What element is not typically involved in causing corrosion of pipes?

High pressure is not typically a direct contributor to the corrosion of pipes. Corrosion is primarily an electrochemical process that requires a medium for the reaction to occur. Oxygen and water are two critical components in the corrosion process; oxygen facilitates the oxidation reactions, and water acts as an electrolyte that allows the flow of ions, which is necessary for electrochemical reactions to take place. Chemicals may also contribute to corrosion, depending on the nature of the substances that come into contact with the pipes, as certain chemicals can be corrosive in nature or can create conditions that promote corrosion.

In contrast, while high pressure can affect the physical integrity of materials and lead to stress-related failures, it does not inherently promote the electrochemical reactions that lead to corrosion like the other elements do. Thus, the answer identifies high pressure correctly as not being a typical factor in the corrosion process of pipes.