Your search resulted in 405 documents. Displaying 25 entries per page.
Effect of double-vacuum and vacuum-pressure impregnation with water-borne preservatives on the dimensional characteristics of spruce
1990 - IRG/WP 3613
Air-dried planed spruce (Picea abies) samples were treated with a water-borne preservative (micro-emulsion) and one oil-borne type both containing azaconazole and deltamethrin. Each set of samples contained equal number of specimens with different growth ring orientation, heartwood content and density. In addition to the preservative retention and the penetration of a.i., the swelling of the sampl...
J Van Acker, M Stevens, G Rustenburg
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
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. 3rd Interim Report
1983 - IRG/WP 4101
This paper updates the results of microbiological examination and marine borer assessment of untreated wood samples (15 x 2 x 2 cm³) and samples treated with 3, 6 and 10% CCA and CCB preservatives. Three reference species - Alstonia scholaris, Fagus sylvatica, Pinus sylvestris were used at all the test sites in addition to local species chosen by participants in the test....
R A Eaton
Natural durability of some common Indian timbers and marine plywood against biodeterioration in Kochi waters (India)
1992 - IRG/WP 92-4177
Panels of thirty-eight timber species and marine plywood were tested in Kochi harbour (South-west India) for periods ranging from 3 to 21 months, so as to evaluate their natural resistance against marine borers. Results indicate that all the timber species studied are non-durable, 6 of them having undergone more than 50% internal destruction within 3 months; 14 species in 6 months, 13 species and ...
L N Santhakumaran, M V Rao
Water-borne preservative marine trials in Western Canada
1981 - IRG/WP 470
Red pine boards treated with chromated copper arsenate, ammoniacal copper arsenate, copper zinc arsenic additive, a modified ammoniacal copper arsenate, and zinc arsenic additive, have been installed in a marine field test at West Vancouver, British Columbia. After two and a quarter years exposure, all the test samples are in excellent condition with the exception of those treated with the zinc ar...
J N R Ruddick
Ancillary properties of vapor boron-treated composites
2001 - IRG/WP 01-40210
This paper discusses the water absorption, thickness swelling, and internal bond strength of North American composites treated using a vapor boron treatment process. For oriented strandboard, high boron loadings led to lower internal bond strength and lower thickness swelling. Water absorption results were variable but no deleterious effect of treatment was noted. For medium density fiberboard, th...
W A Jones, H M Barnes, R J Murphy
Heat treatment of wood strands for OSB production: Effect on the mechanical properties, water absorption and dimensional stability
2002 - IRG/WP 02-40238
The effect of heat treatment on the mechanical and physical properties of commercial OSB strands was evaluated. Heat treatment was applied under inert atmospheric conditions to wood strands. The aim of this study was to examine the heat treatment parameters to achieve significant reduction of thickness swelling (upon exposure to moisture in service) without causing excessive
reductions in stren...
G J Goroyias, M D C Hale
Water sprinkled pine wood: A microscope study on boards showing streaking
1993 - IRG/WP 93-10033
Boards sawn from the outer sapwood of pine lumber previously water sprinkled for periods of 10-18 weeks and kiln dried, showed streaking after staining. Two types of enhanced stain uptake were noted: 1) a more concentrated and localized form after 10 weeks and 2) a more diffuse type which developed in later stages of water sprinkling. Areas showing enhanced stain uptake were examined using light a...
G F Daniel, T Elowson, T Nilsson, A P Singh, K Liukko
Water-borne wood preservatives against marine borers. Results from NWPC marine trials started in 1972 and 1976
1990 - IRG/WP 4162
The paper presents the results from NWPC (Nordic Wood Preservation Council) marine trials started in 1972 and 1976. The trials are carried out according to the NWPC Standard No. 1.4.2.2./73 "Marine test - a test against marine wood boring organisms in sea water". The test site is Kristineberg Marine Biology Station on the west coast of Sweden. The wood blocks used in the trials were made from sapw...
Ö Bergman, C Lundberg
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 9: Report of third inspection (2 years) in Italy
1980 - IRG/WP 461
The wood samples were submerged in the sea at Follonica, Italy, in April 1977. Follonica, latitudine 42°55' North and longitude 10°45' East, is situated on the Tyrrhenian sea. The recorded temperature varies between 13°C to 25°C, salinity 37-38% and pH about 8. The inspections were carried out after 6 months (10/1977), 1 year (4/1978) and 2 years (4/1979)....
A Gambetta, E Orlandi
How to keep coated wood structures sufficiently dry to avoid damage caused by rot
1991 - IRG/WP 2376
During the last ten years, a new type of problems with wood rot has emerged in Scandinavia. Thousands of houses have been damaged by wood rot attaching to the exterior wood panel. This paper provides an overview of finished and ongoing work in order to identify the cause of these problems. In field tests, the moisture conditions were measured in panels coated with different paint systems. The infl...
S Hjort
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 7: Second report on the samples in Papua New Guinea
1980 - IRG/WP 459
This report presents the findings to date regarding specimens installed in Papua New Guinea, as part of a world-wide marine trial of certain timbers treated with CCA or CCB preservatives. The details of the trial are set out in document number IRG/WP/414. The report discusses the findings in the context of the conditions prevailing at the trial site and of the properties of the trial timbers. The ...
S M Cragg, C R Levy
Leachability of borate-modified oriented strandboard: A comparison of zinc and calcium borate
2002 - IRG/WP 02-40232
The leachability of boron in zinc and calcium borate-modified oriented strandboard (OSB) was investigated in this study. The leaching experiments were conducted by exposing edge-sealed OSB samples under running water for 8, 24, 72, and 216 hours. The results were compared with those from the unleached controls. Boron leaching of the modified OSB occurred upon the initial water exposure, and the le...
S Lee, Q Wu
Highly virulent wood-rotting Basidiomycetes in cooling tower timbers
1995 - IRG/WP 95-10125
Over the past ten years most industrial cooling towers changed their water treatment systems in order to meet environmental requirements. Since this alterations wood rot attack has been reported more frequently. Several Basidiomycete fungi were isolated and determined. Amongst the most important ones are strains of Physisporinus vitreus (Pers.:Fr.) P. Karst., Phellinus contiguus (Fr.) Pat. and Don...
J Van Acker, M Stevens, V Rijckaert
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 20: Report on the inspection of specimens at Sekondi, Ghana after 48 months
1985 - IRG/WP 4116
The results of the second inspection of CCA- and CCB-treated test panels exposed at Sekondi, Ghana, in June 1980, are presented. The panels of Pinus sylvestris treated with 3% CCA are stil unattacked after 48 months. Panels treated with 10% CCA and still in test (Fagus sylvatica, Pinus sylvestris and Alstonia scholaris) are still free of attack. Locol species treated with 3% CCB have all been dest...
F F K Ampong, N Asare-Nyadu
The use of pyrethroids against Limnoria spp
1981 - IRG/WP 473
Synthetic pyrethroid insecticides discovered in the last fifteen years have been developed as crop sprays and used in aerosol formulations for the control of household pests. High toxicity to a wide range of arthropod pests, combined with reasonably low mammalian toxicity, confers an advantage over many other control agents. Some of the more recent pyrethroids are photostable and display residual ...
D Rutherford, R C Reay, M G Ford
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
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 4: Report of second inspection (12 months) in Australia
1979 - IRG/WP 448
Previous reports have presented full details of the treatment and installation of the test specimens in Sydney Harbour during December, 1977, and of the results of the first (6 months) inspection made during June, 1978. At the June inspection it was apparent that the plastic tubing used to make up the frames from which to suspend the specimens was inadequate for the job and not strong enough to su...
J Beesley
Chemical analyses of IRG/COIPM INTERNATIONAL MARINE TEST (to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water) samples
1987 - IRG/WP 4114
Chemical analysis of CCA and CCB treated timber was carried out after exposure at tropical and temperate marine sites. Results indicated that losses of all elements had occurred. In particular, losses of boron were severe. Arsenic and copper were also lost. The chromium components in both formulations was the most dominant metal remaining. The results suggest that chromium modification was importa...
L E Leightley
Initial microbial colonisation of CCA-treated, creosote-treated and untreated Pinus sylvestris L. blocks in seawater
1996 - IRG/WP 96-10171
CCA-treated, creosote-treated and untreated Pinus sylvestris sample blocks were immersed in a seawater through-flow system for periods of between 1 and 265 hours. Samples were fixed immediately on removal and examined both qualitatively and quantitatively using the scanning electron microscope. This study of primary microbial colonisation showed differences between treatments in the diversity of m...
K Sturgess, A J Pitman
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
Effects of heat treatment on water repellence and anti-swelling efficiency of beech wood
2002 - IRG/WP 02-40223
The heating of solid wood to higher temperatures is the simplest and the cheapest means for stabilizing its dimensions. For the investigation of the effect of thermal treatment on water repellency effectiveness and anti-swelling efficiency of beech wood (Fagus orientalis Lipsky), air-seasoned samples of beech wood were heated in presence of air at temperatures of 130 C, 150 C, 180 C and 200 C for ...
S Yildiz
Acceleration of the fixation of chromated wood preservatives by UV-radiation
1989 - IRG/WP 3544
Preliminary laboratory tests demonstrated that the fixation of chromated water-borne wood preservatives may be accelerated by UV-radiation. The degree of fixation depends on the intensity of radiation and the prevailing temperature. Three hours radiation at 20°C in a device for artificial weathering diminished the leaching of chromium to 43% and of copper to 23% compared to not-radiated samples. ...
H M Illner, H Willeitner, K Brandt
A Preliminary Report on the Properties of Engineered Wood Composite Panels Treated with Copper Naphthenate
2005 - IRG/WP 05-40294
This paper reports on our preliminary investigation of the properties of randomly oriented strandboard which had waterborne or powdered copper naphthenate (CuN) incorporated into the board during manufacture. When compared to zinc borate-treated controls (ZnB), the mechanical properties of strandboard (MOR, MOE, work-to-maximum load, internal bond strength) were not adversely affected by treatmen...
J W Kirkpatrick, H M Barnes
Soil-bed studies. Part 2: The efficacy of wood preservative
1983 - IRG/WP 2205
Various methods of decay assessment were investigated. Three stages or phases of decay were identified which could be used to describe the efficacy of a preservative system or virulence of a soil-bed testing medium. These included the lag, decay, and senescent phase. Premature senescence could arise if wood samples became waterlogged. It was concluded that time to failure was unsuitable as a metho...
P Vinden, J F Levy, D J Dickinson