94 



UNITED STATES COAST GUARD 



If it became necessary to put a hole 

 in the beam in order to support a chain 

 fall for lifting a weight, in what part 

 of the beam would you place the hole? 



What precautions should be taken 

 with respect to shape if a hole is burned 

 out with a cutting torch instead of 

 being drilled? 



Discuss briefly the stresses that may 

 be put on a ship's structure by heating 

 when steaming tanks or heating liquid 

 cargoes to reduce their viscosity. 



What local strength is usually added 

 to a vessel in areas such as illustrated? 



What is the purpose of the frame 

 scallops illustrated, at joints in plating? 



How must the edges of thick plates 

 be prepared for welding? Why? 



When a vessel is to be drydocked 

 where the dock master is unfamiliar 

 with the vessel, what information must 

 be made available to him? 



Describe briefly two or more methods 

 employed to reduce the rolling of ships. 



Describe "panting" stresses and name 

 the structural features of vessels de- 

 signed to resist these type stresses. 



Where the bilge keels of vessels are 

 welded directly to the bilge plating, 

 what precaution must be taken at 

 welded plate butts to eliminate notch 

 eff"ect and danger of cracks? 



Why does the plating thickness of a 

 vessel vary from one part of the vessel 

 to another? 



On the web frame illustrated, what 

 is "A," "B" and "C"? 



Why is the caulk welding of riveted 

 seams as shown below usually avoided? 



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What circumstances or conditions 

 might make a gas-free certificate in- 

 valid and make hot work or other re- 

 pairs dangerous in or near a tank? 



What is a stealer plate? 



What is meant by an A-60 bulk- 

 head? 



Why are most seagoing vessels con- 

 structed with a smoke stack which has 

 an outer casing and an inner smoke 

 pipe? 



Name the types of rivets sketched 

 below. 



3t0U^I 



