单项选择题The main advantage of improved Simplex tailshaft seal are()

A.the good sealing performance and the simple structure
B.the good sealing performance and the short life expectancy
C.the good sealing performance but the short life expectancy
D.the good sealing performance and the lower cost


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1.单项选择题Simplex tailshaft seal equipment’s working condition is terribleThe main cause is ()

A.the shafting’s vertical vibration
B.violent friction and sea water corrosive
C.friction and high temperature
D.violent friction and high temperature

2.单项选择题The center line condition of the transmission shaft can be checked by()

A.the border flange’s excursion and flection
B.the both end shafts line’s accordance
C.the border flange’s flection and the both end shafts line’s accordance
D.the border flange’s accordance and both end shafts flection degree

3.单项选择题In the navigation() cause the shafting over load easily.

A.the stopping engine suddenly
B.the sailing astern and changing direction suddenly
C.the sailing from the shallow water area to the deep water area
D.the ship’s trim too much

4.单项选择题When the vessel on the full speed ahead, if full astern immediately () the main engine start astern and fuel injection.

A.after the thrust power is zero
B.after the torsion is zero
C.surpass the critical point on the water turbo phase
D.after the speed is zero

5.单项选择题According to the Robinson Graph, suddenly astern maneuvering of main engine during navigating will cause()

A.rapid reduction of ship’s friction force
B.shaft system over mechanical load
C.sharp growth of the torque of diesel engine
D.propeller torque change along J=0 curve

6.单项选择题While a ship with twin screw is making a turn, in order to prevent overload, the duty engineer should ()

A.reduce the fuel feeding of main engine of inner propeller
B.reduce the fuel feeding of main engine of outer propeller
C.firstly reduce the fuel of main engine of inner propeller, then reduce the fuel feeding of engine of outer propeller
D.reduce fuel feeding of two engines at the same time

7.单项选择题If anything abnormal be found on the load change of main engine when the ship is entering in shallow waterway, before taking measuring the engineer on duty should ()

A.stop main engine immediately
B.ask the captain and the chief engineer’s permission for stopping the engine
C.initiatively inquire the bridge for the situation
D.stop engine and inform bridge

9.单项选择题When ship navigating in rough sea, the first measure taken by the chief engineer to prevent the overload should be()

A.cleaning fuel oil, lubricating oil and seawater filter
B.reducing fuel feeding of the main engine appropriately or reducing the pitch angle of propeller
C.using low sea chest
D.closing the skylight and the ventilation opening, which doesn’t affect the normal work of equipments

10.单项选择题When ship navigating in rough sea, the correct operation is ()

A.navigating with a low diesel engine speed
B.navigating with a stable diesel engine speed
C.increasing the efficiency of propeller
D.increasing fuel injection