🔍 Key Concepts

• sacrificial anodes (zincs) and why they are used in saltwater systems • how zincs protect metal parts inside a saltwater cooled heat exchanger • what happens if zincs are coated, insulated, or reshaped

💭 Think About

• Think about the main job of a zinc in a saltwater system: is it supposed to corrode or be protected from corrosion? • If you reduce the zinc’s exposure to seawater (by covering or insulating it), what happens to its ability to do its job? • At what point in its life should a part designed to be slowly used up be replaced—when it’s new, slightly worn, about half gone, or almost completely gone?

✅ Before You Answer

• Remember that zincs are sacrificial—they are meant to corrode first to protect other metals. • Any action that prevents seawater contact with the zinc will also prevent it from protecting the system. • Maintenance practice: know when a sacrificial anode is typically replaced in routine marine service (often tied to a percentage of material remaining).