Installation of Demister Pad in an Existing Vessel 3

[hhmh2004]

Is it possible to install demister pad in an existing vessel which does not have provision (internal attachment) before? What will be the most cost effective way?

 

[Duwe6]

Easy installation, if there is reasonable access into the vessel. The installing contractor will need to hold an appropriate Vessel Code certificate -- in USA, either an ASME "U" stamp or a NBIC "R" stamp.

 

[Chance17]

Some professionals would call for the safety valve connection be upstream of the demister.
All because the demister can plug
or because it represents an unpredictible restriction in the relief path.

 

[hhmh2004]

will this require welding of internal attachment inside the vessel for demister pad support? This will require an ASME Re-certification. Is there any other way in which I can avoid the welding inside the Vessel OR ASME re-certification...???

Thanks

 

[rmw]

Have you checked with any demister pad suppliers? Some of them have clamping mechanisms designed just for what you are facing. I haven't dealt with it in a while, but I remember one support system that used jack screws to expand the support structure into the vessel walls. They have means to mount their stuff when the vessel wall can't be welded on.

rmw

 

[Duwe6]

Welding does not "require an ASME Re-certification". Just have to have an "R-1" completed for the attachment welds to the pressure shell. The most NDE that the Vessel Inspector would require would be a Visual Exam --VT, and Dye Penetrant -- PT. Then an "R" repair data plate is riveted next to the "U" data plate, and the "R-1" paperwork is put into your file for that vessel.

This would *not* be considered an Alteration, which has mandatory Calc's, and possibly another hydro test.

 

[EuroWeld]

Hello,

I know a scompany that deliveres demisters mounted on a clamp ring. Meaning that their is no welding to install the demister.

The clamps are fixed against the vessel wall by means of springs.
The advantage is that no welding is necessary and it's easy to install and disassembly.

If needed I can search for adress information! please note that this is no advertising.

Kind regards

EuroWeld (the Netherlands)