Patents Assigned to Specialist Sealing Limited
  • Patent number: 6131915
    Abstract: A seal 2 for sealing between two opposed and generally parallel surfaces, comprising a support layer 10 for location between the said opposed surfaces and a pair of sealing layers 6, 8 supported on the support layer 10 and projecting beyond an edge 2 of the support layer 10 for effecting a seal between the said opposed surfaces when the said seal 2 is located therebetween.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: October 17, 2000
    Assignee: Specialist Sealing Limited
    Inventor: Terence Peter Nicholson
  • Patent number: 5669612
    Abstract: An API groove seal is a metal ring of cross-section like a capital letter omega arranged so that the tips of its limbs provide the sole contact with the groove base before and after compression. The central or heel region may abut on the outer side wall of the groove. A family of seals for different pressure ratings has a common profile, differing only in respect of the thickness of the limbs.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: September 23, 1997
    Assignee: Specialist Sealing Limited
    Inventor: Terence Peter Nicholson
  • Patent number: 5577742
    Abstract: A valve stem seal comprising a cylindrical stem-sealing membrane and a membrane supporting flange. The membrane has a corrugated profile which defines one or more loop-shaped channels bounded by contact surfaces on a radially inner face and each channel is inclined at 5.degree.-10.degree. with respect to a plane perpendicular to the longitudinal axis. The channels form a labyrinth seal for any fluid leaking along the outer surface of the stem. A support bearing for the stem is provided on the membrane supporting flange.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: November 26, 1996
    Assignee: Specialist Sealing Limited
    Inventors: Terence P. Nicholson, Michael J. C. Tozer
  • Patent number: 5558347
    Abstract: A static seal comprising an envelope of chemically resistant PTFE and a metallic packing ring within the envelope shaped to form cells. The cells may be filled with an inert gas under pressure so that increased loads on the seal may be cushioned.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: September 24, 1996
    Assignee: Specialist Sealing Limited
    Inventor: Terence P. Nicholson
  • Patent number: 5354072
    Abstract: According to a first aspect of the invention a metal sealing ring has a hollow cross section which is open at its radially innermost side and has limbs generally directed towards the radially innermost side. The radially outermost region of the cross section is provided with reinforcement so as to locally increase its hoop strength. According to a second aspect of the invention, a hollow self-energising metal sealing ring and a seating for the sealing ring are provided with complimentary radial cross sectional shapes which cooperate to limit the rotation of the sealing ring cross section when axially compressed.As can be seen in FIG. 11, the surfaces 45 are tangential to the convex arcuate contact lines C, in the relaxed state of the seal ring. During compression these surfaces remain substantially tangential to the regions C, as the limbs flex.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: October 11, 1994
    Assignee: Specialist Sealing Limited
    Inventor: Terence P. Nicholson
  • Patent number: 5240263
    Abstract: A metallic sealing ring which in radial cross-section is hollow and of sinuous profile having axial end faces sinuously curved so as each to define an axially outward facing deep peripheral groove, the interior of the ring profile being in communication with the exterior thereof.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: August 31, 1993
    Assignee: Specialist Sealing Limited
    Inventor: Terence P. Nicholson
  • Patent number: 4915397
    Abstract: A hollow metallic sealing ring of low-load, self-energizing, static kind is characterized in that in radial cross-section it is of modified parabolic form with convergent margins (M) with a radial width, in its relaxed state, which is equal to substantially 7/8ths (0.875) of its maximum length (A) measured in the direction parallel to the axis of the ring.
    Type: Grant
    Filed: June 27, 1986
    Date of Patent: April 10, 1990
    Assignee: Specialist Sealing Limited
    Inventor: Terence P. Nicholson
  • Patent number: 4890816
    Abstract: A metal valve seat for a butterfly valve or ball valve and has the form of an apertured disc with a radially outward part (4A) by which it is securable to a valve body and a radially inward dished part (4B) which projects laterally around the disc aperture. The valve seat is characterized in that the disc part (4B) is formed circumferentially with a plurality of web-connected fingers which have a radially inward surface of varying generative radius. The invention also consists in a butterfly valve or a ball valve incorporating one or a pair of such metal valve seats.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: January 2, 1990
    Assignee: Specialist Sealing Limited
    Inventor: Terence P. Nicholson
  • Patent number: 4832353
    Abstract: A heat safe ring seal comprises a metallic hollow ring (1) of uniform material thickness and radially inwardly facing channel-shaped radial profile. The walls of the channel adjacent their free ends are curved towards each other so as to form axially outwardly facing grooves (1a) which each accommodate and shield a concentric ring (2) of PTFE or elastomeric material.
    Type: Grant
    Filed: June 27, 1988
    Date of Patent: May 23, 1989
    Assignee: 501 Specialist Sealing Limited
    Inventor: Terence P. Nicholson
  • Patent number: 4784397
    Abstract: A hollow metallic sealing ring comprised in radial cross-section of pair of outwardly convex limbs contiguous with a loop formation having at least one straight sided loop, the limbs, from their junctions with the ends of the loop formation being of increasing radius towards their free ends which are straight and substantially parallel.
    Type: Grant
    Filed: November 16, 1987
    Date of Patent: November 15, 1988
    Assignees: Michael J. C. Tozer, Specialist Sealing Limited
    Inventor: Michael J. C. Tozer