cwood3
Mechanical
- Jul 9, 2010
- 25
Here's one for you guys.....................
Here is the scenario. The applicable code is ASME B31.3. A53, Gr. B pipe. 26” Std, hence, 0.375” wall thickness. Welding a split “Tee” fitting on for a hot tap operation. The split “Tee” fitting material is A516, Gr. 70 and is 1” thick (for the circumferential weld). The pipe is UT’d at the areas to be welded and the minimum wall thickness is found to be 0.200” thick. Yes, the pipe is old. What is the minimum required, by code, fillet weld size for the circumferential welds on the split “Tee” fitting? Is it 1.4T, where T is the nominal wall thickness, as-purchased (0.375”)? Is it 0.200 x 1.4, where 0.200 is the UT’d thickness? The first scenario would require a 0.525” fillet weld. The second scenario would require a 0.280” fillet weld.
B31.3 defines “T” (with a bar over it) as “Nominal wall thickness of pipe”
B31.3 defines “T” no bar over it as “Pipe wall thickness (measured or minimum in accordance with purchase specification)”
Thank you for your attention
Here is the scenario. The applicable code is ASME B31.3. A53, Gr. B pipe. 26” Std, hence, 0.375” wall thickness. Welding a split “Tee” fitting on for a hot tap operation. The split “Tee” fitting material is A516, Gr. 70 and is 1” thick (for the circumferential weld). The pipe is UT’d at the areas to be welded and the minimum wall thickness is found to be 0.200” thick. Yes, the pipe is old. What is the minimum required, by code, fillet weld size for the circumferential welds on the split “Tee” fitting? Is it 1.4T, where T is the nominal wall thickness, as-purchased (0.375”)? Is it 0.200 x 1.4, where 0.200 is the UT’d thickness? The first scenario would require a 0.525” fillet weld. The second scenario would require a 0.280” fillet weld.
B31.3 defines “T” (with a bar over it) as “Nominal wall thickness of pipe”
B31.3 defines “T” no bar over it as “Pipe wall thickness (measured or minimum in accordance with purchase specification)”
Thank you for your attention