5. What are the common types of heads used in pressure vessels, and how do they compare?
The Expectation: Critical understanding of NDT limitations. Model Answer: "In double-wall single-image (DWSI) radiography of pipe or vessel welds, the 'blind spot' is the top and bottom of the weld cap. The X-ray shoots through the top of the weld and the bottom of the weld simultaneously. This superimposition makes it impossible to detect planar defects (lack of fusion, cracks) that are perfectly aligned with the radiation beam. To cover the blind spot, we take two shots 90 degrees apart, or we use tangential techniques." static equipment interview questions
Ready to create a quiz? Use Canvas to test your knowledge with a custom quiz Get started To cover the blind spot, we take two
The simultaneous action of tensile stress and a corrosive environment (e.g., chloride SCC in stainless steel or caustic SCC in carbon steel). To cover the blind spot
: Which paragraph of the ASME code is used for the design of shell thickness?
PWHT is a controlled heating and cooling process applied to welded equipment. The intense heat of welding leaves behind high residual stresses and alters the mechanical properties of the heat-affected zone (HAZ). PWHT is performed to: Relieve residual tensile stresses caused by welding. Reduce hardness and improve ductility.
Fully radiographed (100% X-ray inspected) weld joints. E = 0.85: Spot radiographed weld joints.