Pipe plug and remote installation equipment therefor

In combination with the steam line of the reactor vessel of a boiling water reactor, the reactor vessel having an open top and an upper edge, and having isolation valves in said steam line to be tested under pressure, said steam line having an entrance portion with an internal side wall surface, a plug device in said entrance portion, said plug device comprising, in combination, a plug member made of resilient material which, when compressed in one direction, expands in a direction transverse to said one direction, said plug member being elongated in said one direction and having an external surface with a shape generally conforming to the shape of said internal side wall surface, a pair of relatively rigid end members, each being positioned at one end of said plug member, compression means comprising a plurality of axial compression rods spaced circumferentially adjacent said external surface of said plug member for urging said end members towards one another so as to compress said plug member in said one direction, and thus cause it to engage and form a seal with said internal side wall surface, and gripper means to engage said internal side wall surface to help hold said plug member in said entrance portion, said entrance portion being substantially horizontal, and including support means for extending above said upper edge of said reactor vessel for supporting said plug in a substantially horizontal alignment for insertion into said entrance portion at a location spaced downwardly from said upper edge, said support means including a support member secured to and extending outwardly from one of said end members.

In combination with the steam line of the reactor vessel of a boiling water reactor, the reactor vessel having an open top and an upper edge, and having isolation valves in said steam line to be tested under pressure, said steam line having an entrance portion with an internal side wall surface, a plug device in said entrance portion, said plug device comprising, in combination, a plug member made of resilient material which, when compressed in one direction, expands in a direction transverse to said one direction, said plug member being elongated in said one direction and having an external surface with a shape generally conforming to the shape of said internal wall surface, a pair of relatively rigid end members, each being positioned at one end of said plug member, compression means comprising a plurality of axial compression rods spaced circumferentially adjacent said external surface of said plug member for urging said end members towards one another so as to compress said plug member in said one direction, and thus cause it to engage and form a seal with said internal side wall surface, and gripper means to engage said internal side wall surface to help hold said plug member in said entrance portion, said compression rods extending between said end members, and including means for moving one of said end members along said rods towards and away from the other of said end members, stop members on said rods, at lease one release member for bearing against said one end member and said stop members, said release member being movable to a release position in which it does not engage said stop members and relieves the compressive forces previously applied to said plug member by said compression means.

In combination with the steam line of the reactor vessel of a boiling water reactor, the reactor vessel having an open top and an upper edge, and having isolation valves in said steam line to be tested under pressure, said steam line having an entrance portion with an internal side wall surface, a plug device in said entrance portion, said plug device comprising, in combination, a plug member made of resilient material which, when compressed in one direction, expands in a direction transverse to said one direction, said plug member being elongated in said one direction and having an external surface with a shape generally conforming to the shape of said internal side wall surface, a pair of relatively rigid end members, each being positioned at one end of said plug member, compression means for urging said end members towards one another so as to compress said plug member in said one direction, and thus cause it to engage and form a seal with said internal side wall surface, including remote actuating means for actuating said compression means from a location above said upper edge of said reactor vessel, in which said compression means includes a plurality of threaded, elongated bolts and nuts, said remote actuating means including a driving unit having a plurality of wrenches and at least one motor to drive said wrenches, there being one wrench for each of said nuts, means for holding said wrenches in alignment with said nuts, means for engaging each wrench with one of said nuts, and means for operating said motor, including remote support means for remotely supporting said plug and driving unit in alignment with said pipe for insertion of said plug in said pipe, said remote support means comprising a support member secured to one of said end members, an elongated beam with said driving unit secured thereto at one end, and fastening means for releasably securing said support means to said beam.

In combination with the steam line of the reactor vessel of a boiling water reactor, the reactor vessel having an open top and an upper edge, and having isolation valves in said steam line to be tested under pressure, said steam line having an entrance portion with an internal side wall surface, a plug device in said entrance portion, said plug device comprising, in combination, a plug member made of resilient material which, when compressed in one direction, expands in a direction transverse to said one direction, said plug member being elongated in said one direction and having an external surface with a shape generally conforming to the shape of said internal side wall surface, a pair of relatively rigid end members, each being positioned at one end of said plug member, compression means for urging said end members towards one another so as to compress said plug member in said one direction, and thus cause it to engage and form a seal with said internal side wall surface, including remote indicating means for indicating the degree of compression of said plug member, in which said compression means includes a plurality of axial compression rods spaced circumferentially adjacent said external surface of said plug member, said remote indicating means including a plurality of transducers, one mounted adjacent each of said rods, for detecting the axial compression produced separately by each rod, converting said compression into a signal, and displaying a corresponding indication at a remote location.

In combination with the steam line of the reactor vessel of a boiling water reactor, the reactor vessel having an open top and an upper edge, and having isolation valves in said steam line to be tested under pressure, said steam line having an entrance portion with an internal side wall surface, a plug device in said entrance portion, said plug device comprising, in combination, a plug member made of resilient material which, when compressed in one direction, expands in a direction transverse to said one direction, said plug member being elongated in said one direction and having an external surface with a shape generally conforming to the shape of said internal side wall surface, a pair of relatively rigid end members, each being positioned at one end of said plug member, compression means comprising a plurality of axial compression rods spaced circumferentially adjacent said external surface of said plug member for urging said end members towards one another so as to compress said plug member in said one direction, and thus cause it to engage and form a seal with said internal side wall surface, and gripper means to engage said internal side wall surface to help hold said plug member in said entrance portion, said compression means being adapted to apply a pre-determined holding force to said internal side wall surface to hold said plug in place under dislodging pressure, the dimensions of said plug member being such that the degree of compression of said plug member needed to produce said holding force is limited to a range of from approximately seventy-five percent to approximately ninety percent.

In combination with the steam line of the reactor vessel of a boiling water reactor, the reactor vessel having an open top and an upper edge, and having isolation valves in said stem line to be tested under pressure, said steam line having an entrance portion with an internal side wall surface, a plug device in said entrance portion, said plug device comprising, in combination, a plug member made of resilient material which, when compressed in one direction, expands in a direction transverse to said one direction, said plug member being elongated in said one direction and having an external surface with a shape generally conforming to the shape of said internal side wall surface, a pair of relatively rigid end members, each being positioned at one end of said plug member, compression means comprising a plurality of axial compression rods spaced circumferentially adjacent said external surface of said plug member for urging said end members towards one another so as to compress said plug member in said one direction, and thus cause it to engage and form a seal with said internal side wall surface, and gripper means to engage said internal side wall surface to help hold said plug member in said entrance portion, there being a space between said plug member and said internal side wall surface when said plug member is uncompressed in said one direction, said compression means being adapted to apply a predetermined holding force to said internal side wall surface to hold said plug member in place under dislodging pressure, the amount of compression force required to fill said space is less than approximately twenty percent of the total compression force needed to produce said holding force.