Vessel Jacket Best Practices
Vessel Jacket Best Practices
(OP)
Hello,
I'm putting together a Best Practice for Vessel Jackets. It will include the fabrication process and applications for conventional, half-pipe, and dimple jackets. I was wondering if anyone had any ideas of some common problems and what to look for when fabricating the vessel jacket that's not necessarily written in the ASME code but is based on experience and lessons learned. Additionally, I would like to get an idea of some applications of each jacket and which one is best suited for certain applications.
Thanks
I'm putting together a Best Practice for Vessel Jackets. It will include the fabrication process and applications for conventional, half-pipe, and dimple jackets. I was wondering if anyone had any ideas of some common problems and what to look for when fabricating the vessel jacket that's not necessarily written in the ASME code but is based on experience and lessons learned. Additionally, I would like to get an idea of some applications of each jacket and which one is best suited for certain applications.
Thanks





RE: Vessel Jacket Best Practices
One big problem for jacketted vessels is the differential pressure during hydrotesting of the jacket. If you are not careful of the application of the test pressure then you can exceed the allowable pressure for the inner vessel. Normal "trick" is to pressurise the inner vessel to ensure the differential external pressure does not exceed the allowable.
RE: Vessel Jacket Best Practices
If the vessel was constructed as * 0.500" nominal * amd there is a spot that actually reads 0.494", that first Internal Inspx at X years will give a Corrosion Rate of 6 mils per X years. The proper action when you see that high a Corrosion Rate is to go back into the vessel in x/2 years and see if the calculated Corrosion Rate is 'real', or came from a pre-existing 'thin' spot. Taking and mapping some thicknesses during construction, or at delivery [prior to comissioning] will save 1 to 3 unneeded Confined Space entries, at many thousands of $$$.
RE: Vessel Jacket Best Practices
Some years ago, I was involved in a half-pipe reactor design for a major Pittsburgh chemical company. The two otions offered by the fabricator were fillet welded and full penetration welded. I was told that the full penetration welded design would sustain cycling thermal service much, much better than the cheaper fillet welded design.
The full penetration option would take much longer and was subject to additional QC.
Since the chemical reactor vessel would be subject to many deep thermal cycles in service, the client selected the full penetration design.
RE: Vessel Jacket Best Practices