Holes restored by welding.

Errant bolt holes have been concealed by filling the hole with weld material.

 

1.      This type of fix should not be used for concealing errant bolt holes. Fill with HS bolt and washers when possible.  Do not attempt weld repair without approved weld procedure.

 

2.      If this type of welding has been noticed, if the position permits, drill out entire weld and install high strength bolt with two hardened washers.  Drill bit must be slightly larger than and centered on original hole to remove most of the heat affected zone and potential micro cracks present.  Before installing bolt, MT and PT inspection by contractual ASNT Level II.  Must be done at fabricator’s expense.

 

3.      If position (or stress) precludes the above bolted repair, drill out and inspect the welded area as above, then fill the hole either cosmetically or structurally.

 

4.      If the drilled hole is partially or completely covered but stresses and proximity of other connections do not require solid metal (for example a bolted diaphragm angle), fill the hole with a steel pin secured by brazing, epoxy, etc. and grind flush.

 

In the case where a plate will cover the errant hole another method to fill the hole using molten zinc has been a viable fix with certain DOT’s.  The procedure includes chamfering the top and bottom, clean and coat the inside of the hole with a zinc-rich primer, preheat to 200 F and fill the hole with molten zinc.  Grind flush, then clean and coat the area.