The goal of this paper was to describe and explain the concepts of viscosity, laminar and turbulent flow, as well as describe the physics of the boundary layer by means of which we learn the main data required for loss calculation in pipelines. In this paper, i have demonstrated and compare the results of calculations of line losses for a straight pipe 100 meters long and with a diameter of 5 centimeters, for four different temperatures (20, 40, 60 and 80 degrees Celsius) at three different flow regimes (Re 2300, 4000, 100000), for which it was necessary to determine speed limits. Friction factor was calculated using a Swamee-Jaine formula, as well as the Colebrooke formula that is calculated through an iterative procedure and presented in Excel. The obtained results claim that losses decrease as temperature rises. Likewise, line losses are calculated in the same pipe at a design speed od 2 𝑚 ∕ 𝑠, which results have demonstrated a slight loss decline of 0.33% at a temperature rise ranging between 20 and 80 degrees Celsius, which tells us it is an insignificant difference that can be disregarded in practice. Results at larger deviations are regulated by optimizing the remaining parameters such as speed, length, diameter, and roughness of pipes, while also maintaining the ratio of quality and price of the project.