TJOrlowski
Mechanical
- Jul 16, 2010
- 173
We are getting some pushback from a Canadian safety authority in their review of our application for CRN on one of our straight tube HX designs. The design contains a simple flanged & flued expansion joint per Appendix 5 and TEMA. The flanged and flued heads we are using are small: 10-3/4" OD on the small end, and 18" OD on the big end, and they are manufactured from a single piece of plate with no welds in the heads. We are doing full VE and LP on both sides of all accessible welds from head to head, and where each head attaches to the shell with a butt-weld per para 5-5(c).
The reviewer in Canada is now insisting that all those welds (the circ weld joining the two heads, and the circ welds attaching the expansion joint to the shell) need to be X-rayed 100% per parap 5-5(b). We (and our AI) do not agree, as para 5-5(b) states that welds within the flexible element need to be examined this way. Para 5-4 defines the flexible element as the flanged and flued head. Not both heads welded together (the expansion joint).
Is our interpretation correct? If so, any guidance on how we might diplomatically present this to the design reviewer at the safety authority in Canada to get them to agree and get this project closed?
-TJ Orlowski
The reviewer in Canada is now insisting that all those welds (the circ weld joining the two heads, and the circ welds attaching the expansion joint to the shell) need to be X-rayed 100% per parap 5-5(b). We (and our AI) do not agree, as para 5-5(b) states that welds within the flexible element need to be examined this way. Para 5-4 defines the flexible element as the flanged and flued head. Not both heads welded together (the expansion joint).
Is our interpretation correct? If so, any guidance on how we might diplomatically present this to the design reviewer at the safety authority in Canada to get them to agree and get this project closed?
-TJ Orlowski