The application of screws is introduced in detail.:1, first clear the fault surface of screw breakage of sludge with center will be death pistol in the center of the cross section and drill bit 6-8 mm in diameter in the center section of the pistol hole drilling, hole must be drilled through. After the hole drilling, the little bit is removed, and the drill bit is changed to 16 mm in diameter, and continues to expand the hole of the broken screw bolt and drill through.2, the diameter of 3.2 mm below the electrode with small current in a broken bolt hole from the inside to the outside welding surfacing to parts of the take off half the entire length of bolts can be. At the start of the surfacing approach arc not too long so as to avoid the broken bolt is arranged on the outer wall of the burning through. Surfacing to broken bolt end to continue surfacing out a diameter 14-16 mm high, 8-10 mm cylinder.3. After surfacing with hammer hammer hit the surface of the bolt breakage along the axial direction vibration. Due to the previously arc generated heat and subsequent cooling and at this time of the vibrations will cause the broken thread of the bolt and the body of the loose generated between.4, careful observation when found percussion has traces of rust from the leakage of the fracture can take M18 nut sleeve on the stigma of the surfacing and bonding between the two.5, welded, and a cool while hot with a plum blossom wrench nut on the left and right back and forth can twist boundary wiggles side with a small hammer tapping nut end so you can remove the broken bolt.6, remove the bolts off with the appropriate tap in the frame will be processed again to remove the threaded hole rust and other debris.