At what percentage of the operating pressure does the cut-off valve for a fuel pump typically close?

The cut-off valve for a fuel pump is designed to close at a certain percentage of the operating pressure to prevent overpressure situations that could lead to equipment failure or safety hazards. In most fuel pump systems, this valve is calibrated to close at approximately 80% of the operating pressure. This percentage is strategically chosen to ensure that the system can handle fluctuations in pressure without exceeding safe operational limits.

Closing at 80% helps maintain a buffer zone that allows for minor pressure increases while still protecting the integrity of the fuel system. This design consideration is crucial for effective system operation and safety, as it ensures that the pump does not operate under conditions that could be detrimental to its performance or longevity.