Different Types of Gas Tanker Ships Gas carriers can be grouped into five different categories according to the cargo carried and the carriage condition. These are as follows:Fully pressurised ships Semi-pressurised ships Ethylene ships Fully refrigerated LPG ships LNG shipsThe first three ship types listed are most suitable for the shipment of smaller-size cargoes of LPG and chemical gases. This is normally accomplished on short-sea and regional routes. Fully refrigerated ships are used extensively for the carriage of large size cargoes of LPG and ammonia on the deep sea … [Read more...]
Gas Tanker Basics – Definitions and Hazards
Transportation of Liquefied Gases by Sea General For economical marine transportation, gas is carried in a liquefied state. As a liquid, the volume to weight ratio at atmospheric pressure is in the range of 650 times less than in the gaseous state. That means we can carry 650 times more cargo in the liquid state as compared to a carriage in the gaseous state.The temperature at which a gas condenses is a function of its pressure. The combination of pressurising and cooling is, therefore, fundamental to gas carrier design. Some ships carry gases liquefied under pressure & others under … [Read more...]
Rule 32 – Definitions
PART D - SOUND AND LIGHT SIGNALS Rule 32 : Definitionsa. The word whistle means any sound signalling appliance capable of producing the prescribed blasts and which complies with the specifications in Annex III to these Regulations.b. The term short blast means a blast of about one second’s duration. c. The term prolonged blast means a blast of four to six seconds’ duration. … [Read more...]
Rule 21- Definitions
Rule 21 Definitionsa. Masthead light means a white light placed over the fore-and-aft centerline of the vessel showing an unbroken light over an arc of the horizon of 225° and so fixed as to show the light from right ahead to 22.5° abaft the beam on either side of the vessel.b. Sidelights means a green light on the starboard side and a red light on the port side each showing an unbroken light over an arc of the horizon of 112.5° and so fixed as to show the light from right ahead to 22.5° abaft the beam on its respective side.In a vessel of less than 20 m in length the … [Read more...]