Plate is a rectangular shape steel with a certain thickness. The most common place you can see the plate in ship construction is the main deck and side of the ship.
Shell Plating
Shell plating is the outer-most structure on the hull of a ship. The main purpose of shell plating is to provide watertight skin of the ship.
Based on the position of shell plating most common types of shell plating are,
> Bottom shell plating
> Side Shell Plating
> Deck plating
Side shell plating is the shell plating on the sides of the ship that forms the watertight skin along the ship side
Bottom Shell Plating
Bottom shell plating is the shell plating on the bottom part of the ship. Or we can say that bottom shell plating form the watertight skin of the bottom of the ship
Deck Shell Plating
Shell plating which forms the main deck of the ship is called deck shell plating.
Shell plating is not made of a single plate it is made of smaller sections of plates welded together. These plates are joined together and numbered in a certain pattern.
See below picture
Each section of the plate placed in fore and aft direction is called a strake. According to above pic we can say A strake, B strake, C strake etc
Shear Strake
It is the top most strake of the side shell plating.
Suppose the picture above is a side shell plating then the top most strake ie, in this case E strake is shear strake..
Keel Strake
Keel plate is also made up of smaller sections of the steel plates. These strake of plates that form the keel of the ship are called Keel Strake.
Garboard Strake
Garboard strake is the first strake on each side of the keel strake. Suppose the above picture is from keel then A strake is the garboard strake.