Low temperature method for forming field joints on undersea pipelines
US8857700B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 2010 |
| Grant date | Oct 14, 2014 |
| Priority date | — |
| Expiry date | Dec 4, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49888
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for forming a field joints between sections of coated or insulated pipe which are to be welded together and incorporated into an undersea pipeline for carrying single or multi-phase fluids such as oil, gas and water. The method includes the application of a liquid epoxy layer which overlaps a lip of the factory-applied FBE coating protruding beyond a chamfered end of the factory-applied insulation layer, and which may be applied over the entire weld joint area. The liquid epoxy layer is partially cured by application of heat, and a layer of powdered adhesive is applied onto the partially cured liquid epoxy layer. The adhesive is subsequently sintered and activated by application of heat to its outer surface. The outer surfaces of the adhesive layer and the chamfers are then preheated and the thermal joint insulation is injection molded over the entire joint area. Throughout the entire method the temperature of the factory-applied FBE coating is maintained below its glass transition temperature so as to avoid weakening the bond between the FBE coating and the underlying steel pipe. The number and sequence of steps can be varied, depending at least partly on whether the liqu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.