The application of paint in thermal spraying industry began at the beginning of the 20th century, and was first developed by Dr. M. u. scop of surrey, Switzerland in 1910. In 1912, wire flame spraying gun was developed successfully, and practical arc spraying gun was developed in 1916.

Paint wire flame spraying is still in use today.It USES oxyacetylene combustion as heat source and spraying material as wire.The nozzle siphons acetylene, oxygen and compressed air into the nozzle respectively, and the mixture of acetylene and oxygen produces a combustion flame at the nozzle outlet.The wire feeding wheel drives the wire rod to continuously send flame through the center of the nozzle. In the flame, it is heated and melted, and the compressed air forms a conical high-speed airflow through the air cap. The melted wire rod is atomized into fine particles.

Coating linear flame spraying coating structure for obvious laminar structure, coating has more pores and oxide slag, for zinc and aluminum coating, its porosity in 10%~15% in the spraying process, the flow rate and pressure of compressed air must be maintained constant, otherwise wire feeding fast or slow, will seriously affect the melting effect of wire.