The work aims to increase wear resistance of flap tubing anchor pieces in screw pump tubing string, improve efficiency of oil production and reduce operation cost. An Fe-based alloy layer was prepared on 45# steel substrate by adopting flame spray welding technology. Hardness, microstructure and wear resistance of the coating were investigated by scanning electron microscope, X-ray diffractometer, hardness tester and reciprocating friction testing machine. Contrast test and economical analysis of friction coefficient and wear loss were done between cutting edge welding-on materials of flap tubing anchor pieces and the alloy layer. The Fe-based alloy layer and substrate realized metallurgical bonding. The microstructure of the alloy layer was mainly composed of primary carbides Cr2C3 and Cr7C3, borides Fe2B, Cr2B and CrB, as well as eutectic substrates γ-Fe (Ni,Cr,C,Si), α-Fe, Fe3C, (Fe,Cr)7C3, Fe23(B,C)6 and Cr23C6. Average surface hardness of the alloy layer was 64.7HRC, almost 50% higher than that of the welding-on materials. Friction coefficient of the alloy layer stayed at 0.6, nearly 17% lower than that of the welding-on materials. After wear weight loss experiment, wear weight loss of the alloy layer was about 2/3 of that of the welding-on materials. The economical analysis showed that: cost of this strengthening process was about RMB 6.8305 yuan, nearly the same as that of the welding-on materials. After welding Fe-based alloy layer, hardness and wear resistance of the flap tubing anchor pieces are increased significantly and the service life is extended effectively. This study provides a reliable basis for wear-resisting strengthening and repair of the flap tubing anchor pieces, and also theoretical and practical basis for surface strengthening of the other quick-wearing parts in the oil production technology.