What must be included in the markings on power plant valves?

The correct answer is based on the requirements for valve markings in power plant operations, which are crucial for ensuring safety, proper function, and compliance with regulations. Markings on valves should provide essential information about the valve's intended use and specifications, which is critical for maintaining safe operating conditions.

Including the service designation helps operators understand the specific application or fluid type for which the valve is intended, ensuring it is used correctly within the system. The manufacturer's name indicates the source of the valve, which is important in case of recalls or when sourcing replacement parts. The material designation informs users about the materials used in the construction of the valve, which affects its compatibility with various fluids, pressure ratings, and temperature limits.

These markings are vital for traceability and safety, making it easier to identify components during maintenance or inspection. Such information prevents the misuse of valves, which could lead to failures or accidents, emphasizing the importance of having comprehensive markings on power plant valves.