Well optimization in the petroleum industry is going to be an important challenge as the industry is more and more confronted with technical issues, for instance the production of unconventional reservoirs or deep wells, as well as for economic issues, due to the fast-moving oil and gas market. This master thesis is about the influence factor of pipe parameter on oil and gas operations and identifies possible cost saving potentials. Over the last years hardly any attention was paid on pressure behaviour as a consequence of the pipe wall roughness. Through the invention of coating and polishing methods the influence of pressure losses increases. Overall, this thesis is divided into two parts, a theoretical and a practical part. In the theory part different friction factors, depending on the fluid characteristics, are described and different roughness values for pipes are presented. Furthermore, special focus was paid on the pressure losses in the oil gas industry. Therefore, the most widely used approaches for pressure loss evaluation, during drilling, hydraulic stimulation and production of hydrocarbon, are described. In addition to the technical theory an economic part follows. To identify some savings due to pressure loss reduction, the whole operation economics for a hydraulic stimulation and production operation are shown. Therefore, typical methods for hydrocarbon forecasting are combined with the prediction of costs. The second part of this work deals with different scenarios to show the potential of pressure loss reduction due to the decrease of the absolute roughness. These scenarios restricted by a production operation and a hydraulic stimulation. Although a big potential for pressure loss reduction in the drilling operation exists, it is not of any interest for voestalpine Tubulars. Due to limited availability of data from the industry, these case studies are theoretical studies and the economic calculations were made through the usage of a risk software.