In order to resolve the puzzle that the scaling on the inner wall of the drill pipe seriously restricts the safe， high-quality， and efficient implementation of wire-line core drilling， the comprehensive study was conducted on the scaling mechanism and influencing factors of diamond wire-line core drilling on the inner wall of the drill pipe. The results indicate that： When the structure of the drilling tool and the performance of the drilling fluid are constant， the solid content and particle size in the drilling fluid are the main factors affecting the scaling of the inner wall of the drill pipe. The particle size of rock cuttings produced by diamond core drilling ranges from 5 to 100μm， it is generally small and difficult to remove by the natural settlement. For the reason， the TGLW series small centrifuge is developed. Field tests have shown that the centrifuge can increase the peak value of solid particles in drilling fluid from 5~80μm to 3~10μm， the median particle size of the solid phase ranges from 11.189μm to 3.513μm， the solid phase clearance rate reaches over 90%， and the solid phase content of the drilling fluid is controlled below 0.5%， which not only maintains the performance of the drilling fluid but also prevents scaling on the inner wall of the wire-line drill rod.