not re-drilling holes

[TurbineRepair]

Hi guys,

I've got circular flange with a number (about 60!) of bolt holes in it. Is there any way of masking the holes so that I don't have to re-drill them all after build up with Inconel 718 powder? I'm concerned that if I put anything in there; 1. it might not come out and 2. it might cause a shadow effect around the hole.

Thanks,

Jim

[Steph]

You can use heat resistant rubber plugs and countersink them in the hole a few mills lower then the face to avoid any shadowing, that is the most common way and easiest.

[TurbineRepair]

Thanks Steph, I'll give it a try.

Jim

[Gordon]

Hi Jim

Metal or silicone rubber bungs or putty used as Steph suggested. I've seen special shaped metal bungs being used, but these required the operator to break the coating bridge every few coating passes. Whatever masking system you use, you will probably still need to dress the hole edges, but that will much easier and safer than drilling out a coated hole.