|국가/구분||United States(US) Patent 등록|
|미국특허분류(USC)||405/169; 405/158; 405/170; 405/184.5; 138/115; 138/149|
|발명자 / 주소|
|출원인 / 주소|
|인용정보||피인용 횟수 : 11 인용 특허 : 59|
Methods are provided for installing an electrically heated pipe-in-pipe pipeline on the seafloor. Inner and outer pipe segments are formed and the inner pipe is coated and insulated. Coating may include sprayed polyurethane foam and insulating half-shells that are placed around welds. Epoxy is preferably coated on the inner pipe before other coatings. The segments are loaded on a lay barge and water stops are preferably installed in the annulus as the pipeline is formed. Water stops may be formed by placing a liquid polymer in the annulus and allowing it...
1. A method for installing a segment of an electrically heated pipe-in-pipe subsea pipeline, comprising: (a) providing a plurality of inner pipe joints and outer pipe joints, the inner pipe joints having an outer surface; (b) spraying an insulating ring over the outer surface of the inner pipe joints; (c) inserting the inner pipe joints and the insulating ring into the outer pipe joints to form a first pipe-in-pipe segment, the first pipe-in-pipe segment having an annulus; (d) placing the first pipe-in-pipe segment on a pipe-laying barge; (...