On-line automatic blanking method for metal pipes

The invention discloses an on-line automatic blanking method for metal pipes, and relates to an on-line automatic blanking method, in particular to the on-line automatic blanking method for the metal pipes. The problems that the automation degree of online saw cutting of metal pipes rolled by a pipe mill is low, the labor intensity of operators is high, and the production benefit is greatly limited are solved. The on-line automatic blanking method comprises the following specific steps that firstly, after a pipe rolled by an automatic pipe mill reaches a fixed-length sawing signal switch, a chipless rotary cutter is started, and the pipe is sawed; secondly, the sawn fixed-length pipe is conveyed through a conveying roller way, and when the head of the pipe passes through a detection switch of the conveying roller way, a material shifting device acts to shift the pipe to a material storage area; and thirdly, during rolling in the pipe inserting state, when the tail end of the pipe does not leave a rolling hole