about marine plywood
Transcription
about marine plywood
Marine plywood COMPENSATI TORO S.p.A. via Piverone, 4 - 10010 AZEGLIO (TO) - ITALY tel.: (+39)0125687999 - fax: (+39)0125687979 – e.mail: info@compensatitoro.com - web: www.compensatitoro.com To be classified as "marine” plywood must satisfy both the following requirements: 1. a natural durability of the wood that makes it sufficiently resistant to fungal decay, namely the agents of biodegradation most dangerous and diffuse in the service conditions where the panel is normally used; 2. a bonding quality that can withstand the negative consequences of any changes in moisture and climatic/environmental stresses related to its installation. On request, panels can be overlaid with decorative sliced veneers (also in thicknesses up to 25/10 mm) or can be made with holly inlay (in white painted wood or black rubber stripes). There are also available composite panels (in sandwich structure) made with core of PVC, polystyrene or other materials with higher thermoinsulating properties, which presents good stiffness and very low density. These panels are an adequate solution for realizing floors, walls, partitions, doors and ventilated roofing systems. The first property is determined by specific test protocols and it is expressed by the assignment of a class that can range from 1 (for the most durable timbers) to 5 (for those easily perishables). The standard EN 350-2 gives the classification of natural durability for the solid wood of the main timbers used in Europe. Bonding quality is instead ensured by the adoption of a melamine or phenol-formaldehyde adhesive and is checked through specific laboratory tests (according to the methods specified in EN 314) after a pre-treatment of the specimens of 72 hours in boiling water. Typically, the marine plywood is also characterized by a high number of layers that improves the dimensional stability and makes it more uniform in terms of resistances in the plane of the panel and in its two main grain directions. All of these special features give to the panel the ability to be used for furniture and other components in the marine industry and for several applications in construction. The wood species most commonly used in the production of marine plywood are the Okoumé, the African mahogany (Khaya, Sapele and Sipo) and Teak (this latter is mainly used as decorative sliced veneer, for overlaying panels of the above species). Marine plywood manufactured at Compensati TORO is certified by RINA (the Italian Shipping Register), with document N. DIP060908CS. Its technical properties are also certified by Lloyd’s Register (with document n° 05/00038) according to BS1088-1:2003, which is the best known international reference for this type of product. Moreover this plywood complies with the standard EN 13986 relating to the CE marking of wood-based panels for construction. All marine plywood are made by thermo-setting resins with very low formaldehyde emission, and are then suitable for use in confined environments or service situation that promote its release. The certification of the Quality Management System acquired by the company in accordance to ISO 9001:00 is an additional guarantee of reliability for the plywood supplied. Marine plywood with faces on rotary cut or sliced veneers of Okoumé, Sapele and Teak The Okoumé (Aucumea klaineana) is easy to work, has a rosy color, is a light wood and presents a natural durability of class 4. Khaya (Khaya sp.) and Sapele (Entandrophragma cylindricum) are African timber belonging to the group of mahogany; they show a nice decorative appearance (the Sapele also a specific smell), are reddish in color and have a natural durability relating to class 3. The manufacturing process concerns the entire production cycle, starting from logs suitable for rotary cutting. This allows the factory to realize panels with different size, in order to satisfy special requirements of the customers. It is also available a wide stock of veneers and other semifinished wood-based materials, that are particularly important for reducing the delivery time of standard panels. Marine plywood manufactured by Compensati TORO consists of selected veneers: those used for the external layers are of the classes I-II/II (formerly AB/B) of surface appearance (according to the standard EN 635), while those that compose the inner layers have their longitudinal edges glue joined, so that the final panel do not shows any gaps or discontinuities. The thickness ranges from 4 to 50 mm. In some cases the panels can be either produced in a mixed composition with different wood species or with Okoumé faces and the inner plies of other rotary cut veneers but at least of the same class of durability. When the weight is a critical factor, that combination may be specifically targeted to obtain a panel of lower average density. Marine plywood is one of the wood-based panels most technically interesting, valuable and durable. Its performances make it particularly suitable for all exposures in which severe and moist operating conditions are such as floors, expected, partitions, curtain walls and furniture of pleasure craft. For its specific features and nice appearance this plywood is also a suitable material for windows, doors or other components for construction. A specific example is the use of marine plywood to realize the typical external shutters which are very popular in the area of Venice in Italy.