Direction4：Technological process of Steel structure processing
⑴Sample rod making
The steel structure template can be made of iron or flat iron with thickness of 0.50 ~ 0.75 mm . When the length is shorter , the wooden ruler rod shall be used . The sample bar and template shall indicate the work number , drawing number , part number , quantity and processing edge , groove location , bend line and bending direction , aperture and rounding radius , etc . The sample bar and template shall be kept properly until the end of the project can be destroyed.
Check the steel structure specification, material, batch number, and clean the surface of steel plate, dirt and spoils. If the surface quality does not meet the quality requirements, the steel structure should be corrected.
Drawing drawing, sample rod, sample plate and steel tape measure are used to make drawing. At present, some advanced steel structure processing plants adopt program control automatic marking machine, which is not only efficient but also accurate. Save material. The essentials of marking have two: ①the work site should not be directly affected by sunlight and outside temperature indoor, had better be open. Bright place. ②the drawing accuracy of drawing needle is higher than that of ink ruler and drawing rope.
The cutting of steel structure includes the methods of gas cutting, plasma cutting and using mechanical forces such as shear, cutting, friction heat, etc. The cutting ability, cutting precision, quality and economy of cutting section should be considered.
⑸Edge machining and end machining
The main methods are: shovel edge, planer edge, milling edge, carbon arc gouging, gas cutting and groove machine processing.
⑹for making holes
In the welding structure, welding shrinkage and deformation will inevitably occur, so in the manufacturing process, to a large extent, grasping when the hole opening will affect the precision of the product.
The methods of steel structure assembly include ground sample method, copying assembly method, vertical assembly method, horizontal assembly method and tire die assembly method.
Welding is a key step in the manufacture of steel structure.
⑼Treatment of friction surfaces
The value of anti-slip coefficient of high strength bolt after friction surface treatment should conform to the design requirements (generally 0.45 ~ 0.55). The treatment of friction surface can be done by sandblasting, shot peening, pickling, grinding wheel grinding and so on. Generally according to the design requirements, when the design is not required, the construction unit can use appropriate methods for construction.
The environmental temperature of coating and numbering shall conform to the requirements of the specification of coating products. If there is no regulation, the ambient temperature shall be between 538 ℃ and the relative humidity shall not be greater than 85%. The surface of the member should be protected from rain within 4 hours after coating. The method and grade of rust removal on the surface of steel member shall conform to the specification. The quality requirements should be in accordance with the national standard, the steel structure surface rust grade and rust removal grade before painting, and the surface rust removal method and the rust removal grade should be suitable to the paint used in the design. The 30mm width of the uncoated and installed welds indicated in the construction drawings The inside and high strength bolt friction joint surface shall not be coated. Paint, coating number, coating thickness shall conform to the design requirements. After painting, the components shall be numbered according to the design drawings. The position of numbering shall conform to the principle of easy stacking, easy installation and easy inspection. For large or important components, the weight and center of gravity should also be marked. The number of the summary data and transport documents, construction organization design documents, quality inspection documents and so on unified, numbering can be repainted after the completion of the inspection. Sizing, laying, cutting, groove processing, opening, assembly (including correction) Welding, friction surface treatment, coating and numbering are the main process of steel structure processing.