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...
I'm just glad moltenmetal isn't in charge of running the economy (although I suspect it's pretty high on the priority list).
Just a personal story: my home heating bill has in fact decreased every year as the cost of oil has come down. When oil was trading at $120/barrel, I was paying...
We've seen vessels sent in for rebuild that have integral tubesheets attached in this manner (usually the vessel originates from Europe).
As others have pointed out, it is an inferior joint. We always end up replacing the tubesheet and matching it to the shell OD.
-TJ Orlowski
I would expect the result in your asme.pdf to be the most valid result. For cylinders under internal pressure, ASME Section VIII, Div 1 requires the designer to consider both the longitudinal (circ joint), and the circumferential stress (long joint), and use the thicker of the two for required...
Innovation is correct. Either ask the mill / distributor to quote you with sanitary tubing to SA-270 that is also manufactured and certified to SA-249. If that does not work, purchase the tubing in SA-249 regular BA finish, and send the tube to an aftermarket polisher who can clean, polish...
See paragraph U-1(j)
Depends on design pressure and internal volume. Note that a UM stamp is an option (subject to customer / local jurisdiction approval; you can always stamp U.
-TJ Orlowski
GregLocock,
Two other options: Organize a labor union with the other employees, petition an existing labor union to come in and negotiate with the employer on their behalf.
Employers are in no way, shape, or form market-makers; nor do they have the "vast majority of the balance of power."...
In my opinion, anyone that believes, or promotes the notion that employers "exploit" their employees are looking at the situation from the wrong prospective. Employers are not market-makers: they pay for the services of their employees at the rate which the market demands. Nothing more...
Somewhat off topic: I think I know exactly which reviewer at ABSA is looking at ReddeV's heat exchanger. We are currently experiencing a similar bottleneck with one of our designs that already holds CRN approval in multiple other provinces.
It is. . . time consuming.
-TJ Orlowski
Don't you just love it when "new and improved" design formulae condemn equipment that has been working beautifully for decades?!
Suggest you try a cammprofile gasket or reinforced grafoil gasket, something with a low m and y value as fegenbush alluded to. You may also want to try low-stress...
If process engineers are specifying type S heat exchangers across the board, but it could be advantageous to explore using other configurations on a per-application basis, I don't see why you wouldn't weigh other options - if there is the will and the way to do so.
In my view, best practice is...
If your shell-side temperature and pressure are less than 400F and 200 PSIG, and your shell-side fluid is non-corrosive, you may consider a type AEP or BEP configuration. It's been my experience that there are less problems with gaskets vs. type S units.
If you have > 200 PSIG shell-side...
Remember, MTR's and CofC's are supporting documentation. From a dimensionsal standpoint, the part itself controls whether it is acceptable.
If the dimensions on your parts are within the current tolerances, then the parts are acceptable. You should have provisions in your QC manual for...
Brandon181,
Concur with SnTMan: what is the reason that your pressure vessel spec requires that the test gaskets shall not be suppiied with the finished product? Does that reason make sense, and is it even applicable for shell & tube heat exchangers? Mandating that all gaskets be replaced...
Cry22,
From your arrogant (and ignorant frankly) tone, it is understandable that you are "your own boss." If you have any employees, do you view them in the same manner as you assert that those on this fora view their employees? Or are you a divinely inspired exception to the "rule" that...
