What type of valve is used to redirect pressure back to a reserve tank in a hydraulic system?

The relief valve is designed to manage pressure within a hydraulic system by redirecting excess pressure back to the reserve tank. When the pressure reaches a predetermined level, the relief valve opens, allowing fluid to flow back to the tank rather than remaining in the system, which prevents damage due to overpressure conditions. This function is essential for maintaining safe operating conditions and protecting other components within the hydraulic system.

Flow control valves, on the other hand, are primarily used to regulate the flow rate in a system rather than managing pressure. Holding valves maintain pressure in specific parts of the system but do not redirect pressure back to a reserve tank. Pressure gauges are instruments used to measure the pressure of the fluid within the system but do not control or redirect it directly. Thus, the unique capability of the relief valve makes it the correct answer to this question.