Rules for lofting, numbering and cutting of steel tower mast structure
1 For lofting and numbering, the welding shrinkage and processing allowance should be reserved according to the process requirements. For the inclined steel pipe ends of the steel pipe tower mast, the inner and outer walls shall be respectively lofted and numbered according to the cutting requirements.
2 The size of the template and the allowable deviation of the hole distance between any two holes on the template is ±0.5MM; the deviation of the hole center is allowed ±0.5MM.
3 When parts are directly numbered, the deviation of length and width should not be greater than 1.0MM; the position of the hole allows deviation.
4 When the tube-shaped web rod is numbered, the relative torsion of the intersecting line at both ends along the circumferential direction should not be greater than 2.0 mm.
5 The scoring of the holes of the bent parts shall be carried out after the parts have been bent and passed the inspection.
6 The allowable deviation of the cutting line and number line of the parts shall meet the following requirements:
7 Before cutting, the rust and oil stains in the cutting area of the steel surface should be removed; after cutting, there should be no cracks and chipped edges larger than 1.0mm on the fracture, and the fusibility and spatter on the edge should be removed.
8 The cutting surface or shearing surface of steel plate and round steel and the tipping degree of the cutting end surface of steel pipe should meet the requirements.
9 The inclination of blanking of various types of steel can be specified according to the allowable inclination of the outer diameter of the steel pipe according to the section size.
10 When round steel is used as the main force-bearing part, three test pieces should be made before cutting the material for physical and mechanical properties and chemical analysis inspection. It can be used in engineering only after all tests are qualified. Punching and cutting of round steel components is strictly prohibited.
