Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Shell Openings Reinforcement Pads

Status
Not open for further replies.

Kaymo

Mechanical
Mar 2, 2019
3
0
0
MA
According to API650, for the shells thickness grater than t > 12.5 mm, the Minimum Dimension Between Weld Toes shall be 8W or 150 mm (6 in).
On our tank, two nozzles DN250 had 560mm from their center lines, the outer edges (toes) of their normal reinforcing-plate fillet welds are less than eight times the size of the larger of the fillet welds, less than 150 mm (6 in).
In this case and in order to meet the API650 requirements,these openings shall be included in a single reinforcing plate that shall be proportioned for the largest opening in the group.
Due to the fabrication error,these nozzles was fabricated with separate reinforcing plates (nozzle A:Regular type reinforced opening with circular shape reinforcing plate,nozzle B:Low type reinforced opening using tombstone type reinforcing plate). please refer to the attached sketch.
such the openings was done on shell (28Thk)and nozzle B Low type reinforced opening using tombstone type reinforcing plate was done, is there any solution to fix this issue and comply with the API code?
 
 https://files.engineering.com/getfile.aspx?folder=1e2f26d5-40ea-44b9-b863-735d84bf5ce9&file=Capture.PNG
Replies continue below

Recommended for you

Note: the W in 8W is the shell thickness, not the fillet weld size.
What API Group is the shell material, was PWHT performed or required?
In my opinion: to remain compliant with the standard, the repads should be removed and a single one installed. I'd perform NDE on the shell under the removed welds. The new repad could be split on the horizontal centerline of at least the lower nozzle to make it easier to install.
 
Status
Not open for further replies.
Back
Top