This thesis was performed at Vendig AB which is a company that develops and sells products such as belt scrapers for conveyor. The thesis is divided into two parts, one part where it´s investigated which tension force is required to tighten Vendig AB´s scraper Hampus against the belt in a correct way. The second part is called mechanical design and here a new and more compact tension device is developed. Field studies has been conducted at a couple of Vendig AB´s costumers to get a knowledge base about how Vendig AB´s products are used, how they function and the environment they operate in. During one of the field studies the force between the scraper and the belt was measured. The result from the measurements, together with a report from LKAB [1], were evaluated and summarized in a table. The required force was recalculated for all different version of the scraper. After the tension force had been investigated the old tension device was evaluated and a requirement specification for a new was compiled in collaboration with Vendig AB´s group of technology. A number of concepts where then developed using the concept generator tool SCAMPER. One concept conformed very well to the requirement specification and was further developed. The concept was dimensioned by simulations in CAD, and basic drawings were made. The design solutions where discussed with suppliers and the design was updated. Finally a prototype was ordered to test and evaluate the concept. The tests revealed shortcomings in the prototype which has been evaluated and solutions has been discussed.