American Society of Mechanical Engineers (ASME) Practice Exam

The minimum thickness for boiler plate where a stay penetrates is set at 5/16 inch to ensure sufficient structural integrity and safety under the operating conditions of a boiler. This thickness is particularly important because the area around the penetration needs to withstand high pressures and temperatures that are common in boiler operations. A thicker plate helps to prevent issues such as failure at the joints, fatigue, or excessive stress concentration, which can happen if the material is too thin. Choosing 5/16 inch provides a margin of safety that is in line with industry standards, addressing concerns related to potential leaks and strengthening the connection where the stay bolts or stays penetrate the boiler shell. This consideration helps to enhance the overall reliability and longevity of the boiler system, ensuring it operates within safe parameters. In comparison, thinner options do not meet the established guidelines for safety and performance, potentially leading to structural failure or operational hazards. The use of proper thickness is critical in maintaining the design integrity of the boiler and preventing catastrophic failures.