Difference between forged steel and carbon steel?

Forged steel has been subject to high temperature and pressure forcing the crystal structure

closer together and increasing tensile strength (used in high pressure gas compressors). Carbon steel is conventional steel produced by the Bessemer process. In the oil industry carbon steel is the default option for casing and tubing used in oil wells but it is not very resistant to

corrosion.

In wells with corrosive compounds such as H2S or CO2 it is often replaced by more expensive 13Cr steel (stainless).