Spraying system in heading machine and heading machine

The utility model discloses an inner spraying system of a heading machine and the heading machine, the inner spraying system comprises a cutting head, a cutting arm, a cutting speed reducer, a connecting sleeve, a frame body, a cutting motor and a water inlet pipe mechanism, comprising a water inlet pipe group structure and a water conveying pipe group structure which are arranged from back to front along the central axis of the cutting part; the water inlet pipe group structure is connected with the tail end of the cutting motor, and a water inlet pipe of the water inlet pipe group structure penetrates through the cutting motor from back to front; the water conveying pipe group structure is connected with an input shaft of the cutting speed reducer, and the rear end of a water conveying pipe is detachably connected with a water inlet pipe; and the water conveying pipe is communicated with the hollow inner cavity of the main shaft of the cutting arm so as to convey water to the cutting head through the main s