A fillet weld patch is installed on a vessel with a 144" inside diameter and a wall thickness of 0.750". What is the minimum allowed spacing between this patch and another nearby patch?

A fillet weld patch is installed on a vessel with a 144" inside diameter and a wall thickness of 0.750". What is the minimum allowed spacing between this patch and another nearby patch?

• A. 25.5"
• B. 29.4"
• C. 36"
• D. 40"

Answer: (B)

The minimum allowed spacing between patches on a pressure vessel is crucial for maintaining the vessel's structural integrity and ensuring appropriate stress distribution. According to relevant codes and standards, particularly those associated with pressure vessel inspection, the spacing between patches should be determined based on the diameter of the vessel and the characteristics of the patches themselves. For a vessel with a diameter of 144 inches and a wall thickness of 0.750 inches, the spacing is influenced by the need to prevent overlapping heat-affected zones from adjacent welds, which could weaken the material. The calculation typically involves a formula or guideline established in industria standards that may reference factors such as the diameter of the vessel and the size and type of the patch being applied. In this case, the choice of 29.4 inches aligns with the standards and engineering practices for ensuring that there is an adequate distance between the patches. This distance helps to ensure that the integrity of each patch can be achieved without interference from an adjacent patch, reducing the risk of failure due to the interaction of stresses around each patch. While other distances may seem plausible, they do not meet the calculated or recommended requirements for the specific configuration of the vessel in question, which results in them not being the appropriate answer. Therefore, a spacing of

The minimum allowed spacing between patches on a pressure vessel is crucial for maintaining the vessel's structural integrity and ensuring appropriate stress distribution. According to relevant codes and standards, particularly those associated with pressure vessel inspection, the spacing between patches should be determined based on the diameter of the vessel and the characteristics of the patches themselves.

For a vessel with a diameter of 144 inches and a wall thickness of 0.750 inches, the spacing is influenced by the need to prevent overlapping heat-affected zones from adjacent welds, which could weaken the material. The calculation typically involves a formula or guideline established in industria standards that may reference factors such as the diameter of the vessel and the size and type of the patch being applied.

In this case, the choice of 29.4 inches aligns with the standards and engineering practices for ensuring that there is an adequate distance between the patches. This distance helps to ensure that the integrity of each patch can be achieved without interference from an adjacent patch, reducing the risk of failure due to the interaction of stresses around each patch.

While other distances may seem plausible, they do not meet the calculated or recommended requirements for the specific configuration of the vessel in question, which results in them not being the appropriate answer. Therefore, a spacing of