Novel large-diameter diamond combined drill bit

The utility model discloses a novel large-caliber diamond combined drill bit which comprises a reaming drill bit body and a plurality of reaming blades, the reaming blades are all fixed on the side wall of the reaming drill bit body, a slurry channel is arranged in the reaming drill bit body, slurry nozzles are arranged on the side wall of the reaming drill bit body, and the slurry nozzles are all communicated with the slurry channel. According to the scheme, a combined large-diameter diamond drill bit is adopted, the drill bit is divided into a reaming drill bit body and a detachable cutter, and all the parts are manufactured respectively and connected into a whole through conical threads and screws. Therefore, not only is the difficulty of a large-diameter drill bit manufacturing technology and manufacturing equipment solved, but also when the drill bit is locally damaged, the drill bit can be repaired through a local dismounting and replacing method, and the use cost is greatly reduced. All the components