1. Pre-construction Preparation

• Design and Drawing Review: Before construction, conduct a thorough review of the design drawings. This involves checking for errors, omissions, and ensuring constructability. A joint review by designers, contractors, and supervisors is crucial to resolve issues early

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• Raw Material Quality Control: Strictly control the quality of steel and other materials like welding rods and high-strength bolts. Ensure they have complete quality certificates and undergo necessary re-inspections to confirm they meet design standards

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• Construction Organization Design: Develop a detailed construction plan and quality control scheme. This should address potential problems, define sequences (especially for lifting and installation), and set quality standards

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📐 2. Foundation and Embedded Parts

• Foundation Accuracy: The foundation's axis, elevation, and especially the positioning of embedded anchor bolts​ must be precisely controlled. Even minor deviations can affect the entire superstructure's alignment. Re-measure and confirm these values before concrete pouring and after it sets

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• Anchor Bolt Protection: Protect the threaded parts of anchor bolts from damage and corrosion during concrete pouring, often by wrapping them

  . Before column erection, clean the bolts and apply grease .

   

🔩 3. Steel Component Installation and Connection

This is the most critical phase for structural integrity.

• Lifting and Hoisting: Develop a specialized lifting plan. It must define the lifting sequence (typically from a stable bay near the gable outward, and from main to secondary beams), lifting points, and temporary support measures to prevent deformation or collapse

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• Component Correction: After a component (like a column) is hoisted, temporarily brace it immediately. Use tools like经纬仪 (theodolites) to carefully correct its verticality​ and elevation. Correction should consider environmental factors like temperature

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• High-Strength Bolt Connections: The friction surfaces of connected components must be clean and dry. Bolts should be freely inserted—forced insertion or reaming holes is prohibited. Tightening must follow a strict sequence (typically from the center of a joint outward), performed in initial tightening and final tightening stages using a calibrated torque wrench

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• Welding Quality Control: Welding is a special process requiring strict control. Welders must be certified. Use qualified welding procedures: pre-clean the welding area, preheat if necessary, and control parameters. After welding, conduct visual inspections and Non-Destructive Testing (NDT) like ultrasonic testing for critical welds to detect defects like cracks or porosity

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• Error Control: Monitor cumulative errors during installation. Regularly survey the installed structure's axis and elevation to prevent small deviations from adding up to unacceptable levels

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🛡️ 4. Anti-Corrosion and Fireproofing

• Surface Treatment: Before painting, steel surfaces must be thoroughly cleaned of rust, oil, and dust. Shot blasting​ is commonly used to achieve the required cleanliness and roughness grade, which is essential for paint adhesion

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• Coating Application: Painting should be done in a dust-free environment with suitable temperature and humidity. Control the paint mix ratio, number of coats, and dry film thickness​ to meet design specifications. Inspect the coating for uniformity, absence of leaks, and good adhesion

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• Fireproofing: Apply fire-resistant coatings as required. The application thickness and evenness must meet the design's fire resistance rating

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⚙️ 5. Safety and Management

• Safety Measures: Implement strict safety protocols for high-altitude operations, lifting, and temporary electricity use. Erect safety nets and require personal protective equipment (PPE). During installation, use缆风绳 (guy ropes) to stabilize structures

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• Documentation and Acceptance: Maintain complete records for each step: material certificates, inspection reports, welding logs, and completion acceptance records for each sub-project

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In summary, successful steel structure factory construction hinges on meticulous control from design and materials to precise installation and connection techniques, all underpinned by rigorous quality checks and safety management.