Step Bolts Ultimate Guide: Types, Materials, Standards & Applications 2
4. Structural Composition of Step Bolts
4.1 Head
One-piece forged widened head, the core load-bearing stepping surface. Its thickness and width directly determine maximum load capacity; heavy-load projects specify extra-thick heads.
4.2 Step Surface
The flat stepping plane, available in smooth or anti-slip textured styles. Textured surfaces prevent slipping on rainy or frosty days for safer high-altitude work.
4.3 Shank
Smooth unthreaded middle section, customized in length to match plate thickness. Short variants are fully threaded, while long models retain a smooth transition shank.
4.4 Thread
Standard UNC coarse thread delivers stronger bite resistance against loosening under outdoor vibration; UNF fine thread is only available for custom orders.
5. Common Types of Step Bolts
5.1 Classified by Head Shape
- Hex Head: Square neck anti-rotation design, mainstream choice for heavy towers, largest stock availability
- Round Head: Vintage style for wooden poles without square neck, lower cost, less common in new projects
- Special Custom Heads: Extra-wide or raised irregular heads per client drawings, requiring separate moulds with high minimum order quantities
5.2 Classified by Step Surface Design
- Single Step: One-sided wide stepping surface, standard universal model for most projects
- Double Step: Stepping platforms on both sides with doubled load capacity, used for high-voltage towers and wind power facilities
- Anti-slip Serrated Step: Embossed anti-slip teeth on stepping plane, mandatory for rainy, snowy and frost zones
5.3 Classified by Installation Method
- Through-hole Mounting: Pre-drilled plate holes with bolt penetration, simplest construction adopted by 90% of projects
- Weld-on Mounting: Bolt base pre-welded to poles, ideal for old towers under renovation without drilling allowance
- Custom Mounting: Special structures such as extended bases or clamping slots per client drawings
Practical Distinction:
Choose weld-on variants for tower renovation; through-hole installation speeds up construction and simplifies part replacement for new builds. Anti-slip models carry slightly higher unit cost but greatly reduce high-altitude slip hazards, often enforced as mandatory by engineering contractors.
6. Common Materials for Step Bolts
6.1 Carbon Steel
6.2 Alloy Steel
6.3 Stainless Steel
7. Surface Treatment Options for Step Bolts
7.1 Hot Dip Galvanized (HDG)
7.2 Zinc Plated (Electro-galvanized)
7.3 Dacromet
7.4 Black Oxide
7.5 Mechanical Galvanized
7.6 Other Anti-Corrosion Coatings
