Erosion is a common problem faced by oil and gas producers. The consequences of erosion may include unexpected equipment failure and thereby losses in production time and economy. Therefore it is necessary to study erosion under different flow regimes to provide protective guidelines to the oil and gas industry. This work discusses measuring erosion in a standard elbow in a 3-inch diameter pipe using an ultrasonic technique and a newly developed process algorithm. The ultrasonic transducers are permenantly mounted at 16 locations on the outside bend of the elbow which allows the measurement of erosion pattern under different operating conditions. Specifically erosion experiments have been conducted for single-phase (gas) and multiphase flow patterns (slug and mist flows) in the horizontal orientation. The experiments were performed with air and water as the fluids and using 150 and 300 micron particle sizes with 1 % concentration by weight. Results demonstrate the location of the maximum erosion on the elbow under considered flow patterns. Interestingly the location of maximum erosion for horizontal slug flow is on the top surface of the bend and for the other flow patterns the location of maximum erosion is on the outer radius of the bend near the 45 degree position. Keywords: Ultrasonic Technique Sand Erosion Single-Phase Flow Slug Flow