Abstract: A minimum leakage packing system is provided for sealing pump shafts and the like. The packing is manufactured from twisted, exfoliated extruded, pultruded or slit graphite material that is braided, twisted, laid up or otherwise combined to form mechanical packing. A lubricant and/or sealant may be applied to the finished packing. Graphite foil may be applied to the packing for enhanced properties. The packing system preferably consists of a precision wedge set and at least three rings including compressible graphite material, the rings compressed to different percentages of their original heights. The outside rings will have the most compression and the inner ring or rings of the multi-ring assembly the least. All should be compressed less than the maximum amount to permit high conformance to the surface being sealed. The system may have an optional gasket washer following the last ring of compressed graphite material.

Abstract: A minimum leakage packing system is provided for sealing pump shafts and the like. The packing is manufactured from twisted, exfoliated extruded, pultruded or slit graphite material that is braided, twisted, laid up or otherwise combined to form mechanical packing. A lubricant and/or sealant may be applied to the finished packing. Graphite foil may be applied to the packing for enhanced properties. The packing system preferably consists of a precision wedge set and at least three rings including compressible graphite material, the rings compressed to different percentages of their original heights. The outside rings will have the most compression and the inner ring or rings of the multi-ring assembly the least. All should be compressed less than the maximum amount to permit high conformance to the surface being sealed. The system may have an optional gasket washer following the last ring of compressed graphite material.

Abstract: A packing material having improved chemical resistance formed of poly(phenylene) sulfide yarn and polytetrafluoroethylene yarn is provided. Each of the yarns may be treated with PTFE dispersion and, optionally, with graphite. The two yarns may be twisted together or laid-up side-by-side and braided together and the structure may be impregnated with a polytetrafluoroethylene based binder and lubricant. The resulting packing material has improved temperature characteristics, heat transfer characteristics, wear resistance, provides a dense impervious packing and is dimensionally stable in addition to the improved chemical resistance. A packing material prepared from yarns treated only with a PTFE dispersion is especially useful in the paper making industry and for other applications wherein dark colored yarns are not permissible.

Abstract: A packing material comprises glass or other inorganic fibers in combination with organic fibers such as sintered polytetrafluoroethylene (TFE) or other selected fibers with or without an impregnant, a preferred impregnant being a lubricant with a binder. Ceramic fiber or quartz fiber can be substituted for glass fiber. Specific metal disulfides or talc can be substituted for the dispersed graphite and dispersed polytetrafluoroethylene (TFE) can be used as a binder for the lubricant. Aramid, polyethylene, polypropylene, graphite, carbon, vegetable, nylon or rayon fibers or filaments can be substituted for the sintered TFE fiber in combination with inorganic fiber.

Abstract: A low-friction, water- and steam-resistant packing suitable for both static and dynamic applications includes inorganic fiber selected from the group consisting of chemical, electrical, structural and alkali resistant glasses, ceramic, quartz, carbon and graphite materials, and dispersed and dried, but unsintered, polytetrafluoroethylene (TFE). The packing is essentially free of wetting agent and is prepared by combining the inorganic fiber with a TFE dispersion containing a wetting agent and heating the resulting combination to a temperature high enough to decompose the wetting agent but insufficiently high to sinter the particles of the dispersion.

Abstract: A gasket material combines a braided organic fiber sleeve for conformability with a vitreous fiber sleeve for reinforcement thereof. The gasket material is impregnated with polytetrafluoroethylene as a sealant. In another embodiment a sleeve is braided of yarn containing both inorganic and organic fibers, the different fibers being spun or twisted together. The reinforcement provided by the vitreous fiber makes it possible to use the gasket material to retain fluid at higher pressures than is possible with organic fiber alone. Gasket arrangements are disclosed which provide against leakage at the cut ends of the gasket material.Preferred organic fibers are polytetrafluoroethylene and aramid. Preferred vitreous fibers are electrical, structural and chemical grades glass fiber.

Abstract: A gasket material has a resilient core of glass fiber and a jacket of glass or other suitable fiber over said core. The jacket and core may have therebetween an essentially impermeable sheath of a chemically resistant material. The jacket has therein enough polytetrafluoroethylene in dispersed form to prevent flow of liquid therethrough. The core may have enough of the polytetrafluoroethylene dispersion therein to prevent wicking.