PATENTS

May 2013 Sealing Technology13

Energised seal assembly for a rotary control valve

Applicant: Fisher Controls International Llc, USAThe bellows energised seal assembly described by this patent includes a seal body, a main seal that is capable of sliding axially within the seal body and a bellows that is connected to the seal body and the main seal. The bellows both biases the main seal and provides a seal between the body and the main seal.Patent number: WO/2013/009673Inventors: S.W. Anderson and T.D. GrabauPublication date: 17 January 2013

Device for hermetically sealing a valve stem

Applicant: NOK Corp, JapanThe purpose of this invention is to provide a device for hermetically sealing a valve stem. It is designed to circumvent the problem of the valve-stem seal becoming detached from the valve-stem guide. The seal is provided with a cylindrical metallic ring, held on the outer periphery of the valve-stem guide, and a seal lip is formed inte-grally on one end side of the metallic ring. Made of a rubbery material, it slides with the valve stem in an airtight manner. The valve-stem seal is fixed to the valve-stem guide. A stop ring is fitted into, and held between, the cylindrical inner peripheral surface of the metallic ring and a circular trun-cated, cone-shaped surface that increases in diam-eter towards the seal lip. This surface is formed on the outer peripheral surface of the valve-stem guide. The stop ring has a cut part, and a means is provided for limiting movement in the axial direction of the stop ring on the other side of the metallic ring.

Patent number: WO/2013/008348Inventors: Y. Hamaya and K. HamamtoPublication date: 17 January 2013

Window seal with rinsing-water systemApplicant: Saint-Gobain Glass France, FranceThis invention relates to a method for produc-ing a window seal that includes a rinsing-water system. According to this patent, a strip (1) that consists of a profiled body (1a) contains a continuous body channel (3). A lip (1b) is connected to this profiled body. A lip opening (2) and a connecting channel (4) between the lip opening (2) and the profiled body channel (3) are pierced. The obtained profiled strip is extruded onto a window (5), and the profiled body channel (3) is connected to a hose for the rinsing-water system.Patent number: WO/2013/007503 Inventor: M. GeradsPublication date: 17 January 2013

Method for producing a leak-tight seal between components of a fuel cell

Applicant: Helion, FranceThis patent provides details of a method for producing a leak-tight seal between stacked components of a fuel cell. It involves a series of steps. First, a non-polymerised ‘‘poly-merisable’’ seal is deposited on a leak-tight land of at least one of the components. The material is partially polymerised at the surface so as to form a surface skin on the seal. The seal is then shaped using a calibra-tion mould. After the mould is removed the sealing material is completely polymerised. This method can be applied, in particular, to proton-exchange membrane and solid oxide fuel cells.

Patent number: WO/2013/007649 Inventor: C. QuintieriPublication date: 17 January 2013

Seal for a valve shaft

Applicant: Mitsubishi Electric Corp, Japan This seal member (10) – for a valve – has a structure which consists of a carbon material that is packed into the framework of a stainless steel mesh. Its design aims to suppress the leak-age of fluid around the valve-shaft seal struc-ture. It has an annular flange, which engages a recess formed as a stepped part (7) along the inner wall surface of a through-hole (4), and a press-fitted plate (8). A tubular part protrudes from the flange part (11) so as to taper in the direction of the fluid passage. A sliding part (13) makes contact with the outer circumfer-ential surface of the valve shaft (6) at the inner circumferential surface side of the tip of the tubular part (12).Patent number: WO/2013/008268 Inventors: K. Takai, S. Hasegawa and M. YokoyamaPublication date: 17 January 2013

Sealing structure based on a metal gasket

Applicant: NOK Corp, JapanThis invention relates to a sealing structure that makes use of a metal gasket. The struc-ture is devoid of a gap in which salt water is liable to accumulate (between the gasket and a casing). This means that corrosion of the cas-ing, caused by pools of salt water, is less likely to occur, and the sealing function is main-tained over a long period. In order to achieve this purpose, a single, metal gasket is disposed between a pair of casings. The gasket is

A cross-sectional side-view of the seal assembly in accordance with patent WO/2013/009479. This figure illustrates an ‘‘eccentricity tolerant’’ valve-stem seal assem-bly (40) that comprises an annular seal having upper, flexible middle and lower elastomeric portions (44, 46 & 48, respectively).

This invention relates to a method for producing a window seal that includes a rinsing-water system. Patent WO/2013/007503 has further details.

Patent WO/2013/008268 provides details of a shaft seal for a valve, which has been developed to curb leakage.

PATENTS

14Sealing Technology May 2013

provided with an external planar peripheral part, and beading formed upright from the internal peripheral end-part of the external peripheral part. This beading is in contact with one of the casings, and the external peripheral part is positioned so as to be in contact with the other casing. When the gasket is pressed by the pair of casings, the beading deforms elastically so that its height is reduced and the external peripheral part also deforms elastically. At this stage the distal end of the external peripheral part is in contact with one of the casings, thereby providing a structure devoid of any gap in which salt water is liable to pool.Patent number: WO/2013/008511Inventors: K. Aihara, S. Nakaoka, M. Ito, I. Tanji, T. Anzai and S. TomaPublication date: 17 January 2013

High-pressure tie-back receptacle and seal assembly

Applicant: Halliburton Energy Services Inc, USAA tie-back assembly, and methods of using it, form the subject of this patent. In one method described, the tie-back seal mandrel is inserted into a receptacle. Both the inner surface of this receptacle and the outer sur-face of the seal mandrel are tapered to make contact with each other when mated. An assembly forms an annular seal between the tapered surfaces when the mandrel is inserted into the receptacle. Preferably, the assembly has a burst seal and a collapsible seal, car-ried on one of the tapered surfaces, and are spaced apart longitudinally. These seals are positioned at locations along the tapered surfaces to provide adequate wall thickness for support under pressure. Hydrostatic fluid in the well-bore increases the force necessary to withdraw the seal mandrel by creating a low-pressure zone between the seals that are spaced apart.Patent number: WO/2013/013147 Inventor: B. WatsonPublication date: 24 January 2013

Low-friction seal for bearings

Applicant: Roller Bearing Company of America Inc, USAThis disclosure relates generally to a seal for a bearing, but more specifically to a low-friction material that is coupled to the seal, which facilitates movement of bearing com-ponents relative to one another.Patent number: WO/2013/013005Inventors: J. Voisine and B. SmithPublication date: 24 January 2013

Ready-to-use gasket

Applicant: Henkel Ag & Co Kgaa, GermanyThe gasket described comprises a carrier; an adhesive layer on each side of this carrier; and a releasing layer, covering each adhesive layer. The adhesive layers are cured upon assembly of the gasket. Essentially, this cre-ates a ready-to-use gasket. Sealing the gap between two mating surfaces, it combines the advantages of both solid and liquid gaskets, and can be handled easily on assembly lines, claim the inventors.Patent number: WO/2013/010497 Inventors: V. Kadam, Y.A. Gan, J. Kompala, H. Yin, P. Wrobel, S. Attarwala, G.W. Rossier and I. PradhyumnaPublication date: 24 January 2013

Method for determining when a critical film thickness will be reached in a grease-lubricated sealApplicant: Aktiebolaget SKF, SwedenThe main objective of this invention is to provide a method for determining a time (tc) at which an oil film – separating a sliding contact interface (130) between a counterface and an axial lip (115) of a seal – will reach a critical thickness. One part of the axial lip and counterface is provided on a rotational part (125) of the seal, while the other part of the axial lip and the counterface is provided on a non-rotational part (110) of the seal. Furthermore, the seal is lubricated by grease and the oil film is formed by base oil, which bleeds from a grease reservoir (140) on the rotational part of the seal and flows towards the contact interface (130) under the action of centrifugal force. According to this patent, the method involves determining the speed of the rotational part of the seal; determining the viscosity of the base oil; and determining tc based on the rotational speed, the viscosity of the base oil, cross-sectional area of the grease reservoir and diameter of the contact inter-face. The accompanying figure shows a cross-section of part of the grease-lubricated bearing seal. The seal (100) in the depicted example consists of a metal casing (105), to which an elastomeric seal body (110) is bonded, and a slinger (120). The elastomeric seal body is composed of an axial lip (115), which is in contact with an axial counterface on a radially extending flange part (125) of the slinger. The elastomeric seal body has a radial lip (117), which contacts the radial counterface on an axially extending cylindrical part (127) of the slinger. This invention is concerned with

the axial sealing contact between the axial lip and the slinger flange (the contact region is highlighted in the figure by the outlined box (130)). The grease reservoir is denoted by the other box (140). The oil feed to and oil loss from the sealing contact is simulated to pre-dict the film thickness inside the sealing con-tact (130). The oil loss from the contact takes place because of the natural pumping action of the seal and centrifugal force acting on the oil film in a gap between the axial lip and the slinger flange.Patent number: WO/2013/011086Inventors: P. Baart and M. van ZoelenPublication date: 24 January 2013

Flat seal

Applicant: Reinz-Dichtungs GmbH, GermanyThis invention relates to a flat seal, such as the type that is used in the manufacture of motor vehicles. For example, it can be used as a seal in the exhaust tract of an internal combustion engine, as a cylinder-head gasket, or also as a control plate in a hydraulic system. Hydraulic system control plates – such as transmission control plates – always require the use of a seal in addition to, and simultaneously with, a means of fluid control.Patent number: WO/2013/011132 Inventors: G. Egloff, K. Höhe, A. Gütermann and M. PendzialekPublication date: 24 January 2013

Filter seal

Applicant: Perry Equipment Corp, USAThe filter element described by this patent has an end-cap provided with a seal that can better accommodate non-round holes. The

A cross-section of part of the grease-lubricated bearing seal apparatus that is used to determine when the critical thick-ness of an oil film will be reached. Patent WO/2013/011086 provides full details of the method.