The various types of hatch covers that are mainly used on board are as follows –
- Lifting type
- Folding type
- Rolling type / Sliding-type
- Stacking hatch type
Lifting type
Lifting-type hatch covers can be classified into two types –
- Single hatch covering the hold space
- Multiple hatches covering the hold space
Single panel cover consists of a single cover for each opening, these can be seen mainly on bulk carriers. And the multi-panel covers, a single hold is covered via multiple numbers of covers, these are most commonly observed in container ships
Folding Type
Folding type hatch covers are also commonly known as MacGregor type of hatch cover. The efficient use of cargo space is of utmost importance for general cargo vessels. Folding hatch covers are designed to carry various deck cargoes and to form functional cargo areas to facilitate flexible cargo operations. In an open position they provide access to the hold for loading and discharging cargo and in the closed position they seal the hatchway in a weathertight manner.
Rolling Type
In Rolling type hatch covers consists of two covers at the end of the hatchway. Wheels are fitted which help in the sliding of the panel either athwartship.
side-rolling hatch covers can have a variety of different drive systems. The two main options are rack-and-pinion or chain-drive.
Advantages
- Hydraulic or electric-drive lifting operations
- Rack-and-pinion or chain-drive types
- Manual or auto-cleating systems
- Bearing pads for ease of installation and to minimise friction and wear
- Reliable sealing solutions to match hull deformations
- Adjustable fittings (to compensate for wear)
Stacking hatch type
This type of hatch covers are used in small ships like barges, One of the main reason which makes stacking of hatches possible is lesser weight of hatch covers. If you see the Lifting type hatches they can also be lifted and stacked one above the other infact it is a common practice in container vessels but the difference is the weight of the hatch in case of large vessels in we stack hatch covers it might happen that we damage the hatch covers.
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