Steel structure construction process mainly includes cutting drawing sheet, lofting group vertical forming, etc., the specific process we look at the detailed introduction.

First, lofting, marking work content

Lofting is a process in the production process of steel structure, only the lofting size is accurate, in order to avoid the accumulation of errors in each subsequent processing process, to ensure the quality of the entire component. The content of lofting includes: check the installation size and hole distance of the drawing; Release nodes in a 1:1 scale; Check the dimensions of each part; Make templates and sample rods as the basis for cutting size, bending, hole making and other processing.

When lofting, the large sample is popped out on the lofting table by geometric drawing method at the ratio of 1∶1. After the lofting is checked and correct, the template and sample rod are made of steel plate; Indicate the work number, drawing number, part number, quantity, aperture, etc. on the template and sample rod; Then use the template, sample rod for marking material. When marking materials, check and verify the materials, mark the cutting and drilling positions on the materials, and mark the parts numbers, as shown in Figure 6-16. Samples and rods shall be kept properly until the completion of the project.

Precautions for lofting and marking materials

1) When lofting, it is necessary to consider the processing allowance of milling and planing, and the welding components should be released according to the process requirements.

2) Cut according to the ingredients list and template, save materials as much as possible, and leave a cutting margin according to the cutting method.

Two, cutting

Steel cutting methods include cutting, punching, sawing, gas cutting, etc. Which method should be used in construction according to specific requirements and actual conditions to determine. The steel after cutting shall not be stratified, there shall be no cracks on the section, and the flash, slag and splash at the incision shall be removed. The allowable deviation of gas cutting and mechanical cutting shall comply with the regulations.

Gas cutting

Gas cutting is the use of oxygen and acetylene mixed combustion of high temperature to melt steel, and gas pressure to blow away the slag, forming a slit, to achieve the purpose of cutting metal.

Mechanical cutting

1) Sawing machine.

2) Grinding wheel cutter.

3) Shearing machine, steel punching and shearing machine.

Plasma cutting

Plasma cutting is suitable for the cutting of stainless steel, aluminum, copper and its alloys and other materials, with high cutting temperature, large scouring force, good cutting edge quality, small deformation, can cut any high melting point metal materials and other characteristics.

Third, correction and formation

Set right

In the process of steel structure production, due to the deformation of raw materials, cutting deformation, welding deformation, transportation deformation, will affect the production and installation of components, correction is to cause new deformation to offset the deformation that has occurred. The correction of section steel is divided into mechanical correction, manual correction and flame correction.

Bending forming

Cold bending forming process methods include rolling machine, press bending, top bending, tensile bending and so on.

Fourth, edge processing

In the manufacture of steel structures, the internal structure of the steel plate that has been cut or gas cut will change. In order to ensure the quality of important components such as steel beams or heavy crane beams, the edge needs to be processed, and the cutting amount should not be less than 2mm. In addition, in order to ensure the quality of welding and take into account the accuracy of assembly, the edge of the steel plate should be planed (or shoveled).

5. Making holes

There are usually two methods for making holes: drilling and punching. Drilling is a common method used in the production of steel structures. Punching is the hole produced by punching equipment by punching force, the quality of the hole wall is poor, and it has been less used in the production of steel structure.

There are manual drilling and drilling machine drilling. Manual drilling is mostly used to drill holes with smaller diameters and thinner materials. Drilling is convenient and fast with high precision.