When did vessels begin to get MDMT ratings?
If a vessel was built in the early 1960's using SA-285-C, but was not stamped with an MDMT rating, could you now "re-rate" this vessel (give it an MDMT rating) as -20 deg.F using current ASME VIII-1 edition (UG-20f/UCS-66) without having to do...
Is the pipe a "dip-tube" (a pipe projecting inside through a nozzle)? If the pipe you speak of welds to the shell or head as it passes through, then the pipe is part of the pressure retaining boundary and must meet ASME VIII and ASME II material specifications. There should also be...
Was nozzle a RFWN Flg which was cut-off and replaced or rewelded? Or was the nozzle cut-out of the vessel shell and replaced with new fabricated nozzle?
Vessel was originally ASME Code U stamped (code of construction). Repairs and alterations (after inservice) must be made by an R stamp...
You need to find Code stamping of each of the separate pressure boundries (or review the mfr's data report...mayne form P-3 with attachements). There are several different pressure boundaries on a HRSG, and unless you isolate each boundary, just be sure not to overpressurize the lowest boundary...
Large condensor (horizontal tubular ht xchgr) has over 1400 3/4 OD tubes which contain cooling water at 30 psi. The shell surrounding the tube bundle contains a gas/vapor at less than 5 psi. Both the shell side and tube side are rated at 50 psi and Code (U) stamped.
The shell has developed 2...
HRSGs usually have about 3 or 4 separate pressure boundaries that can be isolated for hydrostatic testing during new construction. Each of these separate boundaries has different pressure ratings (MAWPs) and are difficult to isolate once in operation. Be careful not overpressurize lower rated...
I am referring to plugging tubes in watertube boilers, don't think I've seen anyone plug any tubes in firetube boilers.
Metengr....if using SA-s6 then one should perform a thickness calculation? Taperred plug could then be machined to assure at least the calculated thickness is driven into the...
Was the Mig above "short circuiting" process? Short circuiting is 1.1T for max range. But, for spray arc, globular, pulsing methods the max T is still 2T.
You do not count "reinforcement of welds" just base metal thickness. Acceptable weld reinforcement sizes come from the Code of construction.
I keep getting conflicting information regarding acceptable material for boiler tube plugs. I find SA-36 plugs readily available, but some have said that plugs must be made of SA-105 and not SA-36. Anyone else being told this?
Thanks weldtek for the Interpretation reference, this subject keeps coming up more and more lately (using E6010 to weld SA516-70). Previously A-106 would have actually been S number, not P number, but I think they are now all P numbers.
Check with Jurisdiction...if these are new boiler installations, jurisdiction might want Form P-4B completed. If these spools are being installed on existing boilers, jurisdiction (like TN) might want the installation documented on Form R-1 and noted as Mechanical Repair on Line 10 remarks (as...
