Carbon steel is an alloy with carbon and iron, with carbon content up to 2.1% by weight. The increase in the carbon percentage will raise steel’s hardness and strength, but it will be less ductile. Carbon steel has good properties in hardness and strength, and it is less expensive than other steels.
Seamless steel pipe, as the name suggests, is a pipe without a seam or a weld-joint. Seamless steel pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases (fluids), slurries, powders and masses of small solids.