Cast iron pipe

Cast iron proved to be a beneficial material for the manufacture of water pipes and was used as a replacement for the original elm pipelines utilized earlier.

Flanged joints consisted of flat machined surfaces that were tightly bolted together with a gasket between them to prevent leakage.

This type of pipe joint is still in use today, typically for above-ground pipelines in water treatment and manufacturing plants.

Cast iron pipe was frequently used uncoated, although later coatings and linings reduced corrosion and improved hydraulics.

Many public utilities, municipalities, and private industries still have functional cast iron pipe in service to this day.

Mechanical joints were made by bolting a movable follower ring on the spigot close to the corresponding bell, which compressed a gasket in between.

Many water pipes today use mechanical joints, since they are easily made and do not require special skills to install.

A lubricated beveled spigot section can be pushed into this joint with care, as not to roll the rubberized gasket, and once installed became watertight.

This type of jointing system is popular today with ductile iron and polyvinyl chloride (PVC) pipes.

Using this method the slag would all collect at the top of the casting and could be removed by simply cutting off the end of the pipe.

Modern ductile iron pipe production continues to use this general method of casting.

Cast iron pipe formed using this procedure was typically oven-cooled under controlled time and temperature conditions.

In 1939, American Standard A21.4 was published, which defined a Type I cement coating on the inside of waterline pipe to be used.

BS 78 was finally superseded when the UK harmonised with incompatible European standards, however, the specified outer dimensions continue to remain in effect (albeit in metric form) as the standard pipe outer diameter for ductile iron pipe in Australia and New Zealand through the descendant specification, AS/NZS 2280.