Double-wall tank and method of its manufacture

US5269436A · kind A · utility

Assignee

• Adisa Entwicklungs AG · CH

Inventor

• Werner Bachmann · Hersbruck, DE

Key dates

• Filing date: Aug 11, 1992
• Grant date: Dec 14, 1993
• Expiry date: Aug 11, 2012

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29L2031/7126
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

To improve the strength, resistance to leaks, and formation of tears and fissures in the inner wall of a double-wall tank, the inner wall is formed, as described in the inventor's earlier U.S. Pat. No. 4,739,895 (U.S. Pat. No. Re. 33,421) by a plurality of foil or sheet elements which are overlapped at the edges, and covered by a plastic, preferably epoxy layer. The sheet elements are preferably aluminum foils of from 0.15 to 0.3 mm, preferably 0.2 mm thickness. The plastic layer is reinforced by a multi-ply, preferably two-ply, glass fiber fabric, which is so woven that the layers or plies of the fabric are interwoven or interlocked. The fabric is embedded in the plastic coating, before it is cured, for example by rolling it into the plastic coating. To assure good fitting of the inner wall against the outer wall, a vacuum is applied in the space formed by the projections or puckers of the sheet elements and the outer wall before the plastic coating has cured, and maintained until it is cured. The sheet or foil elements and the reinforced plastic will then form a laminate of high inherent stability with high bending and tensile strength, so that fissures are effectively avoided an…