In the process, are often subject to a variety of external force, and the influence of human factors, it will deform and damage, so that the ship lost normal technical condition, the reason is as follows.
1. external force action
The ship is constantly subjected to bending and torsional stresses due to its constant fluctuation, swing and rotation in waves.
2. corrosion
The corrosion of metals is a natural loss that occurs all the time.
3. anthropogenic effects
Due to the improper use and management of ships, accidents such as average are occurred. The above is a visible damage, and the normal technical condition of the ship can be restored after repair.
4. intangible loss
Due to the progress of science and technology, the technical status of ships becomes obsolete and backward, and needs to be rebuilt, updated or scrapped.
Because of the above reasons, in the process, resulting in loss and damage in different degree, affect the normal technical conditions of the ship, the normal operation of the ship also gradually influence the threat to the safety of the ship. Therefore, it is necessary to repair these defects to maintain and restore their normal technical conditions, and to prevent the continued loss and damage of various components of the ship.