Abstract: A contacting mechanical end face seal for use in applications having slow shaft rotational speeds, such as mixers, agitators and reactors, includes at least one seal ring having a face with spiral grooves. Both hydrostatic and hydrodynamic lift characteristics in the seal are utilized to generate and maintain a seal gap having sufficient stiffness to prevent contact of the seal ring faces during operation. Specific characteristics, or combinations of them, include a land to groove ratio between 0.2-0.9, tapered groove surfaces which are inclined from the O.D. toward the dam, groove area to land area ratios greater than 1.5, a stepped groove having a greater depth at the O.D. relative to the depth adjacent the dam, alternating deep and shallow grooves, and groove area to dam area ratio in the interface greater than 1.2.

Abstract: A rotary shaft monitoring seal system includes a seal housing; a seal assembly in the housing for sealingly engaging a rotary shaft to prevent fluid leakage between the shaft and the housing; a monitoring port in the housing; and a detector assembly mounted in the port for sensing conditions in the vicinity of the seal assembly.

Abstract: A mechanical end face seal for sealing between a housing and a relatively rotating shaft which seal includes a pair of relatively rotating annular rings having seal faces in sealing contact with each other to define a seal interface, with one of the rings adapted to be secured to said shaft for rotation therewith, and the other fixed relative to the housing and one being axially movable toward the other. A generally annular flexible metal diaphragm secured between the axially movable ring and either the housing or shaft includes a generally radial disc-like central portion which defines a plurality of annular convolutions formed by protrusions extending in opposite axial directions. The diaphragm is pressed onto a cylindrical surface on the ring at about the center of mass of the ring. The surface includes a coating of a compound including PTFE, grit and a binder.

Abstract: A lip seal for use in low torque, high pressure applications including a rigid retainer, a resilient body essentially covering the retainer and an inner support member. The inner support member provides spacing and orienting functions for the other elements. The inner support member has a radial dimension and outer diameter smaller than the inner diameter of an outer axial wall of the retainer so that a gap is maintained between the retainer and the inner support member under a variety of pressure, torque and shaft deflection conditions. Gap maintaining elements, preferably in the form of axially extending guides, prevent contact between the rigid seal elements. The guides may further comprise nub portions at one end which contain the inner support member in the cavity prior to installation on the shaft.

Abstract: A unitary radial lip seal assembly to provide a fluid tight seal between a shaft and a housing bore through which the shaft extends includes an annular rigid retainer, a resilient body portion secured to the retainer and defining at least one sealing lip to seal against the rotatable shaft and a sleeve bearing member supported by said seal assembly outboard of the sealing lip. In one form the bearing member is rigidly connected to the retainer, in another, it is resiliently mounted to provide shaft vibration dampening. In the latter embodiment, the bearing member includes a radial wall urged into frictional engagement with a radial wall of the resilient body to restrict rotation of the bearing member.

Abstract: A mechanical end face seal for sealing between a housing and a relatively rotating shaft which includes a pair of relatively rotating annular rings having seal faces in sealing contact with each other to define a seal interface. A generally annular flexible metal diaphragm is secured between an axially movable ring and either the housing or shaft in a configuration such that it is placed in tension to achieve a preload or initial closing force upon the seal faces. In one form the seal components are unitized into a single assembly. A retainer is adapted to be disposed in a bore of the housing in surrounding relation to the shaft. The seal rings are disposed intermediate the axial ends of the retainer with the generally annular flexible metal diaphragm secured to one end of the retainer to define one closure wall of the assembly and to capture the ring components within the retainer.

Abstract: A mechanical end face seal of the non-contacting type includes a primary seal ring having a back section, a seal face section and a middle section between the seal face and the back sections, each primary ring section having a radial dimension, defined as the difference between the outermost radius and the innermost radius of said respective section, the radial dimension of the back section being in a ratio relative to said middle section of between about 1.5 to about 3.1, and more preferably of between about 1.9 to about 2.5, and most preferably about 2.0 to about 2.3. Additionally, the mating seal ring includes grooves extending from one seal ring circumference toward the other and terminating adjacent a dam at a radius R.sub.g, it is beneficial to have the boundary between the grooves and the dam have a radius R.sub.g slightly larger or smaller, within about 10%, than the outer radius of the middle section.

Abstract: A double, back to back oriented mechanical end face seal arrangement for use in sealing pumps or other devices used in fluid transfer of toxic or corrosive fluid has an intermediate buffer fluid chamber into which a relatively inert gas, such as nitrogen, is provided for use as a buffer fluid, and is maintained at a pressure which exceeds the process fluid pressure by at least 10 p.s.i. Each seal has a primary ring and a mating ring with gap maintaining means, such as spiral pumping grooves, formed in one of the rings which are shaped and dimensioned to pump the buffer gas through the first seal from the intermediate chamber into the process fluid chamber against the process fluid pressure and through the second seal from the intermediate chamber into the environment external to the housing and sealing area, thus avoiding the escape of the process fluid into the intermediate buffer chamber and thereby to the atmosphere.

Abstract: A secondary seal for use in a high temperature and pressure environment, including only non-elastomeric elements, such as an annular wound spring essentially enclosed on three sides by a polymer cladding. Two lips surround the spring, while permitting an exposed spring section to maintain direct contact with a radial wall surface of a disc which retains the secondary seal disposed annularly around the back face of a seal primary ring. Optional ridges having flat sealing surfaces on one sealing surface of the secondary seal defines a number of discrete annular cells to provide a cascading pressure profile across the sealing surface.

Abstract: A mechanical end face seal of the non-contacting type includes a primary seal ring having a back section, a seal face section and a middle section between the seal face and the back sections, each primary ring section having a radial dimension, defined as the difference between the outermost radius and the innermost radius of said respective section, the radial dimension of the back section being in a ratio relative to said middle section of between about 1.8 to about 2.8, and more preferably of between about 1.9 to about 2.5, and most preferably about 2.0 to about 2.3. Additionally, the mating seal ring includes grooves extending from one seal ring circumference toward the other and terminating adjacent a dam at a radius R.sub.g, it is beneficial to have the boundary between the grooves and the dam have a radius R.sub.g slightly larger or smaller, within about 10%, than the outer radius of the middle section.

Abstract: Improved spiral grooves in a mechanical face seal have plural terminal corners which more evenly distribute the fluid pressure generated within the seal gap into discrete pressure zones which are radially displaced and may also be circumferentially displaced from the other pressure zones generated by the same groove. Alternative embodiments include grooves having surfaces of varying depths wherein each of the plural terminal groove corners is associated with a section of the groove having a surface at a particular depth.

Abstract: A composition of matter for use in tribological applications, such as in mechanical seals, bearings and other sliding or rubbing components, which provides good durability and wear characteristics. The material is used in the "softer" one of two relatively sliding members which are in, or may come into, contact with each other during the relative rotation of one of the member s relative to the other. The material is a carbon or carbonaceous formed material, such as is normally used in the manufacture of a primary seal ring in a mechanical seal, and comprises an additive compound which contains at least one compound from a group consisting of neodymium fluoride, praseodymium fluoride, gadolinium fluoride and lanthanum fluoride.

Abstract: A three-part seal comprising an inboard, an intermediate and an outboard seal and defining two chambers, a mixing chamber between the inboard seal and the intermediate seal and a buffer chamber between the intermediate seal and the outboard seal, provides the capability of zero emissions of a process fluid under pressure in a housing. The process fluid may comprise a toxic or otherwise environmentally hazardous process fluid. A radial bore provides fluid communication between the buffer chamber and a buffer fluid reservoir, for example, a source of nitrogen gas, which is maintained at a pressure, preferably about five to eight psi, over the fluid pressure in the mixing chamber.

Abstract: A seal assembly is mounted on a shaft in sealing relationship to provide a sealed chamber in a housing from which the shaft extends. The seal assembly includes a unitary annular seal body attached to an annular retainer. The seal body includes three radial sealing lips in engagement with the shaft. A primary lip is adjacent the sealed chamber and provides the primary fluid seal. A secondary lip is rearward of the primary lip and keeps the primary lip aligned with the shaft. A rearward lip excludes environmental contaminants from entering the sealed chamber.

Abstract: A seal face of at least one ring used in a non-contacting, gap-type mechanical end face seal having a pattern including an optional dam and an annular grooved area. The annular grooved area has one of several embodiments, including entrance lands which are essentially triangular and have one side contiguous with one circumferential edge of the annular grooved area. These embodiments further include a set of converging boundary sides of the groove to provide a pressure zone effect. Seal face patterns include a contiguous groove around the circumference of the seal face and a series of annular bands comprising a repeating pattern of an essentially triangular groove interposed between two adjacent, but oppositely oriented, lands.

Abstract: A mechanical end face seal having a first seal ring with a generally radially extending sealing face, a second seal ring having a sealing face opposite to and in mating relation with the sealing face of the first seal ring, the second seal ring having a generally radially extending back face removed from and oppositely disposed to said sealing face, the back face including an annular shoulder at the outer diameter defined by an annular axially extending flange which forms an annular section between the flange and the ring outer diameter. The annular section displaces the ring centroid further toward the seal interface and also toward the ring inner diameter, thus minimizing axial rotational and pressure forces acting on the axially movable ring to stabilize the ring. Stabilization of the ring permits balancing the seal to over 80% for dry-running with a gas lubricant at over 300 psig pressure differential and high rotational speeds.

Abstract: A totally split mechanical face seal being installable and replaceable without necessitating breakdown of the shaft and/or housing. The inventive split seal is well suited for replacement of packing or stuffing in heavy duty or inaccessible locations. The inventive seals include a sealing element that seals the primary ring against the shaft and rigidly positions the primary ring in the axial, circumferential and radial directions, and also includes a sealing element which seals the mating ring against the housing and non-rigidly positions the mating ring in the axial direction while simultaneously providing an axial biasing force on the mating ring to provide mating contact of the two rings. For applications where gross displacements of the shaft relative to the housing are expected, a thrust bearing or a connection is made between the mating ring assembly and rotating elements associated with shaft.

Abstract: A mechanical end face seal with a mating ring having a beveled inner diameter extending frusto-conically to the back face. Atmosphere or other fluids located outside of the housing can enter through the frusto-conical opening between the primary ring and the shaft to cool the seal rings during shaft rotation. In a preferred embodiment, a drive collar disposed adjacent the primary ring and attached to the shaft includes a series of cantilever projection portions which rotate in the atmosphere outside the housing to circulate the atmosphere into the frusto-conical space between the beveled inner diameter of the stationary mating ring to provide a fan blade effect.

Abstract: An inner diameter pressurized mechanical end face seal includes at least one seal module with adjacent relatively rotating rings each having a radially extending face confronting the face of the other ring. At least one of the rings, preferably the rotating ring, has plural spiral grooves adjacent to or extending from the inner diameter of the ring whereby the fluid pressure from the inner diameter together with the centrifugal force of the rotating ring expel any fluid leaking from the seal outwardly from the sealed chamber with sufficient force to inhibit contaminants from outboard the seal ring interface area from entering the seal. The structure and material comprising one or both of the rings provides structural integrity to each ring, thereby permitting the inner diameter pressurized seal rings to withstand fluid pressures up to at least as high as 1200 psi. Preferably, the ring material is a composite plastic material, such as polyamide-imide.

Abstract: Improved spiral grooves in a mechanical face seal have plural terminal corners which more evenly distribute the fluid pressure generated within the seal gap into discrete pressure zones which are radially displaced and may also be circumferentially displaced from the other pressure zones generated by the same groove. Alternative embodiments include grooves having surfaces of varying depths wherein each of the plural terminal groove corners is associated with a section of the groove having a surface at a particular depth.