Flange alignment on sensitive and/or rotating equipment.

[InspectorClouseau]

Morning Gents,

I’m new here so take it easy...

I’ve been putting together an ITP for Flange Bolting using ASME PCC-1 as a guide but I am getting a little confused where it refers to API 686 Part 6, 4.6 through 4.9 for alignment of flanges connected to sensitive or rotating equipment when spring supports are used. I was wondering if there were any spring support experts here that could lend a hand with the set-up.

My main question is; Bearing in mind the requirements of 4.9.4, would it be safe to say that 4.7.4 is a check to see what the flange alignment is without the stops in place, after previously aligning the flanges with the stops in place? Checked before bolting the flanges together in 4.8, but after confirming the flanges are dimensionally aligned as per 4.6, with all temp attachments shims etc removed, piping complete as per 4.7.2...?

Regards to all Inspector.

 

[InspectorClouseau]

OK, maybe a little bit involved.

Can anybody tell me if it is important [or required] to have the flanges stress free with the spring supports adjusted to the cold load position and the stops removed.