Influence of the Press Closing Time Upon the Properties of HDF Panels

The closing time of the press is an important technological parameter which influences the density profile of the panels. It also has a decisive influence within the gluing process. When the closing time is too high, the adhesive hardening begins premature due to the heat radiation of the press platens. The resulting panels are fragile and have a very low internal bond. However, the reduction of the press closing time is limited by technical considerations. The present research envisaged an in depth study of this aspect, with a view to establish if it is possible to obtain optimized characteristics of the HDF panels (3mm thick door-skins) by reducing the press closing time from 3s to 2s

Socio-metamorphosis of the academic library

This article is a contribution to the debate on the reform of the library and the new roles it must embrace. Our point of view is that this reform process could be greatly facilitated by creating more means of communication, both epistemic and practical, between sociology and disciplines surrounding librarianship. The main thesis we sustain in the pages of this paper is that the reconfiguration of the library, starting from the user, considered as the first focal point, cannot be accomplished without a very rigorous use of sociological instruments

Socio-metamorfoza bibliotecii academice

Acest articol îşi propune să contribuie la dezbaterea privind reforma bibliotecii şi noile roluri pe care aceasta trebuie să le asume. Punctul de vedere pe care îl argumentăm aici este că acest proces de reformă ar putea fi mult uşurat dacă s-ar crea mai multe căi de comunicare, atât epistemice, cât şi practice, între sociologie şi disciplinele grupate în jurul biblioteconomiei. Principala teză pe care o susţinem în paginile acestei lucrări este că reconfigurarea bibliotecii plecând de la utilizator, considerat drept prim punct focal, nu poate fi dusă la bun sfârşit fără utilizarea foarte riguroasă a unor instrumente sociologice

EVALUATION OF A KILN INCORPORATING AN OSCILLATING PLATE AIRFLOW SYSTEM

Boards of spruce (Picea abies) were dried in a pilot kiln with an oscillating plate that provides -"alternating air movement in the stack". The paper outlines the airflow concept and provides results for drying time and quality.It is suggested that the system has certain advantages which make it suitable as an alternative to conventional drying, especially for small-sized enterprise

Research Concerning the Bending Properties of Reconstituted Spruce Lumber Boards, Obtained by Edge-Cutting at 45° and Gluing

The best-possible valorization of each cut log is a priority. The aim of this research was to evaluate the potential of a solution for increasing the conversion efficiency of tapered logs, by edge-cutting the narrowest sideboards at 45° and joining them by gluing, in order to obtain usable lumber boards. The modality of obtaining the glued elements was described and the values of the density and bending properties (MOE and MOR) of these elements compared to solid wood elements taken from the same logs and the same position within each log was determined. The envisaged outcome was to determine if the bonded products are suited to be used as cores within laminated products for construction

Influence of Heat Treatment Duration on the Machinability of Beech Wood (Fagus sylvatica L.) by Planing

The comparative behavior of heat-treated and untreated beech wood (Fagus sylvatica L.) were studied in response to planing. Beech wood samples were heat-treated in an electric oven without air circulation, at atmospheric pressure, at 200 °C for 1, 2, 3, 4, 5, or 6 h. After conditioning, both the heat-treated samples and the untreated controls were planed at a rotation speed (n) of 4567 rpm and a feed speed (u) of 10 m/min via a “silent power” cylindrical cutter. The cutting power was measured during machining by a Vellemann DAQ board. After processing, the surface quality was measured along and across the cutting direction with a stylus MarSurf XT20 instrument, and the processing roughness was assessed by the roughness parameter Rk. The influence of the heat-treating duration upon the cutting power and the processing roughness were analyzed and correlated to the mass loss after the heat treatment. Linear regression functions were generated for both of the correlations

Milling of Heat-Treated Beech Wood (Fagus sylvatica L.) and Analysis of Surface Quality

Several previous studies have investigated the effects of heat treatment on the chemical composition, along with the physical and mechanical properties, of wood from various species. However, the effects of these property changes upon the machining properties and surface quality of machined wood have been studied much less. The main goal of this work was to investigate the comparative cutting power consumption during milling and the resulting surface roughness of heat-treated and untreated beech wood (Fagus sylvatica L.). Several cutting regimes were tested by combining different values of rotation speed, feed speed, and cutting depth. The cutting power and the processing roughness were assessed and compared. The results clearly showed that the cutting power involved in the milling of heat-treated beech wood was up to 50% lower than that of untreated wood, but the processing roughness was slightly higher