Your search resulted in 721 documents. Displaying 25 entries per page.
Preservative treatment of Eucalyptus saligna fence posts by the double-diffusion method
1982 - IRG/WP 3196
Eucalyptus saligna fence posts treated by the double-diffusion method with two chemical combinations showed average lives of 11.2 years (copper sulphate and potassium dichromate at 10.5 kg/m³ retention)and of 14.3 years (copper sulphate and sodium mono-H arsenate at 7.1 kg/m³ retention), as determined in five test sites in the State of Sao Paulo, Brazil. The exponential model was the best fit wh...
E S Lepage, A R De Freitas
Options for accelerated boron treatment: A practical review of alternatives
1985 - IRG/WP 3329
Boron wood preservatives are almost exclusively applied by momentary immersion and block diffusion storage. Alternative techniques are described which can be used to accelerate boron treatment. Diffusion coefficients have been derived to define the acceleration of diffusion with increasing temperature. Schedules are described for pressure impregnation of green timber, involving steam conditioning,...
P Vinden, T Fenton, K Nasheri
Finite element analysis of boron diffusion in wooden poles
2003 - IRG/WP 03-40263
The problem of describing the migration of dissolved boron in wood is treated with special reference to the commonly used remedial treatment of wooden poles. The governing equations are derived and discussed together with some of the material parameters required. The equations are solved by the finite element method and finally, results showing the effect of different treatment strategies are pres...
K Krabbenhøft, P Hoffmeyer, C G Bechgaard, L Damkilde
Treatment of dried sawn spruce and redwood building timbers with water-borne preservatives under a scheme for the quality control of the preservation and preserved wood in the Netherlands
1978 - IRG/WP 3123
Treatment of dried sawn spruce and redwood Building Timbers with water-borne preservatives under a scheme for the quality control of the preservation and preserved wood in the Netherlands. The aim of this article is to give the reader a modest description of the evaluation of fundamental research in wood preservation into a practical application....
H F M Nijman, N Burgers
The utilization of preserved rubberwood
1982 - IRG/WP 3186
The paper examines the use of processed and kiln-seasoned rubberwood for manufacturing furniture and doors and windows, discusses methods tested and found acceptable for preserving the timber as well as for drying the treated timber in conventional kilns. It considers a type of furniture where narrow width timber of preserved and kilned rubberwood has been used with great success. It recommends th...
V R Sonti, B Chatterjee, M S Ashraf
Diffusion treatment plants (Latin America - Africa)
1974 - IRG/WP 333
B N Prasad
HCB - a new preservative combination for wood pole maintenance
1996 - IRG/WP 96-30122
New combination of heavy creosoted boron (HCB) applied on hardwood and softwood logs at different moisture content revealed successful diffusion of boron in all sapwoods within 7 days and in all sapwoods plus hardwoods within 15 days. The new cost effective paste sterilizes wood through diffusion and suitable for pole maintenance at groundline and above groundline e.g. cut ends, drilled holes, woo...
A K Lahiry
Treatment of messmate (Eucalyptus obliqua L'Hérit) by double-diffusion: Preliminary report
1983 - IRG/WP 3234
Modified double-diffusion is suggested as a method of impregnation for mixed tropical hardwoods for certain types of ground contact use in less developed countries. Compared with vacuum/pressure impregnation, capital costs are low and little skill is needed for the operations involved. Treatment of messmate (Eucalyptus obliqua L'Herit) rounds involving pre-heating in water prior to their ...
F F K Ampong, C-W Chin
Factors affecting the sorption of preservative during diffusion treatment of wood
1988 - IRG/WP 3500
The sorption of preservative into wood during soaking in aqueous solution was found to comprise absorption as well as diffusion of solute. Absorption was increased by partially seasoning the wood prior to soaking and was characterised by (a) a very rapid initial rate of uptake and (b) an extended period of slow uptake, the rate of which varied with prior conditioning. It was concluded that some pa...
Evaluation of a solid remedial wood preservative containing boron and fluorine
1993 - IRG/WP 93-30022
The fungicidal and termiticidal effectiveness of a new rod form of diffusible remedial wood preservative, containing disodium octaborate tetrahydrate/sodium fluoride and marketed as Polesaver Rod, was evaluated in laboratory tests against three species of basidiomycete fungi (Coniophora olivacea, Pycnoporus coccineus, Perenniporia tephropora) and two species of subterranean termites (Coptotermes a...
K J McCarthy, J W Creffield, L J Cookson, H Greaves
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
Study on the treatment of construction timbers by diffusion methods
1983 - IRG/WP 3252
Several species of timber that could be used for constructional purposes have to be pressure impregnated before such use. Pressure impregnation requires expensive equipment, and needs specialized trained operators, etc, which is not possible in most parts of India. Some timbers cannot be pressure impregnated, but can be treated by diffusion. Diffusion treatments could protect these timbers with si...
V R Sonti, B Chatterjee
Ammoniacal wood preservative for use in non-pressure treatment of spruce and aspen poplar. Part 1
1984 - IRG/WP 3273
End-matched lumber of Picea glauca (Moench)Voss (white spruce) and Populus tremuloides Michx. (aspen poplar) timbers was treated by a thermal diffusion process in open tank treating vessels using an ammoniacal copper-arsenate wood preservative. The process proved technically feasible with respect to controlling the vapourization of ammonia from open tanks during treatment at high temperatures. Tre...
C D Ralph, J K Shields
The dip diffusion treatment of tropical building timbers in Papua New Guinea
1972 - IRG/WP 310
In Papua New Guinea a dip diffusion process using a multi salt preservative developed by C.S.I.R.0. has been in commercial use for 8 years. Over 200 million super feet (236,000 m³ ) of timber has been treated during this period and current rate of treatment is 34 million super feet (80,400 m³ ) of timber per year in 70 licenced treatment plants. The process has been found to be simple to apply, ...
C R Levy, S J Colwell, K A Garbutt
Lifetime of impels in poles maintenance cycles for utility poles
2001 - IRG/WP 01-30258
In 1992-98 15.000-20.000 utility poles in Denmark received remedial treatment against decay with fused Boron-rods (IMPEL®). Economically simple, the Impel-rods are placed with the PillarTreat Method as concentrated depots in the ground-line. From there it is distributed by diffusion through the natural moisture in the wood, which ensures that it reaches moist wood in that parts of the pole where ...
A Peylo, C G Bechgaard
Performance of boron and fluoride based rods as remedial treatments in Douglas-fir poles
1995 - IRG/WP 95-30070
Boron and fluoride are widely used for remedial internal treatments, but their use in North America has been limited. Recently, however, interest in these chemicals has increased as the result of concerns about the risks of fumigant usage. The performance of boron or a boron/fluoride combination was assessed in Douglas-fir poles over 1 to 3 year periods. Both chemical formulations diffused well th...
J J Morrell, P F Schneider
A chemical and mycological evaluation of fused borate rods and a borate/glycol solution for remedial treatment of window joinery
1983 - IRG/WP 3225
The possibility of using fused borate rods (Impel Borpatron) and a borate/glycol solution (Boracol-40) for depot impregnation of window joinery has been examined in a co-operative project between The Swedish Forest Products Research Laboratory, The Swedish University of Agricultural Sciences and Prolignum AB. The fused Impel rod is a glassy rod composed of disodium octaborate which readily dissolv...
M-L Edlund, B Henningsson, A Käärik, P-E Dickèr
Boron treatment methods for lyctid susceptible hardwoods growing in Tasmania
1998 - IRG/WP 98-30168
A survey of existing boron plants that treat to protect hardwoods from attack by lyctids in Australia showed that hot and cold bath, and vacuum pressure impregnation (vpi), were the two most common methods employed. In experimental work, two of the treatment methods, vpi and dip diffusion, were used to treat seasoned and green messmate (Eucalyptus obliqua) and blackwood (Acacia melanoxylon). The t...
L J Cookson, D Scown, K McCarthy
Preservative treatment and field test monitoring of spruce pole stock: Pressure and diffusible chemical treatments
1990 - IRG/WP 3605
One hundred and forty four spruce (test species) and southern yellow pine (reference species) poles were variously treated by center boring, incising, or kerfing, followed by pressure treatment with CCA and/or diffusible preservatives. The diffusible preservatives included NaF/creosote, borax and ammonium bifluoride. The poles were set at a test site and evaluated for preservative distribution and...
B Goodell, A J Pendlebury
Optimun storage period for the boron diffusion treatment of rubber wood
1996 - IRG/WP 96-30121
The study determined the maximum thickness of rubber wood that can be diffusion treated and the effect of diffusion storage period on the distribution of chemicals in treated wood of various thicknesses. Wood of thickness up to 50 mm can be easily diffusion treated with 10% boric acid equivalent (BAE) solution to adequate loading of chemicals. The optimum diffusion storage period to get uniform an...
T K Dhamodaran, R Gnanaharan
Preservative treatment of green timber by diffusion
1984 - IRG/WP 3291
The preservative treatment of green timber by diffusion is reviewed together with criteria which influence the economics of the process. New process options are described which should overcome some of the technical and economic disadvantages of double diffusion. These include the use of coagulating agents which increase the viscosity of the preservative solution and facilitate treatment by momenta...
Diffusion of chromium and fluoride in Rentex treated creosoted pole sections
1991 - IRG/WP 3659
A chromated fluoride preservative was applied by injection to the groundline regions of creosoted distribution pole sections and these were erected at a filed site in Scotland. Wood samples were recovered for chemical analysis at one week, two, five and twelve months after treatment. Small sample mass and destructive nature of the analysis necessitated modification of an alkali fusion technique to...
D C R Sinclair, G M Smith, A Bruce, B King, H J Staines
Preservative treatment of wood by diffusion processes - Simulation of commercial treatment processes
1988 - IRG/WP 3498
Spruce (Picea abies), Scots pine (Pinus sylvestris) and birch (Betula pendula) were preservative treated by diffusion with mixtures of copper sulphate and arsenic pentoxide. The preservative was fixed after a suitable diffusion storage period by soaking in ammonia solution. A high standard of treatment could be achieved in spruce sapwood. This was attributed to its low wood density, and high wood ...
Accelerated diffusion treatment of sawn Sitka spruce grown in the UK
1986 - IRG/WP 3395
The treatment of 'green' sapwood and heartwood of Sitka spruce by diffusion methods was investigated. Steam/dip treatment processes gave increased solution uptakes and depths of penetration of copper in comparison with a simple dip treatment. Further investigation is required to reduce diffusion gradients with copper based formulations and to improve the penetration of '...
R J Murphy, D J Dickinson
Ammoniacal wood preservatives for use in non-pressure treatment of spruce and aspen poplar. Part 2
1984 - IRG/WP 3274
A series of thermal diffusion treatments were carried out on unseasoned white spruce (Picea glauca (Moench) Voss) lumber and air dry aspen poplar (Populus tremuloides Michx.) timbers using an ammoniacal copper arsenate wood preservative. Under the specific conditions described, certain charges of lumber met the present Canadian Standards Association Wood Preservation Committee's requireme...
C D Ralph, J K Shields