Patents Assigned to Underpressure Engineering Co. Limited
  • Patent number: 5360238
    Abstract: A metal fitting (11) for an end of a plain length of pipe (12) comprises a body (13) with flange means (14) adjacent a first end (15), a gland ring (16) adjacent the other end (17) of the body, a grip ring (18) between the body (13) and the gland ring (16), and screw fasteners (19) for urging the gland ring (16) towards the flange means (14); characterised in that:the body (13) has an integral outer tubular spigot (20) projecting towards the gland ring (16) and a co-axial integral inner tubular spigot (21) having a cylindrical outer surface (22) projecting beyond the free end (23) of the outer tubular spigot (20), the inside (24) of the outer spigot (20) being provided with a frustoconical portion (25) adjacent and converging from that free end;the gland ring (16) has its inside provided with a similar frustoconical portion (26) converging in the opposite direction;and the grip ring (18) is a split ring having external surfaces (27, 28) mating with the frustoconical portions in the body (13) and the gland rin
    Type: Grant
    Filed: April 9, 1993
    Date of Patent: November 1, 1994
    Assignee: Underpressure Engineering Co., Limited
    Inventors: Geoffrey C. Godfrey, David Bassett
  • Patent number: 5297581
    Abstract: Pipeline plugger has a piston (22) on its push-pull rod (16) in a cylinder (23) the lower end (25, 26) of which is sealed to the swivel member (24) in which the push-pull rod is sealingly slidable, the upper end (29) of the cyliner (23) is slidably sealed on the push-pull rod, a vent hole (30) to atmosphere is provided from the cylinder (23) adjacent the swivel seal (15), and a bleed passageway (31) is provided in the push-pull rod from adjacent the plug (18) to just above the piston (22), whereby, when the damper type valve (12) is opened, gas admitted into the chamber (14) is bled through the passageway (31) to above the piston (22), thus applying a downward load on the piston annulus to counterbalance the upward gas load on the push-pull rod (16), so that the plug (18) can then be pushed down easily into the pipe (11) through the valve (12), the branch (13) and the hole (19) in the pipe.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: March 29, 1994
    Assignee: Underpressure Engineering Co. Limited
    Inventor: Geoffrey C. Godfrey