Your search resulted in 35 documents. Displaying 25 entries per page.
Pinus and Eucalyptus fenceposts treated with creosote and solvex tar by hot and cold open-tank process
1987 - IRG/WP 3455
A comparative study of the behaviour of two different wood preservatives, creosote and solvex-tar, was made, using two wood species, Pinus pinaster Ait and Eucalyptus globulus Labill, by the hot and cold open-tank process. Results showed that the creosote behaved better in relation with the uniformity of its distribution in wood. On the other hand, better results were obtained on Pinus for both preservatives.
M V Baonza Merino
Problem of the treatment of dried sawn spruce building timbers with water-borne preservatives. Interim reports for discussion at the 4th Annual Meeting in West Berlin on 27 October 1972
1972 - IRG/WP 311
One of the most difficult technical problems facing the preservation industry is how to improve the treatment of refractory species of timber such as spruce. Its resistance to penetration, even under pressure' precludes its use for more hazardous service situations, and even in less severe conditions a higher level of treatment would be desirable. The importance of this subject led us to look once again at possible ways of improving treatment.
W Liese, J W W Morgan, T Hof, R O Ullevålseter
Creosoted radiata pine by non-pressure methods
1988 - IRG/WP 3486
Posts of Pinus radiata have been impregnated with creosote by immersion for 1, 3, and 7 days, and by hot-and-cold open tank with hot bath temperatures at 40°C and 60°C. On the basis of the retention rates obtained, suitable procedures are described for wood elements that are going to be in ground contact, and an analysis is made of the way in which the variables tested affect the results.
M V Baonza Merino, C De Arana Moncada
Some relationship between physical characteristics and treatability of Bolivian woods
1987 - IRG/WP 3434
Using the available data on physical characteristics of 25 Bolivian woods, some relationships between porosity, specific gravity and treatability (hot and cold open tank process with 5% pentachlorophenol) were analysed. The aim of this report is to give information on technical characteristics of Bolivian hardwoods which have been studied in this country by Centro de Desarrollo Forestal and in Peru by Junta del Acuerdo de Cartagena.
A S Viscarra
Effects of surfactants and ultrasonic energy on the treatment of wood with chromated copper arsenate
1977 - IRG/WP 3108
Sugar pine stakes 1'' x 1" x 16" were treated by a hot-water bath followed by soaking in cold CCA solution for 10 to 30 minutes. A similar number of stakes were treated by a cold-cold bath. Half of the stakes were subjected to ultrasonic energy during the CCA bath. The mean absorption for stakes given the hot-cold bath was 18.52 pcf (297 kg/m³) and 4.64 pcf (74 kg/m³) for those given the cold-cold bath. The rates of absorption were o.323 pcf (5 kg/m³) per minute and 0.053 pcf (0.85 kg/m³) per minute, respectively. The relationship between absorption in pounds per cubic foot (Y) and soaking time in minutes (X); Y = 12.27+0.323 X, was linear and significant. The linear relationship for the cold-cold treatment was poor (r = 0.305). Neither ultrasonic energy, nor its interaction with soaking time, had a significant effect on solution absorption for either the hot-cold or cold-cold treatments. In a second series, the stakes were treated in the CCA solution with a 3-minute dip, a 48-hour cold soak, and Lowry pressure. Half of the stakes were treated in the solution to which a surfactant had been added. The interacting effect of surfactant and method of treatment was significant. The highest absorption was obtained when the specimens were treated with the solution containing the surfactant by the Lowry method, 35.13 pcf (563 kg/m³). In comparison, the absorption was 22.55 pcf (361 kg/m³), 36 percent lower, when surfactant was not used. The surfactant had a beneficial effect on the results of the 3-minute dip, but not the 48-hour soak.
C S Walters
Hot and cold treatment in fence posts of Eucalyptus globulus, Castanea sativa, Pinus nigra and Pinus pinaster
1988 - IRG/WP 3489
An analysis is made of the treatment of fence-posts of Eucalyptus globulus, Castanea sativa, Pinus nigra and Pinus pinaster by hot and cold immersion in creosote. The temperatures of the different treatments were 60, 70 and 90°C. The posts were heated for one hour and then allowed to cool for 21 hours 30 min., and finally reheated for 1 hour 30 min. The greatest absorption rates were recorded in Pinus nigra, the results in Pinus pinaster were close, and in Castanea sativa and Eucalyptus globulus they were clearly lower. The highest penetration rates were recorded in Pinus pinaster, followed by Pinus nigra, Eucalyptus globulus and Castanea sativa. The retentions showed the same pattern as the absorptions, but with smaller differences.
C De Arana Moncada, A M Navarrete
Tar-oil uptake vs time in immersion treatment of short pine posts: A simple technique applicable to rural communities of Papua New Guinea
2012 - IRG/WP 12-40608
Pinus caribaea and Araucaria cunninghamii logs ca. 100 mm in diameter were shortened to lengths 25-30 cm, conditioned to at/below fibre saturation point (FSP) for immersion/dip treatment using a hot- and- cold bath open- tank process. Before oven-drying and subsequent treatment, individual test specimens were numbered, their green weights and volumes, and dry weights recorded for basic density, void volume, preservative uptake and retention determination. The poles were bundled and immersed (dipped) in a drum containing light tar-oil creosote. The tar-oil creosote with pine specimens was heated to boiling for 30 minutes and flames were extinguished with water to allow cooling. The cooling conditions, (dip time period for treatment) varied from 1, 5, 15 and 24 hours. Theoretically, a vacuum was created in wood during heating and when cooled, tar-oil was drawn into the wood’s anatomical structures. The experiment results indicated that tar-oil uptake and retention increased with dip time until available void volume was filled and no further uptake occurred. In this case, the preservative uptake and retention were proportional with square-root of dip time. The technique was simple with basic materials required for hot and cold bath treatment. This treatment technique is more appropriate for application at rural community level for treatment of utility posts/poles.
B K Gusamo, R Tulo
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. Treatments of 48 hours or more on unseasoned and partially dried lumber produced net oxide retentions above that required by the Canadian Standard Association CSA-080 wood preservation standard for timber in above ground contact situations. Although preservative penetrations did not meet the penetration requirements (10 mm), of the CSA 080.2 standard for ground contact, five of the seven non-pressure charges on spruce lumber had heartwood penetrations greater than 7 mm in depth. A 24-hour treatment on air-dried spruce had penetrations equivalent to a five-hour vacuum-pressure treatment. Retention was adequate for above-ground exposure
C D Ralph, J K Shields
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 requirements for wood in ground contact, having 10 mm penetration and 6.4 kg/m³ loading. The average preservative penetration in the heartwood of white spruce lumber ranged from 6.3 mm for charges of nonincised lumber to 13.9 mm for incised lumber. Preservative retention in the treated area was above 6.4 kg/m³ in four of the five charges of spruce lumber treated by this method. Aspen poplar timbers treated by thermal diffusion averaged 16.4 kg/m³ oxide retention. Post-treatment procedures such as close piling the lumber resulted in material with cleaner surfaces and more even penetration of preservative components.
C D Ralph, J K Shields
Preservative Treatment of simul (Bombax ceiba) Veneers with Hot and Cold Water Solution of borax-boric acid by Soaking Process
2010 - IRG/WP 10-40528
Veneers of simul (Bombax ceiba) were treated with different concentrations of water- borne preservatives borax-boric acid (BB) by soaking process for different time periods. In the case of hot water treatment, it was found that the average retention of preservative chemicals increased gradually with the increasing treatment period from 20 minutes to 60 minutes. Similar trend was observed in the case of cold water treatment when treatment period was increased from 1 day to 3 days. The maximum retention (20.37 kg/m3) was observed from the samples treated with 10% BB solution for 60 minutes and in 2.5% BB treated samples, the average retention gradually increased from 5.35 kg/m3 to 7.16 kg/m3 when treatment duration was varied from 20 to 60 minutes. In the case of cold water treatment, maximum retention (22.97kg/m3) was observed from the veneers treated with 10% BB solution for 3 days and 7.35 kg/m3 retention was obtained when treated with 2.5% Borax-boric acid solution for 1 day. According to the Indian Standard (IS-1902), the retention of 4 kg/m3 boron compounds are sufficient to offer protection for non-structural purposes.
K Akhter, Md Abul Hashem, S Akhter
Dimensional stability and decay resistance of hot-melt self-bonded particleboard by surface benzylated pine chips
1991 - IRG/WP 3652
Akamatsu (Pinus densiflora Sieb. et Zucc: Japanese red pine) particles were pretreated with 40% NaOH solution and benzylated with benzyl chloride, and the surface of particle was converted into meltable materials. Hot-melt self bonded particleboard having smooth and high glossiness surface was prepared by hot pressing at 150°C and 1.96 MPa without using any conventional adhesives. Dimensional stability and decay resistance of the benzylated particleboard were evaluated. Particleboards made of benzylated particles having more than 38% of weight percent gain (WPG) showed that dimensional stability and decay resistance were superior to the conventional particleboard made by using phenolformaldehyde resin as a binder, because hydroxyl groups of wood were substituted by hydrophobic benzyl groups with benzylation. Though bending strength of the board was a little lower than control board due to the damage of benzylated particles during benzylation, its internal bonding strength was very high, because the hot-melting strengthened the inter-particle bonding.
M Kiguchi, K Yamamoto
The decay resistance of chemically modified aspen composites to the white rot fungus Coriolus versicolor (L.) Quelet
1998 - IRG/WP 98-40122
Chemical modification of Aspen wood (Populus tremula L.) in the form of solid wood, veneers and sawdust was undertaken by a two step procedure consisting of esterification with maleic anhydride (MA) and subsequent oligoesterification with MA and glycidyl methacrylate (GMA) or allyl glycidyl ether (AGE). Modified wood was thermoplastic and was thermally formed by hot-pressing to produce veneer or solid wood samples with smooth glossy surfaces, while plastic-like wafers were obtained by hotpressing modified sawdust. Chemical modification alone was shown to enhance the biological resistance of Aspen to decay by Coriolus versicolor. In addition, hot-pressing enhanced decay resistance of both unmodified wood and esterified wood veneer samples, although no improvement was found by hot pressing oligoesterified wood. The most effective treatment for the improvement of decay resistance was chemical modification of the sawdust in conjunction with hot-pressing. A microscopic examination of chemically modified and control samples following exposure to the fungus showed more extensive colonisation and decay in untreated, unpressed samples.
M C Timar, A J Pitman, M D Mihai
Effect of a penta emulsion on the service life of Douglas fir, heartwood posts
1978 - IRG/WP 3112
C S Walters
An Open Letter to Proponents of CLT/Massive Timber
2016 - IRG/WP 16-40755
We present an Open Letter that discusses the need to address the potential for biodeterioration in CLT/Massive timber structure. We invite members to review and sign the document. We also welcome suggestions for potential recipients.
A Taylor, J Lloyd, T Shelton
Proposal for co-operative work. Testing the ability of accidentally introduced tropical insects to survive the cold season in Europe
1976 - IRG/WP 155
By hibernation-experiments in the past it was found that not only the low temperatures may become fatal by freezing. In some experiments we found indications that larvae died by starvation. For example Lyctus africanus-larvae did so in some years with a cold winter (mean above 0°C). If you like to take starvation as a reason for death into account it may be useful to withdraw pieces of infested wood after different times of hibernation or to add new material later.
Termite and decay protection - A superficial barrier field test
1983 - IRG/WP 3257
Samples of Pinus radiata were given a superficial barrier treatment and installed in the ground at two sites for five years to observe termite and fungal attack. The three best treatments of the series were Denso petroleum tape, Koppers hot dip tar enamel, and Arquad 2C/75 alkyl ammonium compound. As new fungicides and insecticides become available they are being added to the test using the same system of treatment and exposure.
R S Johnstone, W D Gardner
Laboratory simulation of leaching from creosote treated wood in aquatic exposures
2000 - IRG/WP 00-50157
Creosote has a long history of use as a preservative particularly in industrial wood products, but its use has come under increasing scrutiny as a result of concerns about its potential effects on aquatic and terrestrial non-target organisms. Despite its long use, there is relatively little data on the rates of creosote loss in many exposures. In this report, we describe small scale leaching tank procedures for evaluating migration from creosote-treated Douglas-fir lumber exposed at 35°C under 0 flow rate conditions. Creosote component concentrations in the water column were quantified using solid phase microextraction and gas chromatography. As expected, migration rates were higher for lower boiling point fractions. Leaching in the first eight hours followed a linear relationship for acenaphthene, dibenzofuran, fluorene, phenanthrene and fluoranthene. Chemical concentrations arrived at a steady state after 24 hrs of leaching. Concentrations of all creosote components tested tended to be lower than their reported water solubilities, suggesting that other factors were influencing migration. Further analyses of the leaching system are planned. The results will be used to expand a model that simulates creosote loss from treated wood in flowing fresh water.
Ying Xiao, J Simonsen, J J Morrell
Remedial treatment of wood attacked by insects
1981 - IRG/WP 3175
A review is presented of remedial treatments against wood-boring insects in wood in service. Preconditions and fundamental principles of insect control are compared with the control of fungal attack and reasons are given for the fact that remedial treatments against insects are more commonly applied than against fungi. With regard to insect control measures with a simultaneous preventive effectiveness, information is given on preservatives, control measures as well as on testing the effectiveness of preservatives with eradicant action. An evaluation of 40 tests according to EN 22 or DIN 52164 revealed that a mean depth of effectiveness of 15 mm is obtained at mortality rates of 80-84% of Hylotrupes larvae. At a mortality rate of below 75% the mean depth of effectiveness was about 10 mm and above 90% it was about 27 mm. Among the control measures without any preventive effectiveness fumigation and hot-air treatments are referred to. With regard to biological control measures, practical results are not yet available.
The shower test method. A leaching test for assessing preservative losses from treated timber under simulated open storage conditions
1993 - IRG/WP 93-50001-04
In the late 1980's against the background of increasing environmental concern a laboratory based accelerated leaching test method for assessing preservative losses-from stored, treated timber was developed by the Dutch organisation for applied Scientific Research (TNO). This test method quantifies the amount of specific preservative components which leach from treated timber under simulated open storage conditions. The test method measures leaching from both creosote and inorganic salt treated timber. Leached components are quantified in relation to their retention in the treated product and described by use of a leaching factor. The test allows for the direct determination of leachates as a function of time (i.e. fixation) and enables the influence of several material and process variables to be assessed. This test is currently being used, under Dutch legislation, as an environmental control system for the Dutch wood preservation industry.
J B G A Havermans, W J Homan, M J Boonstra
Properties of hot oil treated wood and the possible chemical reactions between wood and soybean oil during heat treatment
2005 - IRG/WP 05-40304
Thermal treatment with hot oil as the heating media based on the original idea from oil-heat treatment in Germany was investigated. The treatment was mainly carried out at 200ºC and 220ºC for 2 hours and 4 hours, and the wood species were mainly spruce and fir. This paper focuses on the difference between soybean oil and palm oil and the possible chemical reactions between wood and soybean oil. Generally palm oil was slightly better than soybean oil in improving the moisture resistance properties of heat-treated wood. But soybean oil treated wood appeared to have better decay and mould resistance. The mass loss of wood treated in soybean oil at 220ºC for 4 hours was below 20 % after exposure to Gloeophyllum trabeum in a soil block test, so the treated wood can be classified as “Resistant” according to ASTM D 2017 standards. Natural weathering exposure also shows that soybean oil treated wood is more mould resistant than palm oil treated wood. In order to investigate the effects of absorbed oil on the properties of treated wood and the possible reactions between wood and oils, extraction of different vegetable oil treated wood with chloroform and other solvents was carried out. The results suggest that part of the soybean oil could undergo chemical reactions with wood that renders it of low extractability.
Jieying Wang, P A Cooper
Does Limnoria lignorum (Rathke) or other cold-water xylophagous limnoriid species exist in southern oceans?
1989 - IRG/WP 4152
The question is posed whether the cold-water limnoriid wood borer Limnoria lignorum (Rathke), or any other such cold-water limnoriid exists in southern oceans. The evidence of collections from various high latitude southern coastlines is cited and the singular absence of any cold-water limnoriid borer noted. The need for further. and possibly extensive, searches for such borers is stressed. i.e. if their existence in - or absence from - the southern oceans is to be resolved. The questions posed could be relevant to the wood treating industry because of the indicated capacity of Limnoria lignorum, at least, to attack some treated wood.
J E Barnacle, L J Cookson
The wood-attacking insects in wooden houses of an old open air museum in southern Finland
1989 - IRG/WP 1409
Harmful insects of wood in a open-air museum were investigated in 1985-1988 by order of the National Board of Antiquities and Historical Monuments of Finland in nine old log houses. Many thousands of insects and altogether 1073 anobiids (Coleoptera, Anobidae) were obtained by window and light traps. The most common Anobiidae-species were Hadrobregmus confusus (Kraatz) 60.3%, Hadrobregmus pertinax (L.) 30.6% and Ernobius mollis (L.) 8.9%. The amounts of trapped insects varied in different houses and the flight time of anobiids varied greatly according to yearly weather conditions.
H Viitanen, M Pulkkinen
Acceleration of boric acid uptake into the subterranean termite, Coptotermes formosanus Shiraki using steamed larch wood
2000 - IRG/WP 00-10353
Laboratory tests were done to measure the efficacy of addition of steamed larch (Larix leptolepis (Sieb. et Zucc.) Gord.) heartwood extracts for the uptake of boric acid against the termite, Coptotermes formosanus Shiraki. Paper discs were treated with the water-soluble fraction obtained from hot-water extracts of steamed larch wood (S-Water) with or without 0.01-2.0% boric acid, followed by exposure to this of termites, C. formosanus. The consumptions of the discs, termite mortalities, and boron contents in the termite bodies were measured. The S-Water significantly accelerated the consumptions of the discs at the retentions of boric acid below 0.1% (w/w) (p<0.01). However, regardless of the addition of the S-Water, the termite mortalities were almost the same at all the retentions of boric acid examined after 21 days of exposure. When the paper discs treated with the S-Water and 2.0% boric acid were given to workers and soldiers, boron contents in workers were lower than those of the same experiment without soldiers (p<0.01). This is because ingested boron was incorporated into soldier bodies from workers by trophallaxis. In the experiment using only workers, boron contents of termites fed with 2.0% boric acid plus the S-Water were larger than those of the termites fed without the S-Water. From the result, it was supposed that the S-Water inhibited the excretion of boron from the termite bodies or increased the accumulation of it in the termite bodies.
W Ohmura, S Doi, S Ohara
Main problems of Turkish wooden boat manufacturers
1982 - IRG/WP 485
The best transportation system to the eastern Black Sea region of Turkey has been since the earliest history sea transportation. As is well known the historical 'silk road' from Europe to the Far East and China was over the Black Sea and via Trabzon. During the last five years also this same connecting route has become very important for the transportation of food and industrial products from the West to the Middle East. Two other factors that are influencing the building of boats in this region are the local rich forest resources and fishing facilities. It can be pointed out that 80% of the Turkish sea food is produced in the Black Sea region, which amounts to 380,000 tons per year. Therefore the main purpose of boat building in this area can be attributed to the needs of the fishing industry
Study on leaching of a magnesium fluorosilicate product (SF salt) from wood-boards by rain in the open and by artificial shower
1976 - IRG/WP 264
The test was performed in 1961 to obtain information about (1) the comparative leaching effect of natural rain and of artificial shower in the laboratory; (2) the comparative leaching effect on the active ingredient in proportion to the dye-stuff of the product. The results show that a continuos light rainfall with low precipitation has a much stronger leaching effect than short heavy showers with high precipitation. Thus the time of moistening with water flowing on the wood surface is the most decisive factor. The salt is not only washed off by rain but also transferred into the wood. This explains the relative resistance to leaching of a varying amount of salt with longer periods of exposure. The dye-stuff used fades away by leaching and light. much faster than the active ingredient.