As a carrier on the water surface, ship repair can maintain its balance on the water surface without capsizing? It depends on the stability of the ship. When the hull is repaired when the ship is tilted under the action of external force, its stability will exert the effect to generate a turning moment, and the ship can return to a normal equilibrium state under the action of the moment. The so-called stability, that is, the GM value, refers to the interval between the center of gravity and the center of buoyancy. When the center of gravity is above the floating center, the GM value is negative; when the center of gravity is below the floating center, the GM value is positive; when the center of gravity overlaps the floating center, the GM value is zero, that is, the stability disappears.

The stability of a sailing ship is a dynamic value, which will change under the influence of wind and waves, so that the ship will tilt. The greater the tilt angle, the greater the stability loss, and the greater the restoring moment. When the ship is tilted due to external action, if the turning moment cannot correct the ship back before the stability of the ship disappears, the ship may capsize.

Then, what are the main external forces that cause the ship to tilt?

First of all, the weather.

The external scene image sea waves, winds, etc. will generate external forces on the ship and cause the ship to tilt. Wind and waves are the main factors. The wind will exert pressure on the surface of the ship and cause the ship to tilt. The larger the wind area of the ship, the greater the impact. , Such as passenger ships, container ships, ro-ro ships, etc. The other is swelling. When the ship is sailing, the hull collides with the swell, and the external force generated by the swell may also cause the ship to tilt. Therefore, external factors such as the sky are an important factor that causes the ship to tilt, especially the extreme and bad weather.

Second, in addition to the weather, will the ship's operation be tilted?

Of course, in the process of turning, the ship will tilt to the inner direction of the rotation in order to maintain the stability and speed. The faster the speed, the more significant the tilt, and the faster the turning speed, the more significant the tilt, so this will cause the ship to turn The loss of stability in the process leads to severe tilt and even overturning. The smaller the ship's draft, the more significant the tilt when turning, such as passenger ships and empty cargo ships. In the case of a small draft, if the steering speed is fast, it is easier to cause tilt. One way to avoid excessively fast steering speed is to avoid steering with a large rudder angle when using the rudder. The steering angle of the rudder angle is small, and the speed will be relatively slow, because the ship tilt caused by the steering will not be very significant.

Then, from the above content, due to the weather and operation, the ship may tilt and cause the stability of the ship to be lost. The severe stability becomes zero or even the stability becomes negative, and then capsizing may occur. It can be inferred that the greater the stability, the smaller the stability loss of the ship when it tilts, and the less chances that the stability will become negative, such as sailing ships. Therefore, we can often see that the sailing ship is tilted at a large angle. Will not overturn.

So under what circumstances will the ship be more stable? What factors can increase the stability of a ship? What factors will affect the stability of ships? This is the issue of ship stowage.

For ships, whether it is a cargo ship or a passenger ship, the cargo cabin is the most important part of the ship, and it is also the most important factor that easily affects the stability of the ship. When a cargo ship accepts load-bearing tasks, the captain is responsible for ensuring that the ship is within a reasonable range of stability. Passenger ships are difficult to control because of the mobility of passengers. However, passenger ships can be arranged in a layered and reasonable manner according to shipbuilding regulations to ensure sufficient stability. Because passenger ships have a smaller draft and are less stable than cargo ships, the passenger ships are equipped with ballast tanks during the manufacturing process for the captain to adjust stability.

Generally speaking, on the bottom of the ship, there will be corresponding ballast water tanks, fresh water tanks, oil tanks, etc., which will have an impact on the stability. If the captain thinks that the configuration of the passenger and cargo tanks is detrimental to the stability of the ship, he can adjust the pressure The water tank is used to increase the stability of the ship. For ships on long voyages, especially ships with poor stability such as wooden ships, it is also necessary to consider the influence of fuel consumption and fresh water consumption on the stability of the ship during the voyage. The captain is responsible for the actual situation of the ship. , Navigation area, weather conditions, etc. to make professional and fair arrangements to ensure the safety of ships.