Accro-Seal, Vicksburg, Mich., uses Teflon PTFE fluoropolymer resin from DuPont, Wilmington, Del., to mold the rings for its new pump-shaft sealing system, called Accroseal PLE. The PLE system consists of four sealing rings. Two of them create a seal by wedging together to force one ring against the shaft and the other against the stuffing box. The other two rings are flat back-up rings that hold puttylike packing in place.
The injectable packing compound contains particles of Teflon PTFE that reduce friction and eliminate the need to flush fluid through the packing for cooling and lubrication. “The built-in lubrication of Teflon PTFE helps the PLE system last three times as long as conventional packing while reducing shaft wear,” said Joe Messer, president of Accro-Seal.
Another maintenance-saving advantage of the system is that workers can replenish the material while equipment is running by injecting additional packing through the stuffing-box flush port. The compound can be used in any stuffing box, making it more versatile than conventional woven packings and mechanical seals that must be sized.
Teflon PTFE resists almost all chemicals, so the system can work in industrial environments ranging from chemical processing and petroleum refining to paper mills and other industries using rotating-shaft equipment.