Which material is most commonly used for sewage piping?

The most commonly used material for sewage piping is cast iron. This choice is based on its durability, strength, and ability to withstand the corrosive environment typically found in sewage systems. Cast iron pipes are not only resistant to high pressures but also have excellent sound-dampening properties, which help minimize the noise from the flowing sewage, making them suitable for urban areas.

Additionally, cast iron pipes have a long service life, often exceeding 50 years, and their installation is relatively straightforward. They can also be easily joined together, which is essential for the extensive networks of sewage pipelines found in municipal waste systems. Their resistance to various chemicals found in waste makes them a practical choice for sewage applications.

In contrast, while stainless steel and cast steel offer high strength and corrosion resistance, they are not commonly used for sewage due to higher costs and the likelihood of aggressive corrosion in certain environments. Similarly, aluminum is lightweight and resistant to corrosion, but it lacks the necessary strength and durability for heavy-duty sewage applications, which is why it is not a preferred material for this purpose.