Hot Rolled Structural I Beam Steel

HAISHENG, a reliable China structural steel Manufacturer and one-stop Supplier, stocks Hot Rolled Structural I Beam Steel produced per GB/T 706 with Q235B and Q355B grades. Featuring tapered inner flanges and uneven thickness, it delivers economical cost and easy processing. Widely used for light secondary beams, platforms, supports and temporary lightweight steel structures, it is a conventional hot-rolled section for small & medium-span buildings.

Key Product Features

I. Sectional and Mechanical Characteristics

1. The inner flange surfaces are sloped, with the flange thickness tapering from the inside out; this results in uneven stress distribution across the section and relatively weak lateral stiffness.

2. Hot Rolled Structural I Beam Steel as a single, integral unit without welded joints, resulting in low residual stress and good structural stability.

3. Offers decent bending resistance but average torsional and lateral displacement resistance; unsuitable for long-span, high-wind-load, or heavy-load applications.

II. Economic and Procurement Characteristics

1. A classic product category with a comprehensive range of specifications; widely available in stock, easy to procure, and competitively priced.

2. For the same load-bearing capacity, material consumption is higher than that of hot-rolled H-beams, making it more economical for light-duty structures.

III. Construction and Usage Characteristics

1. Regular shape facilitates secondary processing (cutting, welding, drilling) and accommodates various on-site connection methods.

2. Moderate self-weight makes lifting and installation straightforward; ideal for simple buildings and temporary structures.

3. Features a hot-rolled "black" mill scale finish; can undergo rust removal and anti-corrosion coating as needed to suit indoor and standard outdoor environments.

IV. Comparison with Hot-Rolled H-Beams

1. Lateral stiffness is significantly lower than that of H-beams; unsuitable for use as columns in high-rise buildings or as main beams for long spans.

2. Sectional efficiency is relatively low, requiring more material under heavy loads.

3. Excellent cost-performance ratio; remains widely used in light-duty and simple steel structures.

Uses and Scope of Application

I. Primary Uses

1. Floor/Roof Secondary Beams & Simply Supported Beams: Hot Rolled Structural I Beam Steel are used to support light floor and roof loads, typically in small-to-medium span load-bearing systems.

2. Platform & Walkway Beams: Primary and secondary load-bearing components for industrial plants, equipment platforms, maintenance walkways, and trestles.

3. Brackets & Supports: Fabrication of pipe supports, equipment mounts, wall bracing, and temporary support frames.

4. Purlins & Wall Framing: Roof purlins for light industrial buildings, construction site hoarding, and simple enclosure frameworks.

5. Small-scale Frames, Beams, & Columns: Beams and columns for light steel frames in low-rise, simple structures such as workshops, warehouses, and carports.

6. Construction Machinery Components: Bases for lifting equipment, vehicle chassis, temporary excavation shoring, etc.

II. Scope of Application

1. Industrial Buildings: Light industrial plants, warehouses, workshops, and small storage silos; primarily used for secondary load-bearing components.

2. Temporary/Simple Civil Structures: Construction site temporary facilities, carports, canopies, simple storage sheds, and modular/mobile buildings.

3. Municipal Infrastructure: Municipal hoarding, guardrail supports, pedestrian walkway supports, and small trestles.

4. Electromechanical Support: Pipe rack supports for power plants and chemical plants, equipment bases, and HVAC pipe hangers/supports.

5. Temporary Engineering Facilities: Excavation shoring, scaffolding bases, and temporary load-bearing frames for construction.

6. Other Fields: Agricultural machinery chassis, frameworks for small transport equipment, and simple warehouse shelving.

Key Performance Parameters

Standards: GB/T 706-2016, GB/T 700, GB/T 1591

I. Common Materials and Mechanical Properties

II. Section Designation and Specification Details

1. Designation format: Model + Height (e.g., 10#, 12#, 14#, 16#, 20a#, 20b#). Sub-types (a, b, c) exist for the same height; web and flange thicknesses increase progressively, resulting in higher load-bearing capacity.

2. Section characteristics: The inner flange surface features a 1:6 slope; the flange is thicker at the root and thinner at the edge, resulting in non-uniform stress distribution across the section.

III. Common Specifications (Model + Section Dimensions)

Format: Height × Flange Width × Web Thickness

·10#: 100×68×4.5

·12#: 120×74×5.0

·14#: 140×80×5.5

·16#: 160×88×6.0

·18#: 180×94×6.5

·20a#: 200×100×7.0; 20b#: 200×102×9.0

·25a#: 250×116×8.0; 25b#: 250×118×10.0

·30a#: 300×126×9.0; 30b#: 300×128×11.0

IV. Dimensional and Shape Tolerances

1. Standard fixed lengths: 6m, 9m, 12m; custom cutting available.

2. Straightness (Camber): ≤2mm per meter; total camber ≤0.2% of total length.

3. Twist and end-face perpendicularity comply with national standards, ensuring precision during installation and jointing. 

V. Surface and Processing Characteristics

1. Delivery Condition: Hot-rolled with mill scale (black finish).

2. Workability: Suitable for cutting, drilling, welding, and bending; convenient for secondary processing.

3. Corrosion Protection: Unprotected in its raw state; can undergo rust removal, painting, or hot-dip galvanizing.

VI. Environmental and Structural Parameters

1. Operating Temperature: -20°C to 80°C.

2. Structural Characteristics: Moderate bending resistance; relatively low torsional resistance and lateral stiffness; unsuitable for long spans, high wind-load areas, or primary load-bearing roles in high-rise structures.

3. Load Suitability: Primarily used for simply supported beams and light-load components; avoid long-term eccentric loading.

Specifications Table of Hot Rolled Structural I Beam Steel