How to fix the crane girders sinking failure

  Gantry crane prestressed girder method Hugh complex, there are two basic ways to sink, one hand stretched, the other is mechanical tension. The former with a repair in a small crane lifting weight, which is used for larger sinking from the weight of the crane girder repair.
   (1) lever.  gantry crane  trolley round by the end of the rod and welded rod group, but must ensure that it bit concentricity, after welding, careful examination, testing and inspection should be done conditionally. Round general use 45 steel production, and after heat treatment. To avoid breakage and slider rod end, prestressed rod can be divided into single and double row arrangement. Symmetrical arrangement of the vertical axis of the main beam, rod cloth Ge width should not exceed the width of the main beam, if necessary, enter should not exceed 50mm, rod spacing is determined according to the operation to facilitate the needs of single rod tensile force should not exceed 150kN as appropriate.
       Rod end nut and nut sub-working construction nuts, nut job tensioned by tightening into service and should be applied to pre-fastened side lever to keep the long-term effects prestressing. Work nut requires thick and require end rod of the same material.
    (2) the support frame. Supporting frame structure from the floor, side panels and welded into the ribs. Base plate and end plate requirements smooth outer plane, to ensure the support frame and  hoist gantry crane  girder and working under the cover of dense nut paste. Supporting frame slightly wider than the width of the base plate under the cover of the main beam width of the main beam and floor thickness equal to the thickness under cover. Side plates for the main mechanical parts, generally thicker, the distance between the ribs and rod center distance equal to the distance between side hole to the edge of not less than 80mm.
    (3) hanger. Each door crane girders under the Ge hanger, usually three, L> 22.5m can be set 5. Figure 8-17 is one form. Hangers welded to the main beam only allowed under the cover, not with webs welded.