Your search resulted in 115 documents. Displaying 25 entries per page.
The use of zirconium as an inert fixative for borates in preservation
2001 - IRG/WP 01-30256
Stand-alone borates have been used in internal protected situations as wood preservatives for about 60 years. They have not been deemed acceptable for external situations because of their leaching characteristics. Work carried out to reduce the leachability of borates has been reviewed briefly here, and a specific fixation agent based on zirconium has been tested in standard leaching and decay tes...
J D Lloyd, J L Fogel, A Vizel
A new model for wetting and drying of wood end-grain – with implications for durability and service-life
2011 - IRG/WP 11-20477
New experimental data for wetting and drying of wood end-grain, Sandberg (2009), imply that traditional models for moisture transport are not at all applicable. A new model is developed to consider the phenomenological behaviour of water transport in and out of end-grain, using the pore water pressure and sorption scanning properties. Modelling results are compared to experimental results and the ...
L-O Nilsson, K Sandberg
Methods of treatment of wood preservatives. The selection of appropriate preservation process with particular reference to mixed tropical forest resources. A key address
1982 - IRG/WP 3177
All wood is biodegradable. Many timber species have, however, sufficient natural durability to permit their use, particularly in protected situations, without any special precautions. Many others, of course, are readily attacked by insects and where there is sufficient moisture and air, by wood-decaying fungi. It is these timber species which benefit most from treatment with wood preservatives. Ev...
C R Levy
Washboard effect: A surface deformation of spruce resulting from vacuum-pressure impregnation with water-borne preservatives
1987 - IRG/WP 3450
The washboard effect has been observed in sawn spruce after both commercial and laboratory based preservative treatments and is of increasing economic importance. The effect is defined as a specific phenomenon at the wood surface. It is distinct from internal collapse in the wood, but it may occur in association with internal collapse damage. Experimental investigations on the causes of washboardi...
H Willeitner, R J Murphy
Treating Eucalyptus tereticornis wood with boron: Optimizing treatment conditions
2005 - IRG/WP 05-40309
Even though Eucalyptus tereticornis wood is suitable for small timber purposes, being non-durable, it needs to be treated with preservative chemicals. As it is a heavy, hard and difficult to treat species, the possibility of using diffusible boron compounds was investigated. The present study explored the effect of impregnation conditions such as treatment schedule, concentration of treatment solu...
T K Dhamodaran, R Gnanaharan
Resin bleed after light organic solvent preservative treatment - the effect of drying method and process type
1986 - IRG/WP 3378
The effects of drying method and treatment process type on resin bleed were investigated. High-temperature drying of resinous radiata pine (Pinus radiata D. Don) heartwood resulted in improved wood permeability, higher preservative uptake, and greater resin bleed when treated by the Rueping process. Resin bleed was reduced substantially when timber was treated by the Lowry process, and totally eli...
P Vinden
Observations on the uptake and penetration of various liquids in clear heartwood and sapwood of Pinus radiata D.Don
1983 - IRG/WP 3224
Volumetric uptake of water (aqueous copper-chrome-arsenic (CCA)) or methanol, applied by bulk hydrostatic pressure to air dried clear heartwood specimens of Pinus radiata D. Don, far exceeds that of a wide variety of polar and non-polar solvents. In air dried sapwood, the volumetric uptake of CCA tends to be less than that achieved for most solvents including methanol. No comprehensive explanation...
J E Barnacle
Artificial drying of impregnated wood
1987 - IRG/WP 3448
Sawn timber (Pinus Sylvestris) of dimension 50x150 mm was impregnated with CCA by a full-cell process. The timber was then dried in a conventional kiln or a special vacuum kiln where the timber was dried by circulating superheated steam. Drying time was 16 days and 2 days respectively. The aim of the investigation was to compare the physical appearence of the wood after drying by the two methods w...
M-L Edlund
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
Kiln drying of CCA-treated wood - Some safety and environmental considerations
1987 - IRG/WP 3443
Vapours and condensate from a condenser kiln in which CCA-treated wood was being dried have been collected and analysed. The concentrations of arsenic, copper and chromium found in the vapours from the drying process were well below Swedish threshold limit values. The contents of arsenic and chromium were also low in the condensate, although the copper content was fairly high. The latter result wa...
J Jermer, B Lundberg
Dip-diffusion of dressed timber - Effect of drying
1989 - IRG/WP 3509
The effect of drying on dip-diffused dressed freshly sawn timber was determined by the depth of penetration of boron achieved on the two test timber species, White cheesewood (Alstonia scholaris) and Light Hopea (Hopea papuana). The results obtained showed that light density White cheesewood was completely penetrated even after 3 days drying while Light hopea, treated immediately achieved 5.2 mm p...
H C Konabe
The treatment of sawn whitewood with organic solvent wood preservative
1982 - IRG/WP 3192
The impregnation schedules approved in the UK for the treatment of sawn European whitewood (Picea abies) with organic solvent borne preservatives result in comparitively high loadings relative to the limited depth of penetration they achieve. Results are presented, which show how substantial reduction in the overall loading may be achieved without concomitant reduction in penetration. A model for ...
L D A Saunders
Presteaming radiata pine heartwood to improve treatability
1983 - IRG/WP 3239
Steaming and holding before preservative treatment by the Bethell process greatly improved the treatment of radiata pine heartwood. Maximum penetration of preservative for the shortest holding period was obtained by the use of steam vacuum but the difference between this and steam venting was small when compared with the standard of treatment of air dried samples. A holding period of one day was s...
A J Bergervoet
In vitro sporulation of selected wood decay fungi
1978 - IRG/WP 190
Basidiospores produced axenically without laborious attention in the laboratory are useful in studies of wood decay initiation. Such spores presumably approach those collected from natural sporophores in size and germinability (Morton, 1964). Production of spores in vitro by inversion of cultures grown on 2% malt extract agar in deep glass dishes (100x80 mm²) has been the preferred method (Morton...
E L Schmidt, D W French
Internal pressure monitoring during the treatment of Pinus radiata (D. Don)
1995 - IRG/WP 95-40049
The use of micro-transducers to monitor the internal pressure of wood during treatment is investigated. The rates of pressure transfer in radiata pine sapwood and heartwood are compared during Bethell treatment with copper chrome and arsenic preservative. The effect of pre-conditioning treatments are also evaluated using micro-transducer monitoring. It is anticipated that knowledge of the changes ...
P R S Cobham, P Vinden
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 1: Treatment of reference samples
1977 - IRG/WP 426
It was agreed in Wildhaus on 15 May 1976 that preparations for the test detailed in Document No: IRG/WP/414 should commence immediately, but that initially only two water-borne preservatives should be used - a copper/chrome/arsenic (CCA) and a copper/chrome/boron (CCB) formulation respectively. PRL, England (R Cockcroft) would be responsible for supplying samples of the reference timbers treated w...
R Cockcroft, T B Dearling, W O Schulz, H V Borck
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
An investigation of the effects of pre-steaming on the treatment of sawn spruce timber with Celcure A, a copper/chrome/arsenic preservative
1981 - IRG/WP 3180
Difficulties in the treatment of spruce using standard vacuum/pressure techniques with both water-borne and organic solvent preservatives are well known. The growth characteristics of spruces (Picea spp) make them attractive candidates for forestry schemes. In 1975 the UK Forestry Commission had about 400 000 hectares, about 20% of total UK forest area, planted with Sitka spruce (Picea sitchensis)...
C R Coggins
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
Behaviour of some selective Indian species towards treatment with solvent based water repellent preservative
1984 - IRG/WP 3309
This paper discusses a solvent based preservative using PCP and a water repellent for preserving three species of timber commonly used in India for the manufacture of doors and windows. It examines the method of treatment to achieve desired levels of penetration and retention of the preservative-cum-water repellent, and tests made on these timbers to examine the success of the processing methods a...
V R Sonti, B Chatterjee
Quality of timber impregnated with preservatives of class AB
after three years in service
2002 - IRG/WP 02-20241
Quality of impregnated timber is most often expressed by penetration and retention of the preservative used. Relatively less information is available about the performance of the final product, e.g. decks, panels etc. regarding product’s surface checks, deformations and overall appearance. Together with the timber durability, the above mention features are of esthetical importance in the above g...
N Terziev
Effects of drying processes on termite feeding behaviour against Japanese larch wood
2001 - IRG/WP 01-10390
We investigated the effects of current drying schedules for larch lumbers on the termite feedings. Thermal analyses were also conducted to investigate degradation of wood components. Choice feeding tests showed specimens dried under high-temperature schedules were evidently susceptible against termite attacks. These schedules produced the feeding-attractants, which were suggested by the TGA result...
S Doi, Y Kurimoto, H Takiuchi, M Aoyama
Volatile organic compounds (VOC) measured during drying of impregnated timber
2004 - IRG/WP 04-50216
Discussion about drying of impregnated timber has taken place in the Nordic countries under eighties and nineties and goes on nowadays. The drying increase the value of production and the customer gets fewer problems when handles the timber. This introduces a positive attitude to the impregnation as a process and its products. Beside the important information about the advantages of impregnated ti...
N Terziev, V Djokic
A field test with anti-sapstain chemicals on sawn pine timber stored and seasoned under different conditions
1984 - IRG/WP 3245
Newly sawn timber of European redwood (Pinus sylvestris L.) was dip treated in four different anti-sapstain chemicals. The protectife effect against sapstain, mould and decay was examined after 10 weeks' and 10 months' storage in open and closed stacks. The results showed that the performance of individual chemicals was different in open and close stacks, although the wood as wel...
D J Dickinson, B Henningsson
Dip-diffusion of dressed timber - Effect of drying
1990 - IRG/WP 3603
The effect of drying on BFCA dip-diffused, dressed, freshly sawn timber was determined by the depth of penetration of boron achieved on two test timber species, White Cheesewood (Alstonia scholaris) and Light Hopea (Hopea papuana). The results obtained showed that the light density White cheesewood was completely penetrated even after 3 days drying while Light Hopea, treated immediately achieved 5...
H C Konabe