🔍 Key Concepts

• Stuffing box purpose in a centrifugal pump and what "packing" actually does • How air leakage affects pump suction and priming (air vs. liquid at the packing area) • The function of a lantern ring (seal cage) and when it is used

💭 Think About

• Which component specifically deals with introducing or maintaining a liquid barrier around the shaft to keep air from being drawn in? • Think about which choice is designed to have liquid under slight pressure at the packing area, rather than just squeezing packing tighter. • Which option is commonly associated with sealing the suction side of pumps so they do not lose prime by sucking air along the shaft?

✅ Before You Answer

• Verify which option provides a liquid barrier to prevent air being sucked into the pump, not just mechanical compression. • Check your understanding of a lantern ring: is it for lubrication/cooling, or for forming a liquid seal against air entry? • Make sure the answer addresses air leakage on the suction side of a centrifugal pump, not just general leakage control.