What material should pipe fittings in gas piping systems be made of?

In gas piping systems, the choice of material for pipe fittings is critical for ensuring safety and durability. Malleable iron and cast iron are the preferred materials because they possess high strength and excellent resistance to pressure, making them suitable for handling natural gas and propane in pipelines.

Malleable iron fittings can withstand the stresses of gas distribution systems, including temperature fluctuations and pressure changes, which minimizes the risk of leaks or failures. Additionally, they are capable of being securely connected to iron or steel pipes, maintaining the necessary integrity within the piping system. Cast iron is also commonly used in certain applications due to its ability to handle various environmental conditions.

While other materials such as stainless steel and copper can be suitable in specific situations, and aluminum and bronze offer some advantages in certain contexts, malleable iron and cast iron are specifically recommended for their robust performance and compatibility with gas systems as outlined in many industry standards and building codes.