A portable or fixed device incorporating one or more corrosion resistant wire woven fabrics of very small mesh which is used for preventing sparks from entering a tank or vent opening or, for a short time, preventing the passage of flames.
In other words flame screen can be explained as :
“flame screen” means a device utilizing wire mesh to prevent the passage of unconfined flames, complying with all relevant requirements of this Schedule;
Fully-pressurised ships carry cargo in pressurised receptacles made of steel which can take a pressure of approximately 17 kg/cm2. The ships are usually small, with a maximum cargo capacity of approximately 1,000 m3. The ship has two tanks which are installed horizontally. The tanks are usually of cylinder shape. Some ships have several spherical tanks, or cylinders placed vertically, or a combination of them.
The ships usually carry LPG or ammonia for a short voyage. The ships’ tanks are usually equipped with a double bottom and some have ballast tanks which are above the cargo tanks. The hold space, which contains the cargo tanks, is ventilated in a way that there is either dry air or inert gas.
The concept semi-refrigerated ships covers a variety of ships. They all have a cargo system of pressurised receptacles, which is suitable for cargo the temperature of which is lower than that of ambient air. The temperature range depends on the steel used. The usual or general temperatures are -33 degree C (for ammonia) and -50 degree C (for LPG).
Fully-refrigerated LPG ships
These ships transport LPG in a temperature of -55 degree C to +0,5 degree C. They may be equipped to transport ammonia and they are usually suitable