Energy-saving hot air welding heater

The utility model discloses an energy-saving hot air welding heater comprising a heating drum and a handle, wherein the front end of the heating drum is provided with a hot air outlet and an inner cavity is internally provided with a heating coil; the handle is internally provided with a power wire and an air inlet pipe connected with the heating coil; the outer side of the heating drum is sheathed with an outer drum; and the air inlet pipe passes through a preheating cavity between the outer drum and the heating drum and an air inlet on the heating drum to be communicated with the inner cavity of the heating drum. In the structure, the heat-conducting gas entering from the air inlet pipe first enters the preheating cavity and then the inner cavity of the heating drum to be heated by the heating coil, and is finally ejected from the hot air outlet. The high temperature waste heat radiated from the outer wall of the heating drum is absorbed by heat transfer dielectric gas so that the heat-conducting gas is pre