RESEARCH CONCERNING THE RELIABILITY OF MOULDED ELASTIC ELEMENTS MADE OF LAMINATED VENEERS

Virgil Sorin ISTRATE
Eng. - S.C. ITALTRUCK Sibiu, Romania
Tel: 0040 722 360654

Ionel TOMESCU
Eng. - GENERAL ELECTRIC WATER AND PROCESS TECHNOLOGIES ONTARIO
Address: 3 PICKARD AVENUE, Ancaster, L9K IT2, Ontario, Canada
Tel: 001 905 304 8631

Virgiliu ISTRATE
Prof.Dr.Eng. - Universitatea "Transilvania" Brasov - Facultatea de Industria Lemnului
Address: B-dul Eroilor nr. 29, 500036 Brasov, Romania
Tel: 0040 268 412921/192. Fax: 0040 268 415315

Abstract: Elastic elements are moulded, laminated products obtained by gluing several layers of structural veneers in a hot press. These elastic elements, with curved or plane shape, are used to achieve elastic structures for lounging furniture (beds, couches etc.). Elasticity is the basic characteristic of these elements and its maintaining in time (reliability) is an essential requirement.
The paper presents an original method for testing the reliability of curved elements, by means of an original device, especially conceived and produced by the authors for this purpose. Placed in this device, the elastic element is subiected to repeated bending tests, which simulate the real loads which act upon these elements in service, respectively when the man uses the piece of furniture for specific activities (sleep, rest, medical recovery etc.).
After a certain number of loads (1000-5000) each elastic element is analyzed by evaluating: the deflection, the bending force before and after testing, the slide in the bearing, the shape of the elastic element, the delamination of the veneers within the loading area, the appearance of cracks on the veneer edges, the bending strength.

Key words: reliability, deflection, elasticity.

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