Steel prefabricated steel construction issues, a model of dimensional accuracy and sophistication cutting line cutting use will directly affect the quality of component size prefabricated, steel production in the pre-construction. At the same time cutting and cutting should allow sufficient allowance. From raw materials, after cutting member to preform molding, corrections and shaping the steel construction throughout every step of the process. If the correct procedure embarrassed Organisation steel construction, the next step of the construction will not be guaranteed. Correct style pattern varied, often adopted in accordance with the specific circumstances, but the heating is one of the most common correction means which, due to the heating temperature is too high, the material often leads to the occurrence of the material change, and often use forced cooling water after heating, Even heating zone to produce hot brittle phenomenon. Plates, profiles due to the length restricted. Because of the self-test disassembly, spliced ??between the various processes the order is unreasonable or not strict, and often not even too large deformation correction. Because node does not match, the rift is too large or splicing process is unreasonable. Member is in the stitching. Often resulting in a total length after stitching prefabricated structure distortion. After making the mosaic structure span splice ban. Scantlings stitching or a small spell before the members are not allowed to cumulative deviation is too large. After the completion of steel or precast. Arising as a result of the collision died bend; stacking steel company, to produce death due to bends or slow bend point pad layout is unreasonable or low altitude settlement. Steel mounting feet because of the identity of the weld large steel columns or column base plate is too thin, the foundation elevation deviation is too large or is not leveled foundation details will directly affect the level of the column assembly, vertical, horns and horn blocks composite length. At the same time. Welding process contraction deformation, so that the bottom plate warping, thus affecting the quality of the column assembly. Often resulting position error column axis. Position deviation position foundation anchor bolts or studs are not allowed floor bolt hole is too large. Because the underlying structure of the unit capitals axis offset, when tall steel structure installation. Fulfilling base structure assembly, in order to ensure consistent up and down the column axis, the following layer column centerline axis of the upper column as a baseline installation, making the grassroots capitals axis deviation is too large. Should be finished in time for installation or pre-assembled components of the structure to perform proofreading and permanent steel flow control problem hypothetical hypothetical should pay attention: To reduce steel welding deformation. Welds should be as symmetrical arrangement; not arbitrarily increase the weld thickness; the premise of ensuring safety of welds should not be too concentrated. Construction Control and Prevention. Prefabricated moral restraint, not segmented measurement; after the release of the steel wire size should be the amount of the full-length sub dimensions. Save the cumulative size. For members require a higher dimension, should put the line marked like red eyes. To ensure that the cutting edge of the cutting quality, 12mm below the board should try to mechanical cutting. When cutting with gas welding steel, steel specifications should be considered to extend the margin 2-3mm aside. Should be corrected; deformed steel beyond designated tolerance range. If the allowable value for the scale delineation of cold deformation correction and cold bending radius of curvature of the minimum and maximum bending vectors should be used to correct or use steel pressure jack homemade correct tools to perform cold correction, incident corrections. Style pattern shown in execution; if large deformation of steel or steel installation components, linear expansion -6