Tank semitrailers are heavy - duty vehicles designed for the bulk transportation of liquids and gases. Comprising a tractor unit and a semi - trailer with a large - capacity tank, they are available in various configurations and sizes to meet diverse transportation needs. The tanks can be made from materials such as stainless steel, aluminum, or composite materials, depending on the nature of the cargo, whether it is fuels, chemicals, food products, or other substances. These semitrailers are equipped with pumping systems, valves, and hoses for efficient cargo handling. Safety features, including double - walled tanks, emergency shut - off valves, and leak - detection systems, are integral to prevent spills and ensure the safe transit of goods, making tank semitrailers a vital component of the logistics industry for transporting bulk fluids.