Packing

Pump packing is a traditional sealing method that uses compressed rings of flexible material to control leakage around a pump's rotating shaft. These braided rings—typically made from materials like graphite, PTFE, aramid fibers, or impregnated cotton—are inserted into the stuffing box and compressed by a gland follower to create a seal against the shaft. Unlike mechanical seals, pump packing is designed to allow a controlled amount of leakage, which provides necessary lubrication and cooling for the packing material and shaft. While packing is less expensive initially and can be easier to install or replace in the field, it generally requires more maintenance, causes greater shaft wear, and consumes more power due to friction. Despite these drawbacks, pump packing remains valuable in applications where occasional leakage is acceptable, budget constraints exist, or where high-abrasive media would quickly damage mechanical seals.