Your search resulted in 783 documents. Displaying 25 entries per page.
Comparison of variable, constant and fluctuating pressure methods
2001 - IRG/WP 01-40212
The objective of this work was to evaluate potential improvements in pressure treatment arising from the use of a control valve. A constant pressure of 1035 kPa was compared to the conventional variable pressure method where the pressure is allowed to drop to 860 kPa as the solution is absorbed by the wood. A fluctuating pressure method (FPM) where the pressure cycles between 1000 and 1070 kPa was...
S M McFarling, P I Morris
Persistance of active ingredients in treated wood
1993 - IRG/WP 93-50001-20
Disposing of chemically protected waste wood implies the distinction between surface and pressure treatment. Considering that barked round-wood merely contains, after 7 months open storage, less than 30 g per ton of bark or 25 mg per ton of sapwood, depending on the type of insecticide, the bark or sapwood shavings may be incinerated normally, according to less severe legal prescriptions than for ...
E Graf, P Manser, S Rezzonico, B Zgraggen
Adequate preservative treatment of kiln dried Eucalyptus camaldulensis and Acacia mangium for tropical and subtropical wood poles
1996 - IRG/WP 96-40075
The Eucalyptus camaldulensis and Acacia mangium round timbers kiln-dried at EMC and full cell pressure treated with CCA-C ensured requisite penetration and adequate dry retention (30 kg/m³ or 4% w/w). The sufficient inherent strength, seasoning property, treatability of sapwood and heartwood equivalent to 44% of radius, natural durability of heartwood, and field investigation on service performan...
A K Lahiry
Clean creosote - its development, and comparison with conventional high temperature creosote
1983 - IRG/WP 3235
Pigment emulsified creosote (PEC) is presently being tested and shows considerable stability in terms of water content, pigment level, pH, viscosity, rheological behaviour and microscopy. Timber samples from several eucalypt species have been treated with PEC and side matched samples treated with conventional high temperature creosote (HTC). The PEC treated specimens showed higher weight retention...
C W Chin, J B Watkins, H Greaves
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
Studies on the determination of the durability of wooden poles and fence posts
1982 - IRG/WP 3195
This study was carried out by the Forestry Research Institute. 5 Turkish main tree species, Oak (Quercus), pine (Pinus sylvestris), beech (Fagus orientalis) and Fir (Abies bornmülleriana) wooden poles and fence posts, were treated with Tanalith-U and creosote applying pressure process. Tanalith-U was applied by full-cell process and creosote was applied by empty cell process. Treated and untreate...
R Ilhan, O Taskin, A P Erten
The multi-phase pressure (MPP) process. One-stage CCA treatment and accelerated fixation process
- The process as a new concept in preservative treatment
1997 - IRG/WP 97-40078
The background to current commercial CCA treatment schedules used in New Zealand and fixation processing is reviewed. The limitations of these conventional practices with respect to treated product quality and CCA solution handling issues are defined. A novel, patented treatment schedule has been developed using a combination of hydraulic and pneumatic pressure phases and hot (~ 75°C) CCA solutio...
K Nasheri, A J Pendlebury, J A Drysdale, H Pearson, M E Hedley
CCFZ, a new type of water-borne wood preservative for vacuum pressure impregnation
1991 - IRG/WP 3643
By combination of CCF-Salt types with zinchexafluorosilicate a remarkable improvement of efficacy is achieved. In the same time the ecotoxicoligical data become more save. As well as the efficacy against wood-destroying organisms (Basidiomycetes, Soft rot and Long horn beetle) the basic data to evaluate the ecotoxicological behaviour of a CCFZ-Salt are described and compared with the properties of...
W Metzner, D Seepe, H-W Wegen
Preservative treatment specifications in Fiji
1982 - IRG/WP 3190
The preservative treatment specification used in Fiji is outlined. Reference is made to a basic end use classification and to locally approved treatment processes, preservatives and retention levels. Amenability ratings are defined and penetration requirements for broad commodities indicated. Currently commercial operations rely entirely on pressure treatment with copper-chrome-arsenic multisalts ...
A S Alston
Survey of conditioning treatment practices in the Philippines
1975 - IRG/WP 349
The wood preservation industry in the Philippines is at present beset by many problems. An association of the industry similar to those existing in other countries has only been initiated last year by FORPRIDECOM. It is hoped that the formal organisation of this association will bring into focus the importance of this particular industry in the economic and industrial development of the country. L...
R F Casin
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
Internal pressure development in Douglas fir lumber during pressure treatment
1997 - IRG/WP 97-40091
Preservative treatment of Douglas fir lumber to meet current industry standards poses a major challenge and a variety of methods have been developed to overcome these problems. One aspect for treatment improvement that has received less attention is the relative effect of treatment parameters on changes in pressure within the wood. Previous studies of spruce and radiata pine suggest that internal ...
P F Schneider, J J Morrell
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 4. MPP compared with other processes for achieving acceptable treatment of radiata pine heartwood
1998 - IRG/WP 98-40115
Although radiata pine sapwood is very amenable to preservative treatment, it is often difficult to achieve the required standard for heartwood treatment.
A preliminary investigation showed that to achieve the NZ Timber Preservation Council minimum penetration requirements for radiata pine heartwood using the Multiple-Phase Pressure (MPP) Process, a hydraulic pressure of at least 1250 kPa for 20 m...
K Nasheri, J A Drysdale, G Durbin, M E Hedley
Wood preservatives treatment of black spruce
1997 - IRG/WP 97-40092
A representative sample of black spruce logs from Central Newfoundland was harvested and processed to dressed 2"x4" lumber. Over 400 pieces of lumber were then incised and treated with ACQ preservative in a semi-industrial retort. 9 charges of 20 samples were used to determine treating parameters and 11 charges of 20 pieces were treated using the optimized process. This material was inspected by a...
A R Zahora, J P Hösli
Characteristics of thermally modified wood in vacuum
2004 - IRG/WP 04-40287
In commercial thermal wood modification processes nitrogen, steam or oil has been used for the reduction of oxygen content in the reactor atmosphere. In present study no special heating medium, but an initial vacuuming step has been used for this purpose. Mass loss, resistance to fungal decay, dimensional stability, bending strength and modulus of elasticity of heat treated wood were evaluated and...
G Rep, F Pohleven, B Bucar
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
Preliminary pole treatment trials with chlorothalonil in hydrocarbon solvent
1994 - IRG/WP 94-40027
A series of 460-mm long, end-sealed southern pine pole stubs were treated with chlorothalonil in hydrocarbon solvent. Over sixty sections were treated using various combinations of initial seasoning (kiln-drying, steam-conditioning), treating temperature (ambient, 200°F), initial air pressure, and final conditioning (steam flash + vacuum, expansion bath + vacuum, steam distillation + vacuum). Dis...
H M Barnes
Penetration and absorption of water-borne preservatives in conifers from the Western United States: A preliminary report
1988 - IRG/WP 3475
The treatment of most softwoods from the western United States with waterborne chemicals poses a major challenge. Although many of these species are commercially treated with waterbornes, there is considerable debate about their treatability. At present, there is little or no information on the treatability of western wood species with waterborne chemicals. The lack of accurate treatability inform...
S Kumar, J J Morrell
The present status of wooden catamarans of the Indian Coast
1997 - IRG/WP 97-10231
Catamarans (a.k.a. kattumarams) are the most widely used fishing craft in India, and hundreds of thousands of poor, traditional fishermen depend on these vessels for their livelihood that are almost made entirely of wood. In recent years, acute shortages and phenomenal increases in prices of timber species used in catamaran fabrication have been reported, causing great hardship to the user communi...
K S Rao
A bioassay of remedially treated pole material
1987 - IRG/WP 3453
Stubs prepared from treated and untreated utility poles were installed in a test plot and pressure spade treated at the groundline with one of four preservative greases. At one and three year intervals, core samples were removed from the stubs and the improvement in the preservative efficacy due to the greases was assessed. The bioassay investigation showed that only bis(tributyltin) oxide (TBTO) ...
J N R Ruddick, L Parker
Application of paint primers after light organic solvent preservative treatment
1986 - IRG/WP 3381
The application of three alternative paint primers is investigated, including a slow-drying oil-based primer, a fast-drying oil-based primer, and a fast-drying water-based primer. The treatment schedules employed, in particular the evacuation period after treatment, have a marked effect on subsequent paintability. Priming can potentially be carried out immediately after treatment with approved Tim...
P Vinden
Borate diffusion from fused borate rods in douglas-fir transmission poles
1994 - IRG/WP 94-30042
Pressure-treated utility poles have given many years of excellent service, but their lifetime is often shortened by internal decay of the untreated heartwood center, particularly in refractory species, such as Douglas-fir. This paper reports the distribution of boron from fused borate rods installed in CCA-treated Douglas-fir transmission poles. The boric acid equivalent was roughly monitored by t...
T L Highley, W Finney, F Green III
Redistribution of boric acid in radiata pine during drying after preservative treatment
1993 - IRG/WP 93-40010
Samples of 100 x 50 mm² radiata pine were processed with a variety of options to produce dry, boron-treated wood. Concentrations of boric acid in the central one-ninth and in the whole of the wood cross-sections were determined by chemical analysis and compared. Diffusion treated material was dried by air, conventional kiln (70/60°C), or high temperature kiln (120/70°C). Four different predryin...
A J Bergervoet, D R Page, J A Drysdale
Penetration of oil-borne preservatives in American elm
1975 - IRG/WP 355
Pressure treatment of elm posts and cants by Rueping schedules resulted in erratic penetration. Instead of the expected gradual decrease in retention from surface inward in posts, inner zones frequently contained more preservative than the surface quarter inch. Heartwood was found penetrated when sapwood was not. There were numerous skips in treated zones. The prevalence and possible causes were i...
E A Behr
Experimental variations in the distribution of CCA preservative in lignin and holocellulose as a function of treating conditions (temperature, concentration, pH, species, and time)
1984 - IRG/WP 3277
The exact distributions between lignin and holocellulose and retentions on wood of copper, chromium and arsenic as a function of various sets of conditions in a 3x3x4x2 factorial experiment in which combinations of three temperatures of treatment, three CCA solution concentrations, four pH's of the initial CCA solution and two timber species, namely Pinus radiata and Eucalyptus grandis, a...
A Pizzi, E Orovan, M Singmin, A Jansen, M C Vogel