Abstract:
A pipe section with a concrete core having joint-forming ends and devices for restraining bolts by which joints between connected pipes are closed and prevented from opening, the pipe core being encircled by a tensioned helical wire wrapping continuous lengthwise of the core pipe over and across the locations of anchors by which the bolt-restraining devices are mounted to the core pipe.
Abstract:
A system of protecting pipes with bell and spigot joints (having metal parts) from corrosion by fitting between the spigot and bell at least one dry distortable band of open celled material (preferably reticulated polyurethane foam) having a particulate alkaline material (preferably Portland cement) impregnated therein and engaging the band between the bell and the spigot. On wetting of the band, the alkaline material is hydrated to form a water impervious hard sealant which protects the metal after ''''metal'''' insert by protracted release of alkali.
Abstract:
A method for joining nonmetallic pipes underground, with the pipes having mating pairs of bells and spigots, by fitting between mating spigots and bells dry distortable bands of an open celled material (preferably reticulated polyurethane foam) having a particulate water reactive material (preferably portland cement) impregnated therein and engaging each of the bands between one of the bells and its mating spigot. On wetting of the bands with water, the water reactive material therefor forms a water impervious hard sealant.
Abstract:
In a prestressed concrete pressure pipe it is known to have the tensioned wire wrapping around a concrete pipe core terminate short of the bars outside joint-sealing surface at the end of the pipe core, embedded pretensioned wires extending axially of the core, and a tensioned ring either within or outside of the unwrapped or bare end of the core. In the present invention end portions of the pretensioned wires are bent outwardly at a hoop towards the unwrapped surface of the core and the hoop is pretensioned by the wires. The stress in the wires is thereby utilized to impart radially inwardly directed forces emanating from the bent-out portions of the wires and from the hoop to restrain flaring and cracking of the unwrapped end of the core.
Abstract:
A method for joining nonmetallic pipes underground, with the pipes having mating pairs of bells and spigots, by fitting between mating spigots and bells dry bands of an open celled material (preferably reticulated polyurethane foam) having a dry hydratable cement (preferably portland cement) impregnated therein and engaging each of the bands between one of the bells and its mating spigot. On wetting of the bands, the cement hydrates thereby hardening.
Abstract:
A method of protecting pipes with bell and spigot joints (having metal parts) from corrosion by fitting between the spigot and bell at least one dry band of open celled material (preferably reticulated polyurethane foam) having a particulate alkaline material (preferably Portland cement) impregnated therein and engaging the band between the bell and the spigot. On wetting of the band, the alkaline material is hydrated to protect the metal.
Abstract:
A system of protecting pipes with bell and spigot joints (having metal parts) from corrosion be fitting between the spigot and bell at least one dry band of open celled material (preferably reticulated polyurethane foam) having a hydratable cement (preferably Portland cement) impregnated therein and engaging the band between the bell and the spigot. On wetting of the band, the cement is hydrated to form a water impervious hard sealant in the joint which releases alkalinity to protect the metal.