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US 4,366,972 AGranted
Pipe coating system
AssigneeAmeron-Price Company
InventorM. James Franklin
Life of this patent
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AssigneeAmeron-Price Company
InventorM. James Franklin
Estimating the term…
A seamless coating system especially applicable to a welded bell and spigot type joint for steel pipe of exceptionally great length and diameter features a double layer of coating material applied to the outside surface of the pipe and extending over the joint. Use is made of a filler bridge of substantially solid elastomeric material which, though yieldable when covered with the coating material and compressed, yields only to a limited degree. The bridge is made slightly thicker than the thickness of the pipe wall so that when the bridge is applied against a sharp corner at the joint, the bridge material extends above the corner both before and after two successive layers of coating material are applied to the exterior of the pipe wall and the joint. The composition of the bridge is such that it does not compress sufficiently to expose the sharp corner under loads imposed during fabrication of the system and during handling, storage, and shipment of the system, thereby to avoid having the corner create a thin condition in the coating material where it extends over the joint and impair the integrity of the coating.
A seamless coating system for a multiple unit steel pipe assembly having an overlapping type joint between effective overlying and underlying ends of adjacent units wherein there is an annular sealing weld at the joint between the underlying end of one unit and the overlying end of the adjacent unit, an annular end wall on the overlying end, and an exterior annular corner at the exterior edge of said overlying end, said system comprising a first coating strip on said assembly extending throughout the length of both units and over said joint in spiral partially overlapping turns, a second coating strip overlying the first coating strip and extending throughout the length of the both units and over said joint in spiral partially overlapping turns, and an annular filler bridge at the joint between the exterior surface of the assembly and the interior surface of said first coating strip, said filler bridge comprising an elastomeric material in the recess formed by the annular end wall of said overlying end and the exterior surface of said one adjacent unit, said filler bridge having an initial thickness in excess of the thickness of said overlying end at said corner, said filler having a composition such that the outer surface of the filler bridge will not be depressed sufficiently to expose said annular corner under loads imposed during fabrication of said system and during handling, storage, and shipment of the system.
A seamless coating system for a multiple unit steel pipe assembly having an overlapping type joint between effective overlying and underlying ends of adjacent units wherein there is an annular sealing weld between the underlying end of one unit and the overlying end of the other unit, an annular end wall on said overlying end, an exterior annular corner at the exterior edge of said overlying end and an annular recess between said annular corner and said underlying end, said system comprising a first coating layer on said assembly extending throughout the length of both units and over said joint, a second coating layer overlying the first coating layer and extending throughout the length of both units and over said joint, and an annular filler bridge at the joint between the exterior surface of the assembly and the interior surface of said first coating layer, said filler bridge comprising an elastomeric material in said recess, said filler bridge having an initial thickness in excess of the thickness of said overlying end at said corner, said filler having a composition such that the outer surface of the filler bridge will not be depressed sufficiently to expose said annular corner under loads imposed during fabrication of said system and during handling, storage, and shipment of the system.
A seamless coating system for a multiple unit steel pipe assembly having an overlapping type joint between overlying and underlying ends of adjacent units wherein there is an annular sealing weld at the joint between the underlying end of one unit and the overlying end of the other unit, an annular end wall on said overlying end, an exterior annular corner at the exterior edge of said overlying end and an annular recess between said annular corner and said underlying end, said system comprising layers of coating material on said assembly extending throughout the length of both units and over said joint, and an annular filler bridge at the joint and between the exterior surface of the assembly and the interior surface of said layers of coating material, said filler bridge comprising an elastomeric material in said recess, said filler bridge having an initial thickness in excess of the thickness of said overlying end at said corner, said filler having a composition such that the outer surface of the filler bridge will not be depressed sufficiently to expose said annular corner under loads imposed during fabrication of said system and during handling, storage, and shipment of the system.
A method for forming a seamless coating system on a multiple unit steel pipe assembly having an overlapping type joint therebetween comprising effective overlying and underlying ends of adjacent units and wherein there is an annular sealing weld between the overlying end of one unit and the underlying end of the other unit, an annular end wall on said overlying end, an exterior annular corner at the exterior edge of said overlying end and an annular recess between said annular corner and said underlying end, said method comprising applying a filler bridge of elastomeric material in strip form and of thickness in excess of the thickness of said overlying end to the exterior of the other of said units at said recess and abutting one end of said filler bridge against said annular end wall, said filler having a composition such that the outer surface of the filler bridge will not be depressed sufficiently to expose said annular corner under loads imposed during fabrication of said system and during handling, storage, and shipment of the system, continuously moving said assembly in an endwise direction past an extruding station and at the same time continuously rotating said assembly, first projecting an endless strip of adhesive material onto the exterior of a first of said units at said extruding station and simultaneously projecting an endless strip of synthetic plastic resin material onto the exterior surface of the adhesive material at said extruding station, projecting said adhesive material and said synthetic plastic resin material successively over said filler bridge as the filler bridge passes the extruding station, and then continuing projection of said adhesive material and said synthetic plastic resin material onto said other unit until said other unit is coated.
Dependencies are inferred from the claim text.