Q- Which of the following conditions can develop if a valve with a badly scored valve stem is repacked?
a)the valve disc will crack
b)leaking and premature failure of the packing
c)the valve disc will become eroded
d)the valve seat will sustain damage due to fretting
Q- You have a two stage centrifugal pump, with both stages in parallel configuration. after dismantling the pump you realize that you forgot to the marking and both impellers are identical.both the impellers are single entry type and the eye of both the impellers will come in opposite direction what are you going to do?
a. since marking was forgotten, so we need not worry, any impeller can come in any place as they are identical
b. any impeller can come in any place, but the phase sequence of the electrical motor driving the pump may have to be reversed, if impellers have exchanged places
c. you have to find out the right placement of the right impeller with respect to the direction of rotation or by looking at the volute casing
Q- If two centrifugal pumps, driven by two independent electric motors, operating at unequal speeds are discharging an inflammable liquid through a common discharge line, the higher speed pump may cause the slower pump to
d)overspeed the driving end
Q- When there is excessive ingress of water in the engine room onboard causing dangerous levels of bilge water,
A.Start oily water separator and pump overboard
B.Start General service pump and pump bilges overboard
C.Use bilge injection valve and pump bilges overboard
D.None of the above
Q- Which of the following is the material used for manufacturing tube plates of a shell and tube type heat exchanger?
B. Aluminum Brass
C. Admiralty Brass
Q- which of the following valve is liable to open or close under pressure of fluid,if not locked in position?
Q- During prolonged astern manoeuvring of the relative expansion between any of the turbine its casing is likely to increase for an alarming level you should (multi choice) in photo no3 in download
A) Inform the bridge that no further manoeuvring is possible as the turbine are likely to be damaged
B) Reduce the vacuum further to control the relative expansion
C) Keep manoeuvring irrespective of damage to the turbines
D) Request the bridge to try to reduce number of astern movements