PATENTS Ladder seal system for a gas-turbine engine Applicant: United Technologies Corp, USA A sealing system for a gas-turbine engine forms the subject of this patent. It includes an arcuate, first ladder seal segment that has a central portion; an upstream flange adjoining the central portion; a downstream flange adjoining the central portion, but positioned opposite the upstream flange, and a plurality of openings. The upstream flange is arranged at an angle u, greater than 0°, but less than 90° relative to a given tangential plane, whilst the downstream flange is arranged at an angle o, greater than 0°, but less than 90° relative to the given tangential plane. Patent number: WO/2013/181389 Inventor: K.P. Boyington Publication date: 5 December 2013
VIG window unit with reduced seal height variation Applicant: Guardian Industries Corp, USA This patent provides details of a vacuuminsulated glass (VIG) window assembly and method for making it. According to the patent, a variation in the final edge seal height is 0.20 mm or less, but preferably about 0.15 mm or less. Controlling this variation in the final edge seal height substantially reduces breakage of the glass substrates of the VIG window assembly during the vacuum “pump-down” of the cavity between the glass substrates, say the inventors. The edge seal height variation may be governed, for example, by controlling the initial dispensing of green frit material, and by controlling temperature variations and cycle times during firing. Patent number: WO/2013/180998 Inventors: T.A. Dennis and A.W. Pantke Publication date: 5 December 2013
Fluid, under pressure (36), enters the joint via a “crevice” (32) on the left-hand side. The right-hand crevice (37) is contiguous with the portion of the vessel volume that is at a low pressure, or a vacuum, and must remain free of molecules of the pressurised fluid. In this example, the O-ring (30), made from an elastomeric material, is coated with a metal coating (39) – applied to its interior surface (33). The joint surface (35) has an O-ring groove (40). This groove is designed to initially squeeze the O-ring such that its outer surface elastomer initiates a seal against the upper joint surface (31) and the O-ring groove bottom (34). The metal coating (39) – of O-ring’s interior surface (33) – creates a seal at the joint surface (31) and O-ring groove bottom (34). When fluid pressure (36) is applied from the left, the elastomer acts as a very viscous fluid, conveying the pressure (of the pressurised fluid) to the bulk of the elastomeric material of the O-ring and joint surface and O-ring groove bottom. In addition, the fluid pressure enhances the secondary seal between the metal coating (39) and the joint surface (31) and O-ring groove bottom (34), and establishes a seal against the O-ring groove side (38). Optionally, the seal can be made more effective with increasing pressure differences, reaching the limit of enhancement when the elastomer is extruded into the right crevice (37). The thin metal coating (39) – forming the seal with the joint surface (31), O-ring groove bottom (34) and O-ring groove side (38) – inhibits the diffusion of molecules of the pressurised fluid (and/or any remaining gases in the elastomer itself ) and/or transmission of photons. The scope of gases (and/or wavelengths of photons) that are blocked depends on the nature and thickness of the metal from which the coating (39) is made. Patent number: WO/2013/184231 Inventors: G.H. Biallas and J.R. Boyce Publication date: 12 December 2013
Sealing assembly for a compressor’s reciprocating piston Applicant: Hoerbiger Kompressortechnik Holding GmbH, Austria This invention relates to an arrangement for sealing a piston rod that forms part of a reciprocating compressor. A first and second sealing element are described. These are arranged axially and are spaced apart in a recess of the sealing arrangement. According to the patent, a stationary sealing medium is provided at a pressure that is greater than that to be sealed. The sealing elements are arranged by the pressure of the sealing medium on each axial end of the recess and on the piston rod. Circulation of the sealing medium through the recess is accomplished without impairing the sealing function, in order to ensure that the temperature of the medium is maintained within an acceptable range. Patent number: WO/2013/182456 Inventors: C. Hold, T. Lindner-Silwester, C. Kernbichler and B. Spiegl Publication date: 12 December 2013
Door seal for a refrigerator Applicants: Haier Group Corp and Qingdao Haier Joint Stock Co Ltd – China A seal is located between a refrigerator’s housing body and its door for sealing the gap that is formed between them. The main object of this invention is to create a refrigerator door that has an enhanced sealing effect. The door seal is arranged between the door liner of the refrigerator and a liner of the refrigerator, and includes a “foot” (6) for mounting the door seal on the door liner and an “air bag” (4) that is connected to the mounting foot. A strutting piece (5) is formed on the inner wall of the air bag (4) and extends towards the side of the mounting
Anti-diffusion metal-coated O-ring Applicant: Jefferson Science Associates Llc, USA A method is described for inhibiting diffusion of gases and/or transmission of photons through elastomeric seals. Also discussed is an elastomeric seal that is partly coated with a compatibly deformable, malleable metal coating. The method involves creating an elastomeric seal and applying the coating to part of its surface. The accompanying figure shows a cross-sectional schematic diagram of an exemplary embodiment of the O-ring (30) – in use – that has been developed. The sealed joint between joint surface 31 and 35 is an exemplary sealed joint in a vessel or pipe.
May 2014
A schematic cross-sectional representation of an embodiment of the coated O-ring, detailed by patent WO/2013/184231, whilst it is in use and subjected to applied pressure.
Sealing Technology
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PATENTS foot. Because the strutting piece (5) is formed on the inner wall of the air bag, pressure to the door seal can be buffered and balanced, and a rebound of the door body of the refrigerator can be avoided, say the inventors. Patent number: WO/2013/181917 Inventors: X. Ji, B. Fei, G. Li and J. Fang Publication date: 12 December 2013
Patent WO/2013/181917 provides details of a door seal for a refrigerator. It incorporates an “air bag” (4) that is connected to the mounting foot (6). This design ensures that a rebound of the door body of the refrigerator is avoided.
Threaded coupling for steel pipe Applicants: Nippon Steel & Sumitomo Metal Corp, Japan; and Vallourec Oil and Gas France, France This threaded coupling for a steel pipe is formed from a pin and a box, each equipped with a contact surface that has an unthreaded metal contact part which includes a seal part, and has a threaded part. An ultravioletcurable resin film is formed on the contact surface of the pin and/or the box, whilst an acrylic silicone resin film is formed on at least a portion of the surface of the ultraviolet-curable resin film. Patent number: WO/2013/183634 Inventors: M. Sasaki, K. Sumitani and K. Goto Publication date: 12 December 2013
Fuel-cell gas diffusion layer with moulded-on seal Applicant: United Technologies Corp, USA An exemplary fuel-cell component discussed in this patent includes a generally planar, porous gas diffusion layer. A thermoplastic material at least partially impregnates a selected portion of the gas diffusion layer. A seal member is moulded onto the portion of the gas diffusion layer that includes the thermoplastic material. Patent number: WO/2013/184122 Inventor: T. Skiba Publication date: 12 December 2013 14
Sealing Technology
Radial shaft seal and assembly Applicant: Federal-Mogul Corp, USA A radial shaft seal and assembly have been developed and form the subject of this patent. The seal has an annular mounting portion to which is bonded a seal body. The latter extends to a seal lip, located between an oil-side end and a free air-side end. An annular bridge extends between the seal lip and a central portion of the seal body. A primary dust lip extends from the air-side end and has an annular rib configured for sealed abutment with the running surface of a shaft. This rib has at least one vent. An auxiliary dust lip extends from the central portion of the seal body to a free end configured for sealed abutment with the shaft. The free end of the auxiliary dust lip has at least one vent spaced circumferentially from the vent in the annular rib. Patent number: WO/2013/184611 Inventor: B.R. Sedlar Publication date: 12 December 2013
typical failsafe operation that is well known in the art. The flapper (18) is mounted to the shaft (24) so that it can pivot, for rotation to the open position when the flow tube is pushed towards the flapper as the flow tube continues to advance and places the flapper behind it in the fully open position. Upon loss of control pressure, or removal of control pressure, the closure spring pushes on the operating piston, which moves in tandem with the flow tube (22) – retracting the flow tube. This enables the flapper to close using potential energy in a coiled spring, mounted around shaft (24), that was wound to develop the potential energy as a result of the flapper opening. With the flow tube retracted the spring on shaft urges the flapper against the seat (16). Patent number: WO/2013/184737 Inventors: R.J. Dyer, T.S. Myerley, W.A. Miller, M.P. Presley and M.L. Hair Publication date: 12 December 2013
Curved flapper seal with stepped intermediate surface Applicant: Baker Hughes Inc, USA This invention concerns subsurface safety valves, but more specifically those valves with curved flappers that need to seal against large and small pressure differentials – using a flapper edge treatment to enhance retention of the seal in the sealing position. A recess is provided at the periphery of the flapper so that a corner, which defines this recess, engages an O-ring seal in a seat for the flapper. A reduced contact area of the flapper on the O-ring seal results in increased pressure over the actual contact area. The pressure applied over the contact area also distorts the O-ring. The O-ring is not restrained because of the presence of the recess moving out of the surrounding O-ring groove so that the corner on the flapper pinches the O-ring that is now partly in and partly extends from its surrounding groove. Sealing is obtained at lower differential pressures and the O-ring is effectively fixed as a result of the “pinch effect” of the corner on the flapper. The accompanying figures illustrate an outer housing (10) with a flapper seat assembly (12) that has, at its lower end, a valve body (14) which has a seat (16) at its lower end. The flapper (18) has an undulating edge (20) that conforms to the shape of the seat. A flow tube (22) is driven axially in a known manner using a control line (or control lines) that actuates a piston which is connected to the flow tube (22) for movement in a downward direction against the flapper. The flow tube is returned with a return spring on loss (or removal) of pressure for a
A section view of an assembly of the curved flapper and seat showing the recessed edge on the flapper (18) that is described by patent WO/2013/184737. In an effort to enhance the seal that is needed at low pressure differentials, this design provides a recess in the flapper, preferably at its periphery, such that only partial contact with the O-ring seal is obtained. This partial contact displaces part of the O-ring (out of the groove in the seat). In this way an edge of the recess digs into the O-ring seal to compress an extending portion of it against the edge of the groove for sealing in low differential pressure environments.
May 2014