The invention discloses a pawl component used for a pipe expander. The pawl component comprises a first pawl ring base, a plurality of reset springs and a plurality of expanding pawls; the pawl ring base comprises an annular ring base body; a plurality of pawl rotation round grooves and a plurality of torsion spring fixing round grooves are uniformly and circumferentially formed in the inner wallof the ring base body; a moving space used for moving of the expanding pawls is reserved between each pawl rotation round groove and the adjacent torsion spring fixing round groove; the spring body ofeach reset spring is arranged in the corresponding torsion spring fixing round groove; each expanding pawl comprises a pawl spindle; one end of each pawl spindle is provided with a wedged first driving convex block, and the other end is provided with a round-disc-shaped second driving convex block; the tail end of each first driving convex block is provided with a cylindrical convex block drivingshaft; and the outer wall of each first driving convex block is provided with a torsion spring clamping groove. The pipe expander is convenient to operate and can work without relying on electricity;and the pipe expander is applicable to pipe expanding work of copper pipes of different pipe diameters.