgående gallringsmaskiner

The purpose of this report is to investigate and compare the difference between stand-thinning machines and strip-road thinning machines, and how they affect the stand on behalf of future growth, theoretical economic result, wind impact, snow pressure and density of stand. The investigation is regarding the first commercial thinning of pine stands, after pre-commercial thinning that was well conducted. The investigation area was located near Katrineholm, Sweden. The measurements that were measured were strength of thinning and amounts of wind throws, snow-breaks and hauling damages. The results that emerged, was that thinning with strip-road machines had a significantly higher strength of thinning over all, as compared with the stand- thinning machines (45 percent versus 30 percent). Comparisons between wind-throws, snow-breaks and hauling damages of the stand could not establish any significant differences between the two methods that were investigated. Conclusions, over all, were that if forest owners want to have more timber volume left for second thinning and final cut of the stand, the forest owners should choose the method with stand-thinning machines. From the point of view of gentle treatment of the stand and ground damages the choice should be the same. However, the method with strip-road thinning machines is the most common and accessible method in Sweden. Most likely it is the most economical way to manage the stand for forest owners in present time. If the method with stand-thinning machines is becoming more common in Sweden, it is suggested for forest owners to consider the stand-thinning method as a candidate for treatment due to economic aspects..

Analys av linjetaxering i samband med gallringsinventering med avseende på kvalitet, tillförlitlighet och framtida utformning

Modern forest owners are very familiar with forest management and forest economics. Therefore they have high demands for quality in forest operations. Guarantee of quality in the shape of self-checking activities is an important tool to guarantee a well managed forestry operation. To meet the forest owners? demands on guarantee of quality and the entrepreneurs wish of an easy method for self-checking, the forest owners association, Södra skogsägarna, has developed a new method for thinning inventory. The purpose of this study is to evaluate the method that is used for self-checking and to find ways to develop and improve of the method. The data has been collected by inventory in a number of stands with circle-area survey and with strip survey, which is method that is used for self-checking. The results show that the strip survey does not diverge more than ±10 % in measuring values of basal area, number of stems, roads share, thinning quotient, outtake of basal area and total volume compared to circle-area survey.

Hur påverkas humankapitalet av migrationen mellan länderna i Nord? - En studien av fenomenen brain drain och brain gain i Ungern.

Brain drain innebär förlorat humankapital till följd av migration och förknippas oftast med högutbildade medborgares flytt till utlandet. Brain gain innebär å andra sidan ökat humankapital, antingen till följd av att migranter flyttar tillbaka till sina ursprungsländer eller genom ökade incitament för att utbilda sig på grund av migrationsmöjligheter. Syftet med uppsatsen var att undersöka hur den lagändring som trätt i kraft i Ungern, för att förhindra migration av välutbildad arbetskraft, påverkar humankapitalet i landet. Uppsatsen begränsades till att enbart innefatta läkare.För att genomföra undersökningen användes data från olika databaser samt andra forskningsrapporter och kompletterande källor. Materialet analyserades med hjälp av teorier kring löneutjämning samt neoklassisk teori rörande nyttomaximering och inkomstfördelning.

En analys av SCA Skog AB's metod för egenuppföljning av gallringar :

A high quality is highly requested in today?s thinnings, since these are the base for continued value development of the forests. Thinning quality often means a minimization of damages on soil, stems and roots during the cutting. One way to reach a high quality is to set up goals that will be followed up after the cutting is made. Self-checking gives information of the machine drivers work and guarantees the customers a good quality of work.

Konsekvenser av ny teknik på en sjukhusmottagning

An often encountered problem when implementing a mass flow regulator in a rolling mill is the one with measurement of speed. The most widely used solution is to fit a pulse counter to a wheel that is in contact with the strip. Common problems with this design are for instance scratch marks on the strip and problems with the flatness measuring system.  One way of circumventing the aforementioned problems would be a non-contact measuring system. The market of today only offers systems based on the Doppler principle.This report evaluates three different systems for non-contact speed measurement. Important areas in the evaluation have been the ability to operate under normal rolling conditions, integration in existing control system and how well the sensor can be fitted to the rolling mill.

Val av teknik för hastighetsmätning i kallvalsverk

An often encountered problem when implementing a mass flow regulator in a rolling mill is the one with measurement of speed. The most widely used solution is to fit a pulse counter to a wheel that is in contact with the strip. Common problems with this design are for instance scratch marks on the strip and problems with the flatness measuring system.  One way of circumventing the aforementioned problems would be a non-contact measuring system. The market of today only offers systems based on the Doppler principle.This report evaluates three different systems for non-contact speed measurement. Important areas in the evaluation have been the ability to operate under normal rolling conditions, integration in existing control system and how well the sensor can be fitted to the rolling mill.

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