Steel Sandwich Panels in Marine Applications

Brodogradnja, 2005

Sažetak Steel sandwich panels welded by laser can offer 30-50% weight savings compared to the conventional steel structures. Helsinki University of Technology/Ship Laboratory has done active research during the past 10 years on various topics related to the laser welded steel sandwich panels. The work carried out includes development of design formulations for the ultimate and impact strength, analysis of fatigue strength for the joints, and development of solutions to improve the behaviour under fire. A number of research ...

1997

New structural components, such as sandwich panels, can be efficiently manufactured by using the deep penetration effect typical to high power beam welding techniques. Sandwich structures offer high accuracy, higher structural performance, increased fire safety as well as benefits in assembly. For the first time those structures arc now available on the market. Potential applications cover both shipbuilding and various areas of structural steel engineering such as bridges, railway vehicles and buildings. To provide a base for successful! application, a considerable amount of structural testing along with the development of efficient manufacturing and assembly methods and the approval of the structure by classification societies has been necessary. This paper briefly describes the manufacturing process and operational properties of sandwich panels.

Lightweight Construction - Latest Developments

New structural components, such as sandwich panels, can be efficiently manufactured by using the deep penetration effect typical to high power beam welding techniques. Sandwich structures offer high accuracy, higher structural performance, increased fire safety as well as benefits in assembly. For the first time those structures arc now available on the market. Potential applications cover both shipbuilding and various areas of structural steel engineering such as bridges, railway vehicles and buildings. To provide a base for successful! application, a considerable amount of structural testing along with the development of efficient manufacturing and assembly methods and the approval of the structure by classification societies has been necessary. This paper briefly describes the manufacturing process and operational properties of sandwich panels.

Polish Maritime Research, 2009

The paper presents a view on selected problems concerning application of steel sandwich panels to marine structures. Such problems connected with specificity of thin-skin laserwelded structure are varying in topics beginning from micro-scale properties of laser-welded T-joint through the joining of sandwich structures together up to connection and integration of such structures with a classical single-skin structure.

9th International Symposium on Practical Design …, 2004

Marine Structures, 2009

This paper investigates the possibilities for structural optimisation of laser-welded sandwich panels with an adhesively bonded core and uni-directional vertical webs. Closed form expressions for the equivalent stiffness and elastic buckling strength of laser-welded sandwich panels are discussed and numerically evaluated to demonstrate the effect of parameter variations on stress and deflection. Due to the number of design variables and constraints a structural optimisation method based on the method of moving asymptotes (MMA) is implemented and used to minimise the structural weight per square meter of panel for a typical accommodation deck configuration. It is concluded that, within the span of production parameters and rule requirements, substantial improvements can be made with or without an adhesively bonded core. Without core material and without any changes to the surrounding structure the structural weight for standard production panels can be reduced considerably, by reducing the face plate thickness and by using thinner and fewer webs. Additional weight can be saved by removing all but a few webs and injecting lowcost polyurethane foam into the cavities, giving added thermalacoustic insulation, or by incorporating a more structural core with greater thickness and higher density, by which the free span of the sandwich panel can be increased.

Lasers in Material Processing, 1997

The demand for bigger, faster and lighter moving vehicles, such as ships, trains, and buses has increased the importance of Efficient structural arrangements. In principle two approaches exist to develop efficient structures: either application of new materials or the use of new structural design. A proven and well-established solution is the use of composite materials and sandwich panels. In this way more strength to weight ratio and minimum weight can be obtained. The sandwich structures have potential to offer a many range of attractive design solutions. In addition to the obtained wt. reduction, these solutions can often bring space savings, fire resistance, noise control and improved heating and cooling performance. Laser-welded metallic sandwich panels offer a number of outstanding properties allowing the Designer to develop light and efficient structural configurations for a variety of applications. These panels have been under active Investigations during the last lots of years in the world. Out okumpu has been participating in several collaborative projects in this area. In Finland the research related to all steel sandwich structure was initiated in 1988 in the Ship Laboratory of Helsinki University of Technology.

Journal of Laser Applications, 2004

Spatial analysis of the back reflected laser light during CO2-laser cutting of metal sheets J. Laser Appl. 25, 012001 (2013); 10.2351/1.4765818

2011