What is the most common cause of electrochemical corrosion in piping systems?

The most common cause of electrochemical corrosion in piping systems is due to electrolytic reactions. This type of corrosion occurs when metal surfaces are exposed to an electrolyte, such as water containing salts and other ions, which facilitates electrical conductivity. In these environments, the electrochemical processes lead to the oxidation of metal atoms, essentially causing them to lose electrons and corrode.

These electrolytic reactions can result from various factors, including stray electrical currents, galvanic cells formed between different metals in contact, and the presence of biological organisms, which can also affect the rate of the corrosion process. This phenomenon is a significant concern in water treatment and distribution systems, as it can compromise the integrity of metal pipes and components, leading to leaks and failures.

The other options represent different processes that can affect piping systems but do not primarily cause electrochemical corrosion. Mechanical wear typically refers to physical erosion due to abrasion or friction, while chemical reactions with air pertain more to oxidation processes. Scaling from minerals is related to the deposition of minerals on surfaces rather than the electrochemical degradation of the metal.