Cast Iron Mean?
Cast iron (CI) is one of the materials used for the purpose of making sewer pipes. Cast iron was widely used before polyvinyl chloride (PVC) pipes and concrete pipes came into existence. With thick walls and long lifespans, CI pipes installed in the 19th and early 20th century are still in good working condition except for portions of damaged pipes that need replacement.
Trenchless rehabilitation methods such as sliplining and pipe bursting have made replacing damaged pipe sections quicker and easier than traditional dig and replace methods.
Trenchlesspedia Explains Cast Iron
The manufacturing process of cast iron involves the melting of pig iron, scrap iron and steel in a furnace at approximately 2732° F (1500° C). At this stage, contaminants present in the melt are removed after which the iron is cast. To manufacture ductile cast iron, a magnesium alloy is injected.
A centrifugal casting system is used for the purpose of casting pipes. The pipes are annealed at 1760°F (960° C) in a continuous furnace to break down the cementite into ferrite and graphite. Pipes manufactured for the purpose of sewer pipes are lined with an alumina based cement lining. Usually, wastewater pipes are painted brown.