Energy-saving rotary kiln with preheating device

The utility model relates to the technical field of rotary kilns, in particular to an energy-saving rotary kiln with a preheating device, which comprises a kiln body and a kiln head cover, a barrel is movably connected to the surface of the kiln head cover, a large gear is fixedly connected to the surface of the barrel, a base is arranged at the bottom end of the barrel, and a small gear is arranged on the upper surface of the base. The oil tank is arranged on the upper surface of the base and can store lubricating oil, the spray gun is fixedly connected to the surface of the oil tank, the large gear and the small gear can be lubricated by spraying the lubricating oil through the spray gun, abrasion of the large gear and the small gear can be reduced through lubrication, and the service life of the large gear and the small gear is prolonged. And meanwhile, a first motor runs to drive a screw rod to rotate, a screw sleeve can move horizontally under the action of the screw rod, then the first connecting rod dr