Pipes made by mild steel contain carbon contents of less than 0.18%, and is therefore not hardened because of low carbon content. Mild steel is available in a variety of structural shapes that are easily welded into pipe, tube, tubing etc. Mild steel pipes and tube are easy to fabricate, readily available, and cost less than most other metals. In well protected environments, the life expectancy of mild steel pipe is 50 to 100 years.Generally, these pipes are coated with other metals such as copper, to protect from corrosion.