Tank shaped use the advanced welding technology, end socket arc butt welding, and the once-forming of composite steel-plastic technology. Equipped with active and passive safety devices to meet an emergency and can load and unload the material in long distance and completely close condition. Be applied to transport varied oil, feul and chemical material, such as natural gas, liquefied petroleum gas, liquefied ammonia, carbon disulfide, epoxy ethane, gas, butane, dimethylmethane, propylene, etc. Cross section of tank could be oval, round and round-square. heat insulation and heating device is optional.