FOUR LAYERS POLYOLEFIN RESIN COVERING STEEL PIPE

• Main Author: YOSHIZAKI NOBUKI
• Format: Patent
• Language: English; Japanese
• Published: 05.10.2017
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; JOINTS OR FITTINGS FOR PIPES; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; LIGHTING; MEANS FOR THERMAL INSULATION IN GENERAL; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS

PROBLEM TO BE SOLVED: To resolve problems of low-temperature anti-shock characteristic and a long period weather resistance of the conventional three layers polypropylene resin coating steel pipe and a problem of a consistency with a coating at site under application of different kinds of material due to the fact that a usual coating at a welded joint part is of polyethylene resin.SOLUTION: Four layers polyolefin resin high corrosion-proof coated steel pipe has a feature that it is configured by a primer layer 2 formed by coating powder epoxy resin on the surface of a steel pipe 1 as a main body structure that is processed with a surface treatment; a modified polypropylene resin adhesive layer 3; a polypropylene resin layer 4 having irregularity at its surface; and a polyethylene resin layer 5. An end part covering configuration is of a conventional three layers polyethylene resin covering steel pipe having a primer layer 6 coated with powder epoxy resin, a modified polyethylene resin adhesive layer 7 and the polyethylene resin layer 5 newly formed after coating of three layers polypropylene resin covering that are laminated, thereby an end part sealing characteristics and a consistency with covering at site are increased to improve an anticorrosion characteristic.SELECTED DRAWING: Figure 1 【課題】従来の３層ポリプロピレン樹脂被覆鋼管の低温の耐衝撃性と長期の耐候性の問題、溶接継ぎ手部の一般的な被覆がポリエチレン樹脂であるのに対して、異種材料が使用されていることによる現地被覆との整合性の問題を解決する。【解決手段】４層ポリオレフィン樹脂重防食被覆鋼管が、本体構造として下地処理を行った鋼管１の表面に粉体エポキシ樹脂を塗装して形成したプライマー層２、変性ポリプロピレン樹脂接着剤層３、表面に凹凸を有するポリプロピレン樹脂層４、ポリエチレン樹脂層５を形成した事を特徴とする。端部の被覆構成は、３層ポリプロピレン樹脂被覆後に、新たに形成する粉体エポキシ樹脂を塗装したプライマー層６、変性ポリエチレン樹脂接着剤層７、ポリエチレン樹脂層５が積層された従来の３層ポリエチレン樹脂被覆鋼管の構造とすることで、端部のシール性と現地被覆との整合性を高めて防食性を改善する。【選択図】図１