Inflatable pipe plug

Claim 1

A molded inflatable pipe plug, including in combination: (a) an assembly comprising, vulcanized together, (1) an inner one-piece rubber member in the shape of a cylinder open at one end and closed by a dome at the other, (2) a first strip of rubber wire cord having unidirectional threads, covering said dome, (3) a second strip of rubber tire cord covering said first strip, and having unidirectional threads running at about 45° with respect to the threads of said first strip, (4) a first sleeve of rubber tire cord having unidirectional threads, covering said cylinder and the strip-covered dome, said first sleeve having a first terminal portion capable of extending beyond said open end and a second terminal portion capable of extending beyond the juncture of said cylinder and dome, said threads lying at about 10° to an axially extending longitudinal line, said second terminal portion being split into several strip-like portions adhered to said dome and said first and second strips, with overlap, (5) a circumferential band of rubber tire cord with unidirectional threads running circumferentially, overlying said first sleeve adjacent to said open end, (6) a second sleeve of rubber tire cord with unidirectional threads, spaced from said open end and covering a portion of said band and a portion of said first sleeve, with its threads lying at about 10° to said longitudinal line in the opposite direction from those of said first sleeve, thereby forming an angle of about 20° with them, said second sleeve having one end substantially co-terminous with that of said second terminal portion and split into several strip-like portions, covering said dome, said first and second strips and the strips of said first sleeve, with overlap, said first terminal portion of said first sleeve being folded back to overlie the full width of said band and a portion of said second sleeve therebeyond, and (7) an outer rubber member shaped generally like said inner rubber member and covering all said strips, (b) an aluminum head having an axially extending tubular portion fitting into the interior of said assembly and against the inner cylindrical surface thereof for a distance somewhat shorter than the width of said band and having an end flange extending radially outwardly, engaging said open end of said assembly and provided with a series of axially extending bolt openings. (c) a molded rubber sleeve longer than said tubular portion firmly secured to the inner wall of said tubular portion and to the inner cylindrical surface of said assembly therebeyond, said head, molded sleeve, and assembly being vulcanized together, (d) an annular gasket over said flange at the exposed face thereof, and (e) a metal cap bolted to said flange of said head, said cap having a central exterior anchor means for securing a cable or chain thereto and inlet fitting means for sending air under pressure into the interior of said plug.

Claim 10

A method for making a molded inflatable pipe plug, comprising the following steps: molding an inner one-piece rubber member in the shape of a cylinder open at one end and closed by a dome at the other, the dome and cylinder being integral with each other, covering said dome snugly with a first strip of sticky rubber tire cord having unidirectional threads, covering said first strip snugly with a second strip of sticky rubber tire cord also having unidirectional threads running at about 45° with respect to the threads of said first strip, covering said cylinder snugly with a first sleeve of sticky rubber tire cord having unidirectional threads, said first sleeve having a first terminal portion extending well beyond said open end and a second terminal portion extending beyond the juncture of said cylinder and dome, said threads lying at about 10° to an axially extending longitudinal line, splitting said second terminal portion into several strip-like portions and covering said dome and said first and second strips snugly therewith, with overlap of the strip-like portions with each other, applying to said cylinder snugly over said first sleeve adjacent to said open end a circumferential band of sticky rubber tire cord with unidirectional threads running circumferentially, covering a portion of said band and a portion of said first sleeve snugly with a second sleeve made from sticky rubber tire cord with unidirectional threads lying at about 10° to said longitudinal line in the opposite direction from those of said first sleeve, thereby forming an angle of about 20° with them, said second sleeve being applied with one edge overlapping said band and the other end substantially co-terminous with that of said second terminal portion, splitting a portion of said second sleeve near said other end into several strip-like portions and covering said dome and said first and second strips and said first sleeve snugly therewith, with overlap of the strip-like portions with each other, folding back said first terminal portion of said first sleeve and bringing it snugly over all of said band and over a portion of said second sleeve, covering all said strips snugly with an outer rubber member, and partially vulcanizing all said strips, sleeves, band, and said inner and outer members together into an assembly, lightly coating with rubber cement an aluminum head having an axially extending tubular portion for fitting into the interior of said assembly for a distance somewhat shorter than the width of said band, said head having an end flange extending radially outwardly from said tubular portion and provided with a series of axially extending bolt openings, inserting said head into said assembly with said tubular portion engaging the inner cylindrical surface of said assembly and with said flange engaging said open end, inserting into said tubular portion a molded rubber sleeve longer than said tubular portion and pressing it firmly against the inner wall of said tubular portion and against said assembly therebeyond, vulcanizing said head, molded sleeve, and assembly together into a plug, and bolting and gasketing to said flange of said head a metal cap having a central exterior anchor means for securing a cable or chain thereto and fitting means for the application of air under pressure to the interior of said plug.

Claim 11

A method for making a molded inflatable pipe plug, comprising the following steps: molding an inner one-piece rubber member in the shape of a cylinder open at one end and closed by a dome at the other, the dome and cylinder being integral with each other, covering said dome snugly with a first strip of sticky rubber tire cord having unidirectional threads, covering said first strip snugly with a second strip of sticky rubber tire cord also having unidirectional threads running at about 45° with respect to the threads of said first strip, covering said cylinder snugly with a first sleeve of sticky rubber tire cord having unidirectional threads, said first sleeve having a first terminal portion extending well beyond said open end and a second terminal portion extending beyond the juncture of said cylinder and dome, said threads lying at about 10° to an axially extending longitudinal line, splitting said second terminal portion into several strip-like portions and covering said dome and said first and second strips snugly therewith, with overlap of the strip-like portions with each other, applying to said cylinder snugly over said first sleeve adjacent to said open end a circumferential band of sticky rubber tire cord with unidirectional threads running circumferentially, covering a portion of said band and a portion of said first sleeve snugly with a second sleeve made from sticky rubber tire cord with unidirectional threads lying at about 10° to said longitudinal line in the opposite direction from those of said first sleeve, thereby forming an angle of about 20° with them, said second sleeve being applied with one edge overlapping said band and the other end substantially co-terminous with that of said second terminal portion, splitting a portion of said second sleeve near said other end into several strip-like portions and covering said dome and said first and second strips and said first sleeve snugly therewith, with overlap of the strip-like portions with each other, folding back said first terminal portion of said first sleeve and bringing it snugly over all of said band and over a portion of said second sleeve, covering all said strips snugly with an outer rubber member, and partially vulcanizing all said strips, sleeves, band, and said inner and outer members together into an assembly, lightly coating with rubber cement an aluminum head having an axially extending tubular portion for fitting into the interior of said assembly for a distance somewhat shorter than the width of said band, said head having an end flange extending radially outwardly from said tubular portion and provided with a series of axially extending bolt openings, inserting said head into said assembly with said tubular portion engaging the inner cylindrical surface of said assembly and with said flange engaging said open end, inserting into said tubular portion a molded rubber sleeve longer than said tubular portion and pressing it firmly against the inner wall of said tubular portion and against said assembly therebeyond, vulcanizing said head, molded sleeve, and assembly together into a plug, and bolting and gasketing to said flange of said head a metal cap having a central exterior anchor means for securing a cable or chain thereto and fitting means for the application of air under pressure to the interior of said plug.