What is the function of lantern rings in a stuffing box?

What is the function of lantern rings in a stuffing box?

• A. Distribute water, protects the shaft and the shaft casing
• B. Provide lubrication
• C. Increase suction
• D. Seal water tight

Answer: (A)

Lantern rings are placed around the shaft inside a stuffing box to deliver lubricant to the packing. Their perforations let oil (or another lubricant) pass from the supply into the space between the ring and the packing, creating a continuous lubricating film around the shaft. This reduces friction and wear, dissipates heat, and helps flush away contaminants, helping the packing last longer and maintain a good seal. While some systems use water as a carrying fluid for cooling or flushing, the primary function of lantern rings is to provide lubrication to the packing rather than to seal or increase suction.

Lantern rings are placed around the shaft inside a stuffing box to deliver lubricant to the packing. Their perforations let oil (or another lubricant) pass from the supply into the space between the ring and the packing, creating a continuous lubricating film around the shaft. This reduces friction and wear, dissipates heat, and helps flush away contaminants, helping the packing last longer and maintain a good seal. While some systems use water as a carrying fluid for cooling or flushing, the primary function of lantern rings is to provide lubrication to the packing rather than to seal or increase suction.