Boothy104
Nuclear
- Feb 10, 2016
- 3
Hi All,
I'm hoping that one of you guys with more experience in the ASME BPVC Section II NC can help me.
Table NC-4622.7(b)-1
I am having trouble understanding the definitions in this table. The project is providing nuclear valves in accordance with NC. After casting and finished machining we are getting small defects detected by PT/MT. I am hoping that the majority of these defects can be excavated and repaired, with no PWHT, in accordance with this table.
All the repairs will be Groove joints, so lets say we have an LCB body with a wall thickness of 40mm, and the depth of the excavation is 10mm.
The column 'Type of Weld' is what confuses me? The definition in Note 1 states 'Where the thickness of material is identified in the column Type of Weld , it is the thickness of the base material at the welded joint'.
I know which column to use for 'Nominal thickness (4622.3)' - as this is described as the depth of the weld groove, which would be 10mm in this case.
Can somebody describe what 'the thickness of the base material at the welded joint' would be in my example?
Would the base material be the wall thickness (40mm)?
Or the wall thickness (40mm) minus the 10mm excavation, so the base material at the welded groove joint would be 30mm in this example?
It seems a lot simpler for butt weld, as I presume the base material would be the nominal pipe thickness, but in the case of the grove joint is the base material the wall thickness?
Thanks in advance
I'm hoping that one of you guys with more experience in the ASME BPVC Section II NC can help me.
Table NC-4622.7(b)-1
I am having trouble understanding the definitions in this table. The project is providing nuclear valves in accordance with NC. After casting and finished machining we are getting small defects detected by PT/MT. I am hoping that the majority of these defects can be excavated and repaired, with no PWHT, in accordance with this table.
All the repairs will be Groove joints, so lets say we have an LCB body with a wall thickness of 40mm, and the depth of the excavation is 10mm.
The column 'Type of Weld' is what confuses me? The definition in Note 1 states 'Where the thickness of material is identified in the column Type of Weld , it is the thickness of the base material at the welded joint'.
I know which column to use for 'Nominal thickness (4622.3)' - as this is described as the depth of the weld groove, which would be 10mm in this case.
Can somebody describe what 'the thickness of the base material at the welded joint' would be in my example?
Would the base material be the wall thickness (40mm)?
Or the wall thickness (40mm) minus the 10mm excavation, so the base material at the welded groove joint would be 30mm in this example?
It seems a lot simpler for butt weld, as I presume the base material would be the nominal pipe thickness, but in the case of the grove joint is the base material the wall thickness?
Thanks in advance
