Most marine biological sewage treatment plants consist of all the following statements except ().
A、aeration tanks
B、settling tanks
C、disinfection agent
D、anaerobic bacteria
Most marine biological sewage treatment plants consist of all the following statements except ().
A、aeration tanks
B、settling tanks
C、disinfection agent
D、anaerobic bacteria
Which of the following problems will occur if the internal drain at either end of a hydraulic, two-way, spool-type directional control valve cylinder were to become plugged?()
A、The reservoir would become vapor bound
B、The valve would be placed in hydraulic lock
C、The spring loaded relief ports would open
D、The buffering chambers would be unable to function
To safeguard the operator and other personnel working on or near a hoisting operation which of the following precautions should be observed?()
A、Keep a load on the hoist until all personnel are finished working
B、Set the load on a movable dolly when transportation may be needed
C、Have one man keep a hand on the load to steady it
D、Insure that the lifting gear capacity is not exceeded
Basically the bedplate consists of two (), which run the length of the engine.
A、longitudinal girders
B、transverse girders
C、fore girders
D、aft girders
The thermal expansion valve responds to the()
A、amount of superheat in the vapor leaving the coil
B、amount of superheat in the liquid
C、temperature in the evaporator coils
D、pressure in the evaporator coils
Most anchor handling equipment incorporates () for mooring purposes.
A、cable lifters
B、spur wheels
C、bollard
D、warpends