Solid particle erosion has been a long-standing concern in oil-and-gas production and transportation systems, particularly in elbows of pipelines. Since it is difficult to exactly reproduce field conditions in the laboratory to study erosion, it is necessary to develop similarity criteria which ensure that lab results are representative of field conditions. Building on a previous work by the authors on similarity criteria that cover flow-field properties and particle-following behavior in gas and gas-mist flows, this work adds a similarity criterion for particle-rebounding and target material hardness. This new expanded set of criteria is validated using computational fluid dynamics by mapping five classic model tests to field cases—at different pipe diameters and pressures, with duplex stainless steel as the target material—and then comparing dimensionless maximum penetration rates and their angular locations. The analysis of errors demonstrates that the proposed criteria perform well in mapping laboratory data to field conditions.