About the crane girder camber arching method introduced

   overhead bridge crane  girder camber arching method, the disappearance of the main beam camber have a certain impact. With the continuous improvement of manufacturing process methods, raising the level of production and operation, this effect is gradually reduced. Can be summarized as the following three arching Method:
       1> main beam webs cutting straight, main beam welding, the use of hammers and the web link in the top cover near the weld beat, so this part of the weld stress release, and have some plastic deformation , a certain upper arch. And on the next cover top pressure or locally using the hammer flame heating, the use of plastic deformation, so that the main girder gantry crane with the requirements of camber. This method, although the release of the stress on the cover welds, but not disappear under the stress plate, under load, the tensile load by the outer cover of the weld, causing tensile plastic deformation, reducing the camber therefore formed by this method is unstable camber. While relying hammer pressed into camber, the material is cured, reducing the ductility.
       2>  hoist gantry crane  girder webs cutting straight, four links and the web using the cover seam welding sequence and the lower part of the lower lid and the web for local flame heating methods, making the main beam produces thermoplastic deformation to achieve design camber. This method relies on the arch formed thermoplastic deformation, under the cover there is a high tensile residual stresses, when the external load, the formation of tensile plastic deformation, reduced camber, camber is unstable.
      3> gantry crane girder webs cutting arched, as the main beams arranged in the upper ribs are more than the upper beam welding emperor lower shrinkage deformation, and therefore must be better than the web camber made ​​after the main camber degree. In this way, the web cutting arched,sino hoist so under load, camber disappear much smaller than the former case, we can see that the degree of camber disappear and manufacturing arch methods.