Elbow as an integral part of natural gas piping systems, is vulnerable in erosive environments. This paper presents a computational fluid dynamics (CFD)-based erosion prediction model and its application to 3D double elbow. The salient features of this methodology include Eulerian continuous phase flow field generation through steady simulation using RNG turbulence model, and evaluation of particle distribution behaviour through discrete phase modelling using particle injection technique. Effects of gas velocity, sand mass flow, particle diameter, pipe diameter, elbow radius, angle of bend and bend orientation on the erosion rate in the double elbow are examined. The simulation results show that slow gas velocity, slow particle mass flow rate, small particle diameter, large pipe diameter, and high elbow radius bring about long service life for the double elbow.