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:
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.