What happens when the pressure setting of a pressure relief valve is reached?

When the pressure setting of a pressure relief valve is reached, the correct response is that some flow is diverted back to the tank. Pressure relief valves are designed to maintain a safe pressure level within a system by allowing excess pressure to escape. When the pressure in the system reaches the set limit of the valve, it opens, allowing fluid to flow through the valve and return to the tank or reservoir. This action helps to prevent potential damage to the system components that could occur if the pressure exceeds safe operating levels.

The proper function of a pressure relief valve is crucial for maintaining system safety and integrity. By diverting some flow back to the tank, the valve prevents pressure buildup, thereby ensuring that the system remains within operational parameters. This operation helps protect pumps, piping, and other equipment from the risks associated with overpressure conditions.

Other options like the valve closing completely, the pump stopping, or flow through the system ceasing do not accurately describe the function of a pressure relief valve, as it is precisely designed to relieve excess pressure rather than completely shut off or eliminate flow.