Your search resulted in 286 documents. Displaying 25 entries per page.
A behaviour of CCA penetration of fir (Abies bornmulleriana Mattf.) at different ramp times and constant vacuum/pressure applications
2006 - IRG/WP 06-40346
A behaviour of CCA penetration of Bornmulleriana fir (Abies bornmulleriana Mattf.) at different ramp times and constant vacuum/pressure applications was illustrated for the main flow directions by the experimental pictures....
I Usta, R Despot, M Hasan
Health hazards and environmental aspects when using Cu-HDO-containing wood preservatives in vacuum pressure plants
1993 - IRG/WP 93-50001-11
Apart from the biological efficacy of wood preservatives, the health and environmental aspects concerning the utilisation of wood preservatives, the use of treated timber and the disposal of impregnated wood are of high significance today. Therefore, information on a possible aerial concentration of wood preservatives, on the mobility of active substances in soil leached from treated timber in ser...
W Hettler, S Breyne, M Maier
Dynamics of pressure changes in wood during impregnation
1990 - IRG/WP 3615
Conventional methods of impregnation have to be improved for achieving better penetration of refractory wood species. Basic requirements for an adjustment of treatment schedules are, amoung others, a profound knowledge of the course of pressure changes in the wood during treatment. A new method of pressure measurement was developed which supplies exact and reproducible data. The results show that ...
R D Peek, S Goetsch
Impregnation of roundwoods by sap-displacement in Madagasca
1975 - IRG/WP 352 E
The use of roundwoods is already very important in Madagascar and steadily increasing for the following applications: - posts, electricity and telephone line supports (medium voltage) - stakes, piles for civil engineering structures, bridges, gantries, road and port works, etc. - construction of houses (posts, frameworks, piles, etc.) and rural buildings (sheds, stables, piggeries) - fence posts, ...
M Fougerousse, P Guéneau
Recent developments in the treatment of sawn spruce by double vacuum impregnation
1978 - IRG/WP 3114
The timbers used for building purposes in the U.K. and on the Continent of Europe are mainly softwoods. The two types of wood most used are redwood (Pinus sylvestris) and whitewood (Picea abies or Picea sitchensis). Other species are used to a lesser extent when considerations such as a long length requirement or width requirement demand the use of, for example, hemlock, Douglas fir or Parana pine...
C T Kyte, L D A Saunders
An inclination incising technique for the preservative treatment of refractory timbers
1991 - IRG/WP 3664
An inclination incising technique for preservative treatment of refractory timbers was examined by changing cutting angle to the longitudinal direction of test specimen and by using different types of knife edge. Incised wood were impregnated locally into incisions with CCA solution by the specified local pressure process. Width and length of penetration areas of CCA solution were measured on long...
Y Nakamura, K Nishimoto
CCA treatability of 100 timbers of Bangladesh
1996 - IRG/WP 96-40069
CCA treatabilities of 100 timber species grown in Bangladesh have been compared with the treatability of Pole pine (Pinus caribaea) grown in Bangladesh which revealed new five treatability grades. Sapwood of 48% species and heartwood of 9% species was found to be treatable with CCA under grade (++++) having 100% penetration. Like softwood where CCA penetrates completely in cell lumens and cell wal...
A K Lahiry
A study on the pressure impregnation of Eucalyptus globulus fence posts with CCA preservatives. Part 1
1988 - IRG/WP 3470
This paper describes the impregnation with CCA preservatives by full-cell process of Eucalyptus globulus fence-posts. Several treatments were made for different times of initial vacuum and treating pressure, with fence-posts from two coppice plantations (1st and 2nd rotations), assembled into three diameter classes: small, medium, large. The results concerning the absorption and lateral penetratio...
D De Sousa Castro Reimão, L Nunes
Laboratory tests on artificial weathering of Quercus rubra crossties
1986 - IRG/WP 2252
Clear red oak (Quercus rubra) blocks were used to evaluate various types of accelerated aging tests including boil, steaming, and cyclic weathering. It was found that the repeated vacuum and pressure treatment of wood in water, steaming, oven-dry, and freezing appeared to be most effective in reducing the MOE in compression and hardness modules of wood specimens. Red oak crossties which were press...
P Chow, A J Reinschmidt, E J Barenberg, S L Lewis
Chemical evaluation of borate treated pine sapwood attacked by the subterranean termite Coptotermes acinaciformis
1993 - IRG/WP 93-20003
Sapwood of hoop (Araucaria cunninghamii Ait. ex D. Don) and slash (Pinus elliottii Englem.) pines were treated by Vacuum Pressure Impregnation (VPI) to provide test specimens. The concentration of boron was defined by chemical analyses of the timber, in the zone of primary attack by the termite being bioassayed. A common method of definition of preservative retention, weight uptake of preservative...
A R Moffat, B C Peters
Possibilities of improving the oscillating pressure method
1991 - IRG/WP 3668
Studies on the dynamics of pressure changes in wood during impregnation revealed no significant effect of fast pressure changes for green spruce as used by OPM (IRG/WP/3615). The following experiments were carried out on several hundreds of spruce palisades to examine the modification of single procedure parameters of common use OPM and to record the effects on the impregnation result with the aim...
S Goetsch, R-D Peek
A novel solvent penetration assessment technique for wood preservativation treatments using waterborne systems
1990 - IRG/WP 2346
Solvent and hence solute (a.i.) penetration during any wood preservation treatment cycle and the flow pathways taken by the solvent in the wood are crucial elements in determining the adequacy of any treatment. Inadequate solvent penetration into specimens or an inappropriate tissue throughflow pattern during impregnation will markedly affect the distribution pattern achieved by many non-diffusibl...
A J Pendlebury, J Coetzee, E Sorfa, A Botha
The effect of pretreatments on the impregnation of air-dried sawn Belgian spruce
1988 - IRG/WP 3490
In general the impregnation of airdried spruce results in a variable treatment and limited penetration. This is the result of pit aspiration that occurs during drying of the spruce sapwood and heartwood. Spruce timber is becoming of greater importance in Belgium and hence research for better treatment of this vulnerable wood species is needed. Squared airdried timber of different dimensions were e...
J Van Acker, M Stevens
Sawn timber of fir (Abies alba Mill.) - Treatability and usability for the Hazard Classes 3 and 4
1999 - IRG/WP 99-40147
Within a national research project, tests on the treatability on sawn timber of fir (Abies alba Mill.) in oscillation pressure, vacuum pressure and double-vacuum processes have been worked out with 95 trunks taken from 3 different altitude levels (up to a height of 590 metres, 600 to 990 metres and over 1000 metres) and from 4 different regions of Switzerland. As the treatability of round wood can...
E Graf, T Bör
Utilization of coconut timber from north Sulawesi, Indonesia. Part 2: Treatability
1994 - IRG/WP 94-40025
Under tropical conditions coconut wood is quickly degraded by mold and blue stain fungi. Low density wood in ground contact is commonly decomposed by wood destroying fungi within a period of only a few months, higher density wood from the outer stem regions within 24 to 30 months (MOSTEIRO, CASIN, SERIBAN 1976; McQUIRE 1975). Moreover, according to McQUIRE (1975) green wood of lower density is hig...
R-D Peek
Protection of rubberwood timber. Part 1: Impregnation with boron preservatives
1989 - IRG/WP 3551
Rubberwood (Hevea brasiliensis) were treated with a 3% proprietary mixture of borax/boric acid using three different treatment schedules i.e. full-cell, full-cell to refusal and full-cell with 12 cycles of vacuum/pressure. Freshly cut samples had mean preservative retentions of 187 kg/m³, 214 kg/m³ and 178 kg/m³ respectively. Pre-air dried samples for one week had retentions of 252 kg/m³, 308 ...
L T Hong, C C K Liew
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
A new type of biocide suitable for use in different fields of wood preservation
1993 - IRG/WP 93-30014
A new type of polymeric biocides was developed containing quaternary ammonium and boron ester groups as active structure elements, to overcome the disadvantages of AAC's in wood preservation use and to utilise their good performance due to a broad efficacy against fungi on the other hand. The new biocides called polymeric betains have been tested in laboratory and field tests and especial...
V Barth, H Härtner
Tilting and vacuum treatment - two methods to obtain a non-dripping freshly treated timber
1989 - IRG/WP 3535
Modern impregnation plants are designed to prevent spread of impregnation solutions from the plant through leakage, etc. It is also important that freshly treated timber does not spread solutions through dripping on the storage area. To prevent this, the impregnation procedure is terminated with a vacuum period. In many plants in Sweden this period is minimized or even excluded to gain time. Inste...
I Johansson, M-L Edlund
Microdistribution of water-borne preservatives in blue gum treated by full-cell process
1990 - IRG/WP 3617
The present work deals with the study of the microdistribution of copper, chrome and arsenic elements in Eucalyptus globulus Labill. sapwood, treated with a CCA water-borne preservative by full-cell process, with the help of scanning electron microscopy together with energy dispersion X-ray analysis technique. The work shows that the retention of CCA elements is high in vessels and vasicentric par...
D De Sousa Castro Reimão, J M Palacios
Three-year field trials of polymeric formulations which provide a new basis for the invention and design of non-toxic wide-spectrum wood preservatives
1994 - IRG/WP 94-40029
Three types of non-toxic polymeric formulations invented using a new approach to wood preservation were challenged with termites and fungi in three-year ground-contact field trials in the sub-tropical climate of Natal. These formulations were copper soaps of carboxylic acid groups of unsaturated fatty acids of waxes and edible vegetable oils; of resin acids of rosin, and, of synthetic unsaturated ...
A A W Baecker, A Pizzi
Preservation of coppice wood for the fabrication of glued beams or panels
1987 - IRG/WP 3427
In this survey we will examine the specific problems concerning the conservation and the preservation of timber (issued from trunks of small diameter corresponding to products of clearings or coppices) destined for the fabrication of solid reconstituted elements. Thus for six metropolitan species of wood, we first characterized the biological deteriorations which occur after felling and their kine...
G R Y Déon, R Schwartz
Internal pressure development within Oriented Strand Board during supercritical fluid impregnation
2000 - IRG/WP 00-40175
Supercritical fluids (SCF) offer an attractive alternative to conventional treatment processes for delivering material into wood, but there are many unanswered questions concerning the technology. One major concern is the potential for the development of excessive pressure gradients in the wood that might exceed the material properties and lead to crushing or other pressure-induced damage. Previou...
G Oberdorfer, P E Humphrey, R J Leichti, J J Morrell
Fixation of chromated wood preservatives through technical drying
1990 - IRG/WP 3623
Twin samples of sawn timber of Pinus sylvestris and Picea sp. were treated with copper-chromate-containing wood preservatives and subsequently kiln resp. air dried. After drying, the distribution of preservative and rate of fixation were determined. Drying of freshly treated wood in a condenser type kiln at temperatures of 60°C and 80°C and in a vacuum type kiln at 55°C with a pressure of about...
R-D Peek, H Klipp
The potential of high pressure pulsation processes to treat white spruce lumber with water-borne preservatives
1988 - IRG/WP 3471
Laboratory work using end sealed 4x8x46 cm³ white spruce samples has been done to explore the suitability of three variants of a 2.1 MPa pulsation process for the impregnation of white spruce with CCA. The results showed that the process improved significantly the penetration of the preservatives and reduced significantly cell collapse, when compared with the results of treatment using a 2.1 MPa ...
J P Hösli, J N R Ruddick