USCG Exam PracticePumps, valves, and piping systems
Under 46 CFR §56.07-10, when a system component such as a valve has a maximum allowable working pressure lower than that computed for the pipe itself, how must the system pressure be determined?
- A. The system pressure is set to the maximum allowable working pressure of the pipe, provided the valve is bypassed during high-pressure operations
- ✓ The system pressure must be limited to the lowest of the component maximum allowable working pressuresCorrect
- C. The system pressure is averaged between the pipe rating and the component rating
- D. The system pressure is set to the component rating only when the component is in the active flow path
Why B is correct
46 CFR §56.07-10(a)(2) requires that where the maximum allowable working pressure of a system component is less than that computed for the pipe or tubing, the system pressure must be limited to the lowest of the component maximum allowable working pressures. There is no provision for averaging or bypassing.
Cited:46 CFR §56.07-10