How is packing in the pump feed stuffing box typically lubricated?

In pump systems, the packing within the stuffing box is typically lubricated by allowing controlled leakage through the stuffing box. This leakage serves a dual purpose: it prevents the packing from overheating and ensures that the packing maintains a proper seal around the shaft. The moisture from the leaked fluid helps to lubricate the packing, reducing friction and wear as the pump operates.

Allowing leakage is a common practice because it can also assist in removing debris and contaminants from the packing area, further enhancing the effectiveness of the lubrication. Additionally, it is essential to maintain an optimal balance of leakage; too much can lead to excessive fluid loss, while too little can result in overheating and premature failure of the packing.

The other methods mentioned, like using a separate lubricant reservoir or external grease fitting, are not standard practices for lubricating the packing in stuffing boxes, and immersing packing in lubricant is typically not practical either. The leakage method strikes a balance between maintaining lubrication and ensuring efficient operation of the pump.