What is the maximum allowable height for tanks under API 650?

• A. 40 feet (12 meters)
• B. 50 feet (15 meters)
• C. 66 feet (20 meters)
• D. 80 feet (24 meters)

Answer: (C)

The maximum allowable height for tanks constructed under API 650 is 66 feet (20 meters). This height limit is established by the standards set forth in the API 650 code, which governs the design and construction of welded storage tanks specifically for oil and other liquids. The specification outlines various criteria relating to tank design, including structural integrity, stability, and material considerations.

The 66-foot limit helps ensure that tanks can maintain adequate performance and safety under the various loads they may experience, such as liquid contents, wind, and seismic events. Additionally, exceeding this height may introduce complexities in construction and maintenance practices that could compromise the overall safety and functionality of the tank.

While other height options may seem permissible, they do not adhere to the established standards set by API 650, which emphasizes safety and design consistency across welded tanks used for liquid storage.