An apparatus and method is described for providing a water impenetrable barrier between an underground duct and an access opening. The apparatus is particularly well suited to cover a secondary opening in a corrugated containment sump of an underground storage tank or the manway of a sanitary sewer, catch basin or other manhole system. The apparatus includes a cover, inflatable seal and a tank of compressed nitrogen to inflate the seal. When sealed to the access opening, the cover restricts the inflow of water or other debris into the interior of the underground duct and nitrogen may be released into the sealed access to reduce corrosion of components contained within the access.

An apparatus and method is described for providing a water impenetrable barrier between an underground duct and an access opening. The apparatus is particularly well suited to cover a secondary opening in a corrugated containment sump of an underground storage tank or the manway of a sanitary sewer, catch basin or other manhole system. The apparatus includes a cover, inflatable seal and a tank of compressed nitrogen to inflate the seal. When sealed to the access opening, the cover restricts the inflow of water or other debris into the interior of the underground duct and nitrogen may be released into the sealed access to reduce corrosion of components contained within the access.

The invention relates to a non-crosslinked natural rubber latex composition for an inflatable stopper comprising a homogeneous mixture of: a) natural rubber latex; b) a surfactant; c) an amine based chemical antiozonant; d) possibly ammonia and preferably e) single or double wall electrically conductive nanotubes. The invention furthermore relates to an ozone resistant inflatable stopper comprising non-crosslinked natural rubber latex and fiber reinforcement, the rubber having an ozone resistance according to ISO 1431/1 at 50 pphm concentration ozone at 232 C., for the time frame of 48 hours, atmospheric humidity of 55% and strain static exposure of 20% and preferably a surface resistivity lower than 100 G according to DIN EN 60079-32-2 and DVGW G 5621-3 (VP) measured at 1000 V and a maximum relative humidity of 30%.

A pipeline pigging element (10) that changes its size in an axial and a radial direction as a function of applied pipeline pressure. The pigging element includes at least two circumferential zones (13, 15) having different section modulus than one another, each of the zones changing at different rates from one another between an uninflated and an inflated state at the applied pipeline pressure. The pigging element reacts to changes in pipe geometry, having a first length and a first diameter at a first applied pipeline pressure and a second length and a second diameter different than the first at a second applied pipeline pressure. As the pigging element wears, it becomes easier to inflate at the applied pressure and sealing contact with the pipe wall remains substantially unaffected. No onboard pumps or fluid circuits are required to inflate the pigging element.

A pipeline pigging element (10) that changes its size in an axial and a radial direction as a function of applied pipeline pressure. The pigging element includes at least two circumferential zones (13, 15) having different section modulus than one another, each of the zones changing at different rates from one another between an uninflated and an inflated state at the applied pipeline pressure. The pigging element reacts to changes in pipe geometry, having a first length and a first diameter at a first applied pipeline pressure and a second length and a second diameter different than the first at a second applied pipeline pressure. As the pigging element wears, it becomes easier to inflate at the applied pressure and sealing contact with the pipe wall remains substantially unaffected. No onboard pumps or fluid circuits are required to inflate the pigging element.

Methods and apparatus are provided for repairing a damaged area within a cored passage of a component. The method includes providing a repair tool that has a support portion, a leading portion extending from a first end of the support portion, and a trailing portion extending from a second end of the support portion. The leading portion of the repair tool is inserted into a first opening of the cored passage, and is threaded through the cored passage until the support portion is positioned at the damaged area within the cored passage. A restoration activity is performed on the damaged area as the support portion supports the cored passage proximate to the damaged area. Upon completion of the restoration activity, the repair tool is removed from the cored passage.

A method for isolating a water valve for repair or replacement includes closing the valve and thereafter replacing an outlet pipe with an adapter pipe. An expandable plug is used to seal the adapter pipe, after which the valve is opened and an air tube having a bladder on an end thereof is inserted through the valve and expanded to seal the inlet pipe. Thereafter, the stem assembly of the valve or the entire valve itself may be removed for simple replacement of the sealing washer or total replacement of the valve. The apparatus for practicing the method, and including the expandable plug, inflatable bladder, and necessary tubing, plug actuator, and air valve are presented.

A modular plug for installation into large diameter pipelines that provides a reliable and secure seal within the pipeline to be serviced thereby increasing the safety of the people working on the secured side of the plug. The plug is modular in construction and suited for easy installation within large pipelines. The plug is generally formed as a large circular plate formed from modular sections. Along the division lines the plug pieces include grooves and a gasket therein. Reinforcing jacks extend outwardly from the plug and exert pressure against the pipeline to retain the plug geometry and position. Also, around the periphery of the plug is shown an inflatable rubber seal.

A modular plug for installation into large diameter pipelines that provides a reliable and secure seal within the pipeline to be serviced thereby increasing the safety of the people working on the secured side of the plug. The plug is modular in construction and suited for easy installation within large pipelines. The plug is generally formed as a large circular plate formed from modular sections. Along the division lines the plug pieces include grooves and a gasket therein. Reinforcing jacks extend outwardly from the plug and exert pressure against the pipeline to retain the plug geometry and position. Also, around the periphery of the plug is shown an inflatable rubber seal.

The present invention relates to an expandable plug structure for use in high pressure applications. The expandable plugs, such as pneumatic plugs, are preferably constructed of a multi-layered, reinforced elastomeric cylindrical body, i.e., of reinforced natural rubber, and having an inflator member at one end. The multi-layers include various rubber layers, rubber coated aramid, which subsequent to vulcanization provides a unitary plug with shoulders that resist delamination. The cylindrical body may incorporate metal end plates as well as end plate weldment structures which cooperate with a high pressure flow-through conduit which allows the completed high pressure test plug to simultaneously seal a pipeline and to direct fluid therethrough. The high pressure plug obtains its strength in part based upon high frictional resistance forces generated by the external rubber layer(s), and further by the manner in which the external rubber layer8s) are molded into the metallic structures in the plug.