Saving type pulling-straightening roller

The invention relates to the technical field of pulling-straightening rollers, and provides a saving type pulling-straightening roller which comprises a first roller body, a second roller body and a built-in cavity, the second roller body is arranged on the outer wall of the first roller body, the built-in cavity is formed in the second roller body, a cooling structure is arranged in the built-in cavity, and wear-resistant structures are arranged at the two ends of the first roller body. By arranging the wear-resistant structures, when the third roller bodies on the two sides of the second roller body are used for a long time and are worn too seriously, the third roller bodies on the two sides of the second roller body can be detached and replaced with new third roller bodies, the third roller bodies and the second roller body are connected more tightly through the square design of the clamping blocks and the clamping grooves, and due to the fact that only the third roller bodies are replaced, the service lif