What should I do if the wedge anchor bolt won’t fit after drilling?
1. First check: Is the hole diameter precisely matched?
Standard procedure:
M12 wedge anchor bolts → Must use a 12mm drill bit (no “approximately enough” thinking!)
Specially coated anchor bolts (such as galvanized wedge anchor) → Allow an additional 0.1-0.3mm for the hole diameter.
Measurement method:
Measure the drill bit diameter with a vernier caliper. If the drill bit is excessively worn (e.g., a 12mm drill bit measures only 11.7mm), replace it immediately!
Case lesson: A construction site used a worn 11.5mm drill bit to drill M12 anchor holes, resulting in 30% of the anchor bolts being uninstallable and delaying rework by two days!
2. Key action: Thoroughly clean the hole for dust.
Accumulated concrete debris can clog the hole and reduce anchor strength.
Professional Hole Cleaning Tools:
| Tools | Applicable Scenarios | Effects |
| High-Pressure Air Pump | Drying Concrete Holes | Dust Removal Rate > 95% |
| Nylon Brush | Removes Residual Dust on Hole Walls | Prevents Re-Attachment |
| Vacuum Cleaner | Working at Heights and in Confined Spaces | Safe and Dust-Free |
Don’ts:
× Flushing with Water (Reducing Concrete Strength)
× Digging with Rebar Hooks (Scratching Hole Walls)
3. Fatal Mistake: Forcing Anchor through Bolts in!
Thread Scratches → Nuts Can’t Be Tightened;
Expansion Tube Deformation → Anchor Bolt Failure;
Hole Wall Cracking → Re-Drilling Required (Extending the Repair Area)
Correct Procedure:
1. Allow the anchor to naturally rest in the hole, manually pushing it in to 80% of its depth.
2. Use a rubber hammer to gently tap until flush with the base surface (no more than three taps).
3. If it’s still stuck, → Stop! Remove the anchor and recheck the hole diameter and cleanliness.
4. Emergency Remediation: What to Do if the Hole is Damaged?
If the hole diameter is too large or the hole wall is damaged, refer to the following repair options:
Minor Overshoot (hole diameter > anchor 0.5-1mm):
Inject epoxy anchoring adhesive and then insert the anchor (bearing capacity increases by 30% after curing).
Severe Overshoot/Deviation:
Re-drill a new hole at least twice the hole diameter from the original hole (avoiding rebar).