What is the material placed in rings around a shaft of a pump and used to control leakage from the stuffing box. A steady (1 per second) drip is normal.

What is the material placed in rings around a shaft of a pump and used to control leakage from the stuffing box. A steady (1 per second) drip is normal.

• A. Gasket
• B. Packing
• C. Seal
• D. Bearing

Answer: (B)

Packing rings placed in a stuffing box around a pump shaft form the seal that controls leakage as the shaft turns. The gland compresses the packing so it fills the gaps between the shaft and the box, creating a dynamic seal that allows rotation while limiting fluid escape. A small, steady drip is normal—about one drop per second—because the packing can’t be perfectly watertight at a moving interface, and the drip helps lubricate and cool the packing and purge contaminants. If leakage becomes excessive, the packing may be worn or the gland may be too loose; if leakage stops entirely, the gland is likely over-tightened, which can wear the shaft and packing. Gaskets seal static joints like flanges, seals refer to other types of shaft seals such as mechanical seals, and bearings are involved in supporting the shaft rather than sealing it.