Flange magnetic properties outside vs inside

[mariolucas75]

Dear forum,

I have I noticed a following - a flange face and flange interior have different magnetic properties rather than its outside surface....
The magnet sticks strongly to a flange from outside and very weakly to a flange face ....
Vessel Nozzle neck has the same behavior - from outside magnet sticks strongly but inside very weakly....

Has anyone got any ideas ? Datasheet says:
Nozzle Neck material - SA 105 N / SA 106 Gr B N
Flange Material SA 105 N

 

[EdStainless]

Do some of these areas have a SS weld overlay?

 

[mariolucas75]

Do some of these areas have a SS weld overlay?

I dont know.....
1) Can such be happening - flange interior to have SS overlay?
2) How to check in place ?

 

[EdStainless]

I don't know, look at the design package.

 

[hacksaw]

pipe size and schedule, and flange size

 

[dvd]

curious if it is related to magnet geometry and flange geometry - how does magnet stick to an unwelded flange from stock?

 

[mariolucas75]

pipe size and schedule, and flange size

Data sheet says:
Nozzle Neck material - SA 105 N / SA 106 Gr B N
8" schedule S/120
FFWN Flange # 150

 

[hacksaw]

What sort of a magnet are you using in your test? It doesn't sound like you are doing particle testing.