A new type of flame cutting and online automatic slag cleaning system for continuous casting billets is a new technology of flame cutting for energy saving, emission reduction and consumption reduction. On-line automatic slag cleaning of continuous casting billets meets the requirements of steel rolling process and improves the yield of billet rolling. It is low input and high output, and the economic benefits are significantly improved. It fully implements automatic ignition, automatic fire breakage, cutting and ignition during cutting. The success rate is as high as 100%, the slit is small, energy is saved, economic benefits are improved, and carbon dioxide emissions are reduced by more than 50%. The purpose of energy saving and lowering is truly achieved, and the average gas consumption per ton of steel is about 1.5 yuan.