MILD STEEL PIPES
Several pipe types fit into this category, a consequence of method of steel manufacture and pipe fabrication.
Early “steel” pipes are also known as “locking bar” and rivetted wrought iron pipes. These pipes are lead jointed using couplings, with tar type lining and coating. They are prone to leak.
Modern steel pipe manufacture began in the 1920’s coinciding with spun factory cement mortar linings. They exhibit a range of coatings, and jointing techniques. The pipes are fabricated by welding plate steel into pipe lengths.
Steel is tough and ductile, and modern steel pipes initially “fail” by leaking.
Low carbon steel
Micrograph courtesy of University of Cambridge