Experimental investigation of the pressure drop for a gas-liquid two-phase flow system was conducted in an innovative device known as a coiled flow inverter (CFI). This configuration consists of helical coils with equispaced 90 degrees bends introduced at specific intervals in the coils. The idea is to create random mixing in a cross-sectional plane because of helical coils and complete flow inversion via the insertion of bends. The coils were prepared using a tube for which the following parameters were varied: internal diameter (0.005-0.015 m); curvature ratio, which is defined as coil diameter/tube diameter (6.7-20); pitch (1-2.5); and number of bends (1-15). The liquid flow rate was varied from 3.33 x 10(-6) m(3)/s to 1 x 10(-3) m(3)/s, and the gas flow rate was changed from 8.33 x 10(-5) m(3)/s to 1 x 10(-3) m(3)/s. Sixteen CFIs of different geometric configurations were tested. Comparison of the two-phase friction factor with that of different geometries, such as straight tube and straight helix for single-phase and two-phase systems, was made to account for the increment in pressure drop. It was observed that, because of the effect of secondary flow and flow inversion, the two-phase frictional pressure drop in these types of flow inverters is greater than that of a straight helix and straight tube, by a factor of similar to 2.5-3, respectively. The experimental data obtained for different CFI geometries were compared with the published works on helical coils. An empirical correlation for the two-phase friction factor in CFI was developed. The proposed correlation separately accounts for the effect of curvature ratio, number of bends, and gas and liquid flow rates, and it also retains the identity of each phase. The correlation was observed to fit the experimental data within +/- 15% and can also effectively predict the friction factor for the straight helix.