Introduction to Side Scuttle
A marine side scuttle is a circular window, which is divided into three types: heavy, middle and light. Heavy duty side scuttle with windproof inboard hinged side scuttle. The side of the side scuttle cover is fitted with a rubber seal, which is bolted to ensure water tightness. Light side scuttle generally do not have weather covers. Marine side scuttle on premises below freeboard deck or enclosed superstructure premises are heavy side scuttle. side scuttle are fixed and movable, the former can not be opened, the latter can be opened, according to the watertight pressure capacity of heavy 20Pa, ordinary 50~100Pa, light (below 20Pa). Heavy duty side scuttle in a watertight area with a riot cover, such a window will not be able to maintain light during storm weather. The marine side scuttle is round, and the diameter of the transparent glass used in the specification is usually ø200mm, ø250mm, ø300mm, ø350mm, ø400mm, depending on the size of the ship (rib distance). The double escape hatch must be above ø350mm.
Overview
Marine side scuttle installation requirements
In accordance with the requirements of the current International Loadline Convention, side scuttle shall not be positioned so that their sills fall below a line drawn parallel to the boundary line of the bulkhead deck, the lowest point of which is 2.5% of the ship's width above the deepest subdivision loadline or 500mm, whichever is greater. Where the pane is below the limit line, it shall be constructed so as to effectively prevent any person from opening it without the master's permission. For side scuttle between decks, a line shall be drawn parallel to the bulkhead deckside line, the lowest point of which shall be 1.4m above the water when the ship leaves any port and 2.5% of the ship's width. When the side scuttle sills are below this line, all side scuttle between decks shall be closed watertight and locked until the ship leaves port and such side scuttle shall not be opened until the ship reaches the next port. The time at which such side scuttle are opened in port and the time at which they are closed and rewound before the ship leaves port shall be entered in the prescribed log book.
No side scuttle shall be provided in any premises exclusively for the loading of cargo or coal.
Automatic ventilation side scuttle should not be installed on the outer panels below the boundary line without special permission.
When the round side scuttle is opened on the side roof, the porthole is usually reinforced with flat steel or web.
Why are marine side scuttle round?
The reason why the marine side scuttle is designed to be round is not for aesthetic reasons, but there is a certain scientific reason. According to the principles of mechanics, the circle can withstand stress such as pressure and shear better than other shapes. (When the material is deformed, the internal reaction force of equal but opposite direction is generated to resist the external force, the concentration of the distribution of internal force at one point is called stress) If the marine side scuttle is made into a rectangle or diamond shape, when they are subjected to external pressure, shear and other forces, the stress will be concentrated on the corner of the rectangle or diamond; when the stress is large to a certain extent, the angle of the marine side scuttle is often deformed or broken. This will greatly reduce the strength of the hull structure and affect the safe navigation of the ship. The round marine side scuttle is different. When it is a part of the external force, it will distribute this external force evenly to all parts. To a large extent, this can avoid the phenomenon of damage caused by excessive concentration of stress in a certain place. According to the mathematical principle, under the condition of a certain circumference, the area of a circle is larger than that of any other shape; this means that when the amount of construction and the phenomenon of leakage and leakage are roughly the same, the circular marine side scuttle has the largest amount of light. In addition, the round shape is very beautiful. Based on the above reasons, the designers chose the circle as the shape of the marine side scuttle.
