The underbody check and troubleshooting

A, underbody check 
(a) check: the content of the propeller, rudder, submarine gate, dome and underbody, etc. 
(2) check before stocking 
First get in touch with the captain of the ship being inspected, to stop the car, the rudder, bottom rope for hanging dive flag and arrangement, and according to the ship's request and check the content being inspected ready for special tools. 
(3) the diver along the bottom line descend 
1, to examine the rudder, check to see if the integrity of its representation and deformation, rudder and rudder blade damage, etc. 
2, to examine the propeller, look at the integrity of propeller blade, exposed propeller shaft ever involution, shield and dome fixed screw, etc are in good condition; 
3, the bottom valve inspection, check to see if its appearance in good condition and have blocked; 
4, other underwater vehicle inspection, such as dome, cathode protection devices, bow thrusters and the external hull is in good condition. To check the situation and the problems found, should be timely report, and the caller will inspection results recorded in "the diving record sheet," divers after water, to keep a record of the diving record sheet content to confirm and sign it. Divers should give results in written form to the ship. 
Second, troubleshooting 
(a) free propeller involution 
When the propeller is the involution such as rope, wire rope, or fishing nets, light person affect ship speed and cause mechanical wear, the person that weigh is caused by suspension of the ship. In this case, you need a diver to relief involution. Before liberation, divers to see involution and sequence, to determine free foul methods and tools. Such as foul rope not twisted at one end, can release this end first, with the end in the opposite direction to be foul by the foul on around a circle, in the end is a guide line, the water surface mechanical force round for free. Can also be commanded by divers, cabin free artificial turning in the opposite direction. Such as involution is too tight to relief, chisels, hand saw, special scissors and underwater arc cutting to release oxygen, but should not to damage other components for the principle. 
(2) clean up the bottom door 
Submarine gate generally caused by aquatic organisms, weeds, debris jam. Cleaning method is simple, with scraper, stylus shaving. Such as shield block, divers can clear off guard, once the shield rust, discharge is not come down, plugging method, can be used by the engine room clean, and divers will leak equipment unloading.