Introduction to Steel Truss Square Head The steel truss square head is a key rigid connection component at the end of the steel Rigging Hardware truss system. It is mainly used to realize the precise docking, load transmission and overall stability enhancement of steel truss units. With its high - strength structural design and perfect compatibility with steel trusses, it finds extensive application in heavy - load scenarios such as large - scale stadium stands, Truss Accessories industrial plant load - bearing structures, and outdoor large - span exhibition trusses. I. Core Functions: Focusing on "Rigid Connection" and "Load Transmission"
1. Precise Docking of Truss Units
The steel truss square head is usually integrally formed or welded at the end of the steel truss main pipe. Truss Hardware Accessories Its square shape (common cross-sectional dimensions: 150mm×150mm-300mm×300mm) has a positioning function—when splicing two truss units, the square heads on both sides can be quickly aligned (the alignment deviation is ≤1mm), avoiding the problem of difficult docking caused by the rotation of circular interfaces. At the same time, the square structure can limit the lateral displacement of the truss after splicing, and the anti-sway performance is 20%-30% better than that of circular connectors. 2. Efficient Transmission of Multi-Directional Loads
The square head is designed with a "thickened stress-bearing structure"—Stage Hardware Accessories its thickness is 1.5-2 times that of the truss main pipe (e.g., if the truss main pipe wall thickness is 6mm, the square head thickness is 9-12mm), and 4-8 groups of high-strength bolt holes (aperture 12-18mm) are evenly distributed on the surface. After the trusses are docked, high-strength bolts (Grade 8.8 or 10.9) are used for fastening, so that the vertical load (such as the weight of equipment and floors) and horizontal load (such as wind load and crowd lateral force) borne by the truss can be evenly transmitted through the square head to the adjacent truss units, avoiding local stress concentration at the splicing interface and reducing the risk of truss deformation or fracture. 3. Enhancement of Overall Structural Stability
In large-span steel truss systems (span ≥15m, such as stadium roof trusses and Steel Truss Square Head workshop crane trusses), the square head not only plays a connecting role but also acts as a "stress transfer node". By matching with auxiliary components such as diagonal braces and cross braces (the square head is reserved with interface holes for auxiliary components), the force between the truss units forms a stable triangular or rectangular force system, which significantly improves the overall anti-overturning and anti-bending capabilities of the truss structure.
II. Core Structure and Material Characteristics
1. Basic Structural Design
Stress-Bearing Main Body: It is a square hollow or solid structure (hollow for lightweight under medium load, solid for heavy load). The inner wall of the hollow square head is provided with reinforcing ribs (spacing 30-50mm) to prevent local deformation under pressure; the solid square head is suitable for ultra-heavy load scenarios (such as industrial trusses bearing ≥5t equipment Structural Steel Truss Square Head).
Bolt Hole Layout: The bolt holes are symmetrically distributed along the center of the square head to ensure that the force is balanced when the bolts are tightened. The hole edge is designed with a chamfer (angle 15°) to avoid stress concentration caused by sharp edges and facilitate the insertion of bolts.
Connection Interface with Truss: The end of the square head connected to the truss main pipe is designed with a "step-type socket", which is nested with the truss main pipe and then fully welded (weld height ≥8mm, no false welding or missing welding), ensuring that the square head and the truss form a rigid whole and preventing the square head from falling off due to load impact.
2. Material and Surface Treatment
Core Material: It is made of the same material as the steel truss to ensure material compatibility and force consistency. For medium-load trusses (such as exhibition trusses), Q235 low-carbon steel is used (tensile strength ≥375MPa); for heavy-load trusses (such as industrial and stadium trusses), Q345 high-strength steel is used (tensile strength ≥470MPa), and the Heavy Duty Steel Truss Square Head sulfur and phosphorus content in the material is ≤0.045% to avoid material defects affecting load-bearing performance.
Anti-Corrosion Treatment: It adopts the same anti-corrosion process as the steel truss to ensure that the splicing interface does not rust first:
Indoor dry scenarios (such as workshop trusses): Sandblasting and derusting + two coats of anti-rust paint (dry film thickness ≥80μm), with an anti-corrosion life of ≥5 years;
Outdoor or humid scenarios (such as stadium outdoor stands and open-air exhibition trusses): Hot-dip galvanizing treatment (zinc layer thickness ≥85μm) or galvanizing + electrostatic spraying (total coating thickness ≥120μm), which can resist rain erosion and ultraviolet radiation, and the anti-corrosion life is ≥8 years.
III. Selection and Installation Precautions
1. Selection Principles: Matching Truss Specifications and Load Requirements
Cross-Section Matching: The cross-sectional size of the square head must be consistent with the end size of the steel truss (e.g., a 200mm×200mm steel truss should be equipped with a 200mm×200mm square head). transparent;">If the truss main pipe is thickened, the square head should also be customized with a thickened structure to avoid mismatching Galvanized Steel Truss Square Head.
Load Adaptation: For medium-load trusses (bearing ≤2t), select hollow square heads (wall thickness 8-10mm); for heavy-load trusses (bearing ≥2t), select solid square heads or hollow square heads with reinforced ribs, and the rated load of the square head should be ≥1.2 times the actual load of the truss to reserve a safety margin.
2. Installation Specifications: Ensuring Safety and Reliability
Pre-Installation Inspection: Check whether the square head has cracks, deformation or rust (if rust is found, derust and repaint); confirm that the bolt holes are unobstructed and the hole position deviation meets the requirements (≤1mm).
Bolt Fastening Requirements: Use high-strength bolts of the specified grade (do not replace with ordinary bolts); when tightening, use a torque wrench to apply torque according to the bolt specification (e.g., M16 Grade 8.8 bolts require a torque of 190-220N·m), and adopt the "diagonal cross tightening method" to ensure uniform stress on the square head.
Post-Installation Inspection: After installation, tap the square head with a hammer (light force) to check for loose sounds; use a level to verify the straightness of the spliced truss (the straightness deviation per meter is ≤2mm); for outdoor trusses, check whether the anti-corrosion coating of the square head is intact, and repair it in time if there is damage.
IV. Typical Application Scenarios
Stadium Fixed Stands: The steel truss square head is used to splice the stand load-bearing trusses (span 15-25m), which bears the weight of the stand floor and the crowd (per square meter load ≥500kg), and the square head ensures that the truss does not deform under long-term use.
Industrial Plant Crane Trusses: The solid square head is used to connect the crane track trusses (bearing ≥10t), which can transmit the horizontal traction force of the crane and the vertical weight of the lifted goods, ensuring the safety of the crane's operation.
Outdoor Large-Span Exhibition Trusses: The hot-dip galvanized square head is used to splice the exhibition main trusses (span 12-18m), which resists outdoor rain and wind load (can withstand ≤6-level wind), and the square head's positioning function ensures the efficiency of on-site rapid assembly.
Wuxi Zhongshengwei Metal Products Co., Ltd.
Contact Now