Composite tube manufacturing method and device

The invention discloses a composite tube manufacturing method and device. The method comprises the following steps: performing groove preparation on opposite edges of a composite board, and adopting an X-shaped composite groove, wherein a base groove is V-shaped, the composite groove is X-shaped; pre-determining optimal welding parameters through experiment, adopting high-frequency induction welding to complete the composite layer, removing induction welding external burrs after composite-layer welding, clearing the base-layer groove, adopting multi-wire submerged-arc welding on the base-layer welding, thereby accomplishing post-welding treatment such as thermal treatment after welding. The composite layer composite-layer welding adopts high-frequency induction welding, and metal filling is not needed, so that formation of impurities such as intermetallic compounds is effectively avoided, corrosion resistance of the composite layer is ensured, welding material cost is reduced; and the base-layer welding adopt