Steel Fabrication and Erection Process in Los Angeles California
Autor: David AroniSubjects: Bidding process in the Steel Fabrication and Erection Industry ; Phases of Steel Fabrication and Erection
The Structural steel, is designed mainly to support a load, as a frame or for aesthetic reasons. In buildings, industrial or architectonic elements. The structural steel design must comply with AISC and ASTM requirements which indicate the quality of the material; regarding the purpose or function of the structure under real conditions of forces, load, temperature, humidity, chemical attacks, etc., factors and variables that are considered in the design process. By a certified engineer who indicates in the plans all the details of the elements with their standards of quality of the materials, including the certification of the welders who have to perform the welding.
With the approved construction plans, the subcontractors can carry out the estimate at their cost and risk, making the “takeoff” that consists in identifying, measuring and counting all steel elements in its final position. To get: the quantity, quality, characteristics, weight, type of shapes and their unions and welding, and all accessories in their final position in the building and calculate the material, logistic fabrication and erection cost, including the personnel, machinery and schedule that determines the general expenses and profit, for complete the estimation and work plan.
Once the contract has been awarded. The shop drawing is elaborated with the elements in their final position in three dimensions. Usually, the shop drawing is made by the sub-contractor and have to be reviewed and approved by the designer. As the shop drawing is a precise document; It also serves to generate the bill of materials to make the purchase orders.
With the shop drawings approved. The fabrication process begins in the work shop or fabricator´s plant, and the fabrication typically consists of the following steps:
- Cut the proper lengths
- Create templates and or mark steel
- Punch and/or drill holes
- Camber members (If required)
- Prepare accessory steel pieces
- Add shop welded or bolted pieces to members and make special cuts
- Clean members (Can be done before cutting)
- Tag steel members
- Surface treatments (Painting and or galvanizing)
The quality control inspection, normally is carried out at the assembly stage; checking, marking and labeling the examined pieces after measuring, and verifying the weld quality and size for compliance with the design.
The location and diameters of the holes, and the paint and galvanizing quality; also should be checked. After the quality control, the structural steel is delivered to job site, to be erected or installed.
The steel erection is the process of field assembly of structural pieces to create the frame, roof truss or other structures. And usually has the following steps:
- Inspect and clean the area, necessary for maneuvering and lifting loads
- Design and install of temporary bracing system (If needed)
- Steel frame erection
- Correction inspecting and testing.
Article published in December 2022 for KMBJ Structural Steel, INC., as a summary of its production process, and also based on AISC publications.