Rail system of an oil supply ship, a method of positioning and arresting a hose, and an oil supply ship

A rail system (40, 40′) of a ship (30) for positioning and arresting a hose (28) for supplying fluid material to an oil rig (10) from the ship (30) or supplying fluid material to the ship (30) from the oil rig (10), said rail system (40, 40′) comprising a rail (44, 44′, 46, 46′, 47) extending lengthwise at an upper edge of a bulwark of the ship (30), a vertical notch (48, 50) being provided in said rail (44, 44′, 46, 46′, 47) having a bottom width corresponding to the diameter of the hose (28), and a locking element (52, 52′) of an elongated configuration being pivotally journaled adjacent to said vertical notch (48, 50) and being shiftable between a vertical position in which the hose (28) may be freely introduced into and positioned in said vertical notch (48, 50) and a horizontal position in which said locking element (52, 52′) is blocking the entry into said notch (48, 50) and rests on the hose (28) for arresting the hose (28) in said notch (48, 50), and said locking element (52, 52′) being journaled on a journaling shaft (54) relative to said rail (44, 44′, 46, 46′, 47) and defining in said vertical position a lower part (56) below said shaft and an upper part (58) above said shaft, said lower part (56) providing an extension extending in said vertical position of said locking element (52, 52′) into said vertical notch (48, 50) for being contacted by said hose (28) for causing, by said hose (28) pressing onto said extension, said locking element (52, 52′) to shift from said vertical position to said horizontal position.