Two-phase liquid-liquid flow through pipelines is found in chemical, petroleum and petrochemical industries. Erosion-corrosion problems are the main reason of pipeline failure. Corrosion is caused by oxidation of the pipe wall while erosion is affected inertial impaction of the high velocity droplets or particles. The pipelines always contain fittings such as elbows, reducers and T-junctions. Erosion and corrosion rates are higher in fittings than in straight pipes due to the complex flow in fittings. This paper presents a liquid-liquid flow model. This will be incorporated with future work which is now in progress to calculate mass transfer of chemical species and to calculate corrosion rate. The liquid-liquid flow model was validated in the present study by using published experimental data.