Seamless steel pipes are used for low-pressure fluid transportation and are also known as ordinary straight seam steel pipes. Straight seam steel pipes are mainly applied in water supply projects, petrochemical industry, chemical industry, power industry, agricultural irrigation, and urban construction. For liquid transportation: potable water, drainage. For gas transportation: coal gas, steam, liquefied petroleum gas. For structural purposes:桩管, bridge construction; wharf, road, and building structure pipes, etc.