Nolato Gota AB is a company based in Götene. They manufacture plastic products for the automotiveindustry, such as battery boxes, covers and other panels. Volvo Cars AB is the largest customer andaccounts for approximately 70 % of all orders.The thesis was carried out in the department called the blue group. At Nolato Gota AB, there are severalmachine parks which produce plastic products by injection molding of thermoplastics. The bluegroup is one of the oldest departments in the company. The thesis has been carried out on machineswith a clamping force of over 500 tons.Nolato Gota AB is aware that their changeover process is often lengthy and varied, but there is currentlyno data to confirm this. The purpose of the thesis is to present improvement proposals on NolatoGota AB's changeover process through extensive data collection. Several production engineeringmethods and tools such as SMED, five why, time studies and work sampling will be used to generateimprovement proposals.The theoretical frame of reference has been used as a basis for choosing which production techniquesand tools to use during the thesis. Thanks to the literature study, it was possible to avoid problemsthat have arisen during other people’s work in similar areas.The empirical part of the work was carried out by using observations and interviews with changeoverstaff. A time study was performed according to the continuous method and, as a complement, worksampling was also conducted to identify the value-adding time. During the observations and the timestudies, it was clear that the lack of education had a significant impact on the changeover time.The results from the data collection showed that, on average, the changeover times are much longerthan Nolato Gota AB thought. All presented improvement proposals are linked to the collected data.By implementing the presented improvement proposals, the changeover time and variation may bereduced. The reason why no improvement proposals were implemented is that the time frame for thework is too small. Eliminating the wastes enables reducing the changeover time by up to 46 % and anadditional 23,6 % if the improvement proposals are implemented for a total reduction of 69,6 %. Forthe machines were the utilization warrants it the changeover time can be reduced to 74,1 % by the aidof an additional changeover worker. Nolato Gota AB has presented the cost for a machine downtimeto be 540 sek per hour for machines between 500- and 1000-tons clamping force. An optimizedchangeover will save Nolato Gota AB up to 1404 sek per changeover.