Specification and size of submarine valve of oil tank truck: there are different specifications and sizes of submarine valve of oil tank truck on the market. The commonly used specifications and sizes are DN80 and DN 100, which are generally used for medium with lower viscosity, such as oil, water, oil concentrate, etc.; there are also large submarine valves, such as DN 150 (6 inch) submarine valve, which are suitable for medium with higher viscosity, such as crude oil, asphalt, etc.