What is supplied to the stuffing box to lubricate and flush the packing or mechanical seal?

The stuffing box requires a fluid to lubricate and flush the packing or mechanical seal to ensure proper functioning and longevity of the components. Seal water is specifically used for this purpose. It serves as both a lubricant and a flushing agent to remove particles and debris that may accumulate around the seal. This action helps maintain a proper seal while preventing overheating and excessive wear of the packing material or mechanical seal itself.

Using seal water effectively can also help to create a barrier against contaminants entering the system, thereby preserving the integrity of the equipment. This is crucial in maintaining operational efficiency and preventing potential failures in pumps and other machinery. Other options like lube oil, cooling fluid, and hydraulic fluid may have their specific applications in machinery but do not provide the same flushing and maintaining capabilities necessary for the stuffing box as seal water does.