SPECIMEN EXAMINATION FOR MASTER 



99 



Why might the stress for which the 

 deck beam brackets provide part of the 

 resistance be strongest at the vessel's 

 midlength than at bow and stem? 



When scupper and sanitary discharge 

 pipes lead through the ship's side below 

 the freeboard deck, how must they be 

 fitted to prevent water from passing 

 aboard? 



In the construction or the repair of 

 gratings for use on the decks near a 

 switchboard or resistor panel, would 

 you use nails or wooden dowels? Why? 



What basic considerations are fol- 

 lowed in the design and maintenance of 

 ships to ensure that they are rat proof? 



In machinery spaces where sources of 

 vapor ignition are normally present, 

 why should at least one vent duct go 

 as low as possible? 



Describe briefly how heavy steel cast- 

 ings, forgings, etc., are examined by 

 magnetic particle testing (magniflux- 

 ing) for cracks or flaws invisible to the 

 eye. 



In the construction of a vessel, how 

 must fire hydrants be spaced and ar- 

 ranged? 



What are : 



(a) Soft patches? 



(b) Hard patches? 



How are they fastened on and made 

 watertight? 



How is a B-15 bulkhead constructed 

 to prevent the spread of fire? 



Why is insulating material necessary 

 on steel or aluminiim bulkheads which 

 are constructed to prevent an excessive 

 rise of temperature on the unexposed 

 side as well as prevent smoke and flame 

 passing? 



In freeing up a reach rod, would pro- 

 cedure "A" or "B" be preferable? Why? 



Is a mushroom vent as at "B" or a 

 porthole as at "A" satisfactory for 

 ventilation of a battery room? Why? 



How must vessels of over 1600 gross 

 tons be fitted in order that failure of 

 the side, masthead, range, or stem 

 lights is indicated at once to the officer 

 on watch? 



Why do chain falls hold a load in 

 position usually without the necessity of 

 securing the hauling part? Why do 

 tumbuckles hold a weight without se- 

 curing against turning or walking 

 back? 



What effects does vibration have upon 

 such devices as chain falls or turn- 

 buckles? 



DECK 



•TWESN SECK 



HOLD 



