Methods for Hole Making in Steel Structure Engineering
2025-03-27 
262
With the increasing application of steel structures in our surroundings, operators need to thoroughly understand relevant techniques. The following are hole-making methods for steel structure engineering:
1.Drilling
Preferred method for creating holes in steel structures.
Suitable for any thickness; minimal damage to hole walls.
2.Punching
Limited to non-circular holes and thin plates (<5 mm for general structures, <12 mm for secondary structures).
Initial punched diameter must be 3 mm smaller than the nominal size if reaming is required.
3.Precision Hole Processing
Pre-drill + reaming (3 mm undersized for <5 layers; 6 mm undersized for ≥5 layers).
For multi-layer plates:
4.Drilling Techniques
Use twist drills for through holes, pointed drills for blind holes.
Group drills recommended for thick/high-strength materials.
5.Elongated Holes
Drill both ends + oxygen-cut the middle (length > 2×diameter).
6.High-Strength Bolt Holes
Must be drilled (no punching allowed).
