Abstract: A mechanical packing braided such that a number of angled recesses or projections at predetermined intervals are formed in the surface of the braid adjacent a rotating shaft, the recesses or projections causing a deflecting hydrodynamic force on the fluid film between the packing and shaft such that leakage of the fluid from under the packing set is reduced when compared to normally braided packing under the same conditions. When constructed from yarns suitable for very low seal water requirements, the rejective “pumpback” force on the fluid film is sufficient to reduce the leakage of seal water to zero so that exfoliated graphite packing which normally has a 95% reliability when running dry can be given a 99.5% reliability. In one troublesome scenario, th subject packing operates to stop leakage due to pressure surges so that water which would ordinarily leak out even with the use of yarns having exfoliated graphite fibers is contained.

Abstract: A self-adjusting interlocking throat bushing is provided in which mating concentric bushing rings are provided with an interlocking annular slot in the outer bushing ring and an annular ridge at the periphery of the inner bushing ring to hold the two rings in axial alignment when bushing is installed and the packing gland is tightened to compress the packing ring between the gland and the bushing. The annular slot/ridge structure prevents canting of the parts of throat bushing during packing ring compression thereby eliminating packing extrusion between the shaft and the annulus of the bushing. Before compression, the concentric rings are held together in alignment so that the bottom ring cannot drop out of its proper position prior to compression. After compression, the locking structure comprising the slot and ridge structure results in the bushing being compressed evenly about the shaft, thereby to eliminate misalignment and shaft sleeve wear.

Abstract: A system for reducing packing ring spin and opening up of the joints formed by the ends of a packing ring during break-in of trapezoidally-shaped mechanical braided packing involves utilization of additional warp yarns within the sides of the packing. These additional warp yarns bulge the packing at the sides of the packing above its horizontal centerline such that the outer portion of the packing is provided with a solid rectangular cross section. The solid section increases frictional contact between the rings and the stuffing box and between the rings themselves to eliminate packing ring spin. When the packing is wrapped around a shaft the bulging sides become flat for secure elongated anti-spin contact both between the packing rings and between the end ring and the bottom of the stuffing box.

Abstract: A universal seal cage lantern ring (USCLR) is provided with a slotted land type structure on both sides of a flexible central web, with the USCLR being constructed in a continuous undefined length, so that lantern rings can be cut to size therefrom, with the USCLR being adapted to wrap around a shaft so as to form a single complete ring around any given size shaft for which it is cut. The structure resembles an I-beam in which the I-beam flanges have been transversely slotted on both sides of the central web. When used for small diameter shafts, this structure prevents fracture or snapping of the ring due to the flexibility of the central web and the slots between lands on both sides of the ring.

Abstract: Edge-reinforced packing is provided for steam service, with wire-reinforced secondary yarns on carriers driven along one or more diagonal tracks of a braiding machine to provide edge-reinforcing which reduces valve stem abrasion while providing sufficient resistance to high pressure, high temperature steam leakage. Wire-reinforcing only the edges of the packing minimizes the amount of reinforcing wire necessary to counteract high pressure steam and thus minimizes valve stem wear. An offset, alternating braid embodiment further reduces wire usage at the packing edges, while at the same time providing complete circumferential reinforced sealing around the valve stem. In cases where the offset braiding results in voids in the steam barrier produced by the reinforced braid, keystone-resisting technology corrects this problem. In one embodiment, the packing is a non-asbestos packing which eliminates both hardening and packing disintegration normally associated with so called "plastic-core" packings.

Abstract: A braided mechanical compression packing including relatively low and high-strength yarns is provided with greater mechanical strength along a given diagonal direction to provide a reinforced corner by providing the higher strength yarn along only one diagonal track of the braider. This reduces extrusion of the packing from the confines of the stuffing box in which it has been sequentially installed; produces a packing with rectilinear non-symmetry having directionally different friction, for instance, to facilitate gravity return of a hydraulic ram; and lowers operating friction by reducing the overall amount of high-strength yarn in the packing braid.

Abstract: A non-symmetrical construction of braided mechanical compression packing which does not undergo undesired deformation when placed in use. This non-symmetry of construction results in longer packing life and reduced shaft wear when used to prevent leakage about rotating shafts.

Abstract: A non-symmetrical construction of braided mechanical compression packing which includes warp yarns removed from the inner corners to prevent "popping" of these yarns during manufacture or when the packing is wrapped about a shaft. Additionally, a number of embodiments involving interior space filled with varying numbers of warp yarns at different positions produce an optimal warp density gradient in the finished braid, such that the braid has a more regular trapezoidal cross-section prior to being wound about a shaft, with the higher density occurring at the outside of the packing and tapered in density toward the inside of the packing. This non-symmetry of construction results in longer packing life and reduced shaft wear when used to prevent leakage about rotating shafts.

Abstract: A non-symmetrical construction of braided mechanical compression packing which does not undergo undesired deformation when placed in use. This non-symmetry of construction results in longer packing life and reduced shaft wear when used to prevent leakage about rotating shafts.