In order to analyze the flow field distribution in the traditional 90° elbow and blind tee in the sand-laden flow environment, reveal the erosion mechanism, and compare and analyze the erosion resistance and wear reduction ability of the blind tee, this paper numerically simulate the flow field changes and wall erosion rates of the two pipe fittings with the same operating parameters, by using the RNG k-ε turbulence model, the DNV erosion prediction model and the particle-wall collision rebound model, based on the CFD-DPM method. The results show that:1)The erosion area of the 90° elbow is mainly distributed near the center line of the outer side wall of the elbow, and the main erosion areas of the blind tee are distributed at the outer arch of the "joint" and the end of the blind plug; 2)There is a flow vortex in the erosion path, which prevents the sand particles from directly colliding with the wall and slows down the erosion of the blind tee. With larger flow velocity, sand size, and mass flow rate of sand, the larger is the maximum erosion rate of both the 90° elbow and blind tee; but the blind tee exhibits more significant erosion resistance and wear reduction ability. The research results can provide theoretical guidance for safe operation of gas pipeline manifolds in gas gathering and transmission station.