The invention discloses a technique of rotational molding equipment for coating of an inner wall of a pipe fitting. A plurality of regions of the outer wall of the pipe fitting are knocked in a coating process of the pipe fitting. The invention further provides a matched mechanism of the rotational molding equipment for coating of the inner wall of the pipe fitting. The matched mechanism comprises an electromagnetic attracting base, wherein the electromagnetic attracting base is attracted to the outer wall of the coated pipe fitting; and a knocking hammer which knocks the outer wall of the coated pipe fitting in a reciprocating manner and an action executing mechanism are arranged on the electromagnetic attracting base. The wall of the pipe fitting can be knocked by the electromagnetic attracting device, so that the local region of the wall of the pipe fitting is evenly and moderately shaken, powder accumulation is stopped effectively, and controllable degree of product quality is improved.