For large pressure vessels, a lift plan is a critical part of the overall design and should not be overlooked. The lift plan specifies the locations of lifting and tailing points and verifies that no vessel components are overstressed during handling. Because vessels that operate in the vertical position are typically shipped horizontally, the designer must evaluate the lifting stresses throughout the full range of motion during the up-ending process. As the lift progresses, the direction and magnitude of forces at each lift point change, requiring careful analysis. In addition to verifying the structural adequacy of lift lugs or trunnions, the designer must also confirm that the supporting shell or head is not overstressed or permanently deformed during lifting. A properly designed lift plan ensures the safety of the vessel, lifting equipment, and personnel throughout the entire vessel installation.