Kentucky Boiler Practice Exam

What is the minimum relieving capacity required for a safety valve or safety relief valve?

1. Equal to or exceed the minimum output of the boiler

2. Equal to or exceed the maximum output of the boiler

3. Equal to or exceed the average output of the boiler

4. Equal to or exceed the rated output of the boiler

The correct answer is: Equal to or exceed the maximum output of the boiler

The minimum relieving capacity required for a safety valve or safety relief valve must be able to handle the maximum output of the boiler. This is essential because safety valves are designed to prevent excessive pressure buildup that can occur during abnormal operating conditions or potential failures. If the relieving capacity is insufficient compared to the maximum output, it can lead to the valve being unable to open quickly enough or fail to relieve pressure in time, ultimately resulting in dangerous conditions such as boiler explosions or failures. Therefore, the safety valve must be sized appropriately to allow for the maximum steam flow or pressure that the boiler can generate in any unexpected scenario. This ensures that the system is protected against overpressure while maintaining safe operational limits. It's important for maintenance and operation personnel to remember that the safety valve must always exceed this maximum output to provide the necessary protection for both the boiler and personnel involved.