USCG Exam PracticeHydraulics and pneumatics
What is the minimum number of pressure relieving devices required on a hydraulic system under 46 CFR?
- ✓ One, set to relieve at the system's maximum operating pressureCorrect
- B. Two, one at the pump outlet and one at each actuator
- C. One, set to relieve at twice the system's maximum operating pressure
- D. One per actuator, each set to the actuator's rated pressure
Why A is correct
46 CFR §28.405(c) and §28.880(c) require at least one pressure relieving device set to relieve at the system's maximum operating pressure. The regulation specifies a single device minimum and ties the relief setting to the maximum operating pressure, not a multiple of it.