Your search resulted in 286 documents. Displaying 25 entries per page.
Field trial with poles of Scots pine treated with six different creosotes
1996 - IRG/WP 96-30115
In the middle of the 50's field trials with creosote-treated poles were started in France, Germany and Sweden. The trials were initiated by WEI (Western-European Institute for Wood Preservation). Six different creosotes were used and 40 poles per creosote were installed at each test field. Results after 39 years of exposure in Simlangsdalen, Sweden are reported. Poles treated with a heavy creosote were less decayed than poles treated with medium-heavy creosotes. Poles treated with a light creosote were most decayed.
A case study on quality control on telephone poles as a cost saving tool in Tanzania
1987 - IRG/WP 3418
A sample of 28 CCA treated Eucalyptus poles from a lot of 2,000 poles awaiting delivery to the field, was studied to reveal the quality of treatment. Results showed a product of very poor quality. Average figures for penetration and retention were 8.4 mm and 2.2 kg/m³; these results are 66% and 91% below the required standards, respectively. Consequences of such results are estimated to amount to losses of billion of shillings.
K K Murira
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
Marine borers as wood degraders in Bangladesh and their protection
1996 - IRG/WP 96-10186
Field study on timber piles used in Bangladeshi brackish waters revealed that untreated and pentachlorophenol treated piles drastically degraded by the attack of molluscs and pholads (marine borers). Adequately CCA-C impregnated (30 kg/m³ or 6% W/W dry oxide retention) timber piles can protect the attack of molluscs. It is very difficult to protect pholads which can invade naturally very durable timbers. Adequately preservative treated piles can be protected from pholads by hardening the initial surfaces by noncorrosive metal plates or by cement. Use of only dense and hard timber species would be a solution.
A K Lahiry
36 years of wood preservative tests in Tanzania
1992 - IRG/WP 92-3731
The performanee of major wood presevatives which are used widely commereially are given. These include creosote, CCA's and 5% Pentachlorophenol dissolved in heavy industrial diesel. Tests are conducted at three ecologically different using pine stakes. Results show that the striking performance of creosote and CCA's is noticeable at above 128 kg/m³ and 16 kg/m³ respectively.
K K Murira, P F Nangawe
Creosote immersion treatments in fence-posts of Castanea sativa, Pinus nigra and Pinus halepensis
1988 - IRG/WP 3488
The method of soaking in creosote was applied to fenceposts of Castanea sativa, Pinus nigra and Pinus halepensis, taking into account its easy use in the field. Absorption, retention and penetration rates were recorded and analysed. Absorption rates were higher in Pinus nigra than in Pinus halepensis, and lowest in Castanea sativa. Thin fence-posts always absorbed more preservative than thick ones. Penetration rates were similar in both pines, and much higher than in Castanea sativa. Retention levels were almost the same in Pinus nigra and Castanea sativa, and lower in Pinus halepensis.
C De Arana Moncada
Butt-end incising to improve penetration and retention of creosote in Eucalyptus saligna power transmission poles in Kenya. Preliminary results
2002 - IRG/WP 02-40249
Incising as a possible technique to improve penetration and retention of creosote in the butt end of Eucalyptus saligna power transmission poles in Kenya was investigated. Debarked, butt-end samples from whole poles were seasoned (15% MC), incised using four patterns of incisions, sealed at the top or small diameter end, and pressure treated with a mixture of creosote-furnace oil (60/40 mix) at a commercial plant using a full cell process. They were then conditioned in the open for 3 months to allow evaporation, migration, and bleeding. The samples were subsequently leached in running tap water for 21 days, air-dried for 8 weeks under cover and retentions calculated on a weight-gain basis and compared. Discs were removed from the middle (450mm) of the samples, and radial penetration assessed visually and measured. Compared to un-incised samples, both penetration and retention were substantially improved in samples with closer incisions of 20 mm x 20 mm, by 58.6% or 89.8 mm and 87.0% or 146.4 Kg/m3 respectively. Wider incisions 0f 40 mm x 40 mm achieved lower improvements, 17.3% or 66.4 mm for penetration and 19.8% or 93.8 Kg/M3 for retention. The 4 incising patterns achieved consistently higher penetration and retention of creosote compared to un-incised control samples, which achieved lower average penetrations (56.6mm) and retentions (78.3Kg/M3). Butt-end, or incising the ground-contact sections of transmission poles may be a feasible technique for improving both penetration and retention in the more vulnerable portions of poles, and thus substantially increase service lives of eucalyptus poles in the country. Further investigations are necessary to establish patterns of incision and appropriate treatment schedules.
Incising to improve penetration and retention of creosote in small-diameter Kenyan-grown Cypress (Cupressus lusitanica)
2003 - IRG/WP 03-40253
Turning small-diameter plantation thinnings into value-added products has remained a challenge in many countries, including Kenya. The present study reports on a feasible technique to effectively treat small-diameter cypress for use in ground contact. Samples of pole-size Cypress (Cupressus lusitanica), 106 mm and 138 mm in average diameter, were sampled from thinnings in 7 and 12 year-old plantations, 2.0 m posts removed from butt-ends, debarked, air-dried to 15% moisture content, subjected to four patterns of incising and pressure-treated with creosote (60:40 creosote/furnace oil mix) at a commercial treatment plant. Un-incised controls were prepared and treated in the same fashion. All samples were then conditioned for 48 days under cover, leached in running tap water for 20 days, air-dried to 15% MC and final retentions calculated on a weight-gain basis. Discs were removed from the middle portions of the samples and average radial penetration measured. The results indicated that the closer the incisions (20 mm x 20 mm), the higher the average retentions (86.3 and 80.8 Kg/m3) and penetration (16.8 and 13.9 mm) in 7 and 12 year-old posts respectively, acceptable for ground exposure situations. Un-incised controls recorded lower average retentions (38.9 and 37.4 kg/m3) and penetration (6.8 and 5.8 mm), sub-standard for poles and posts for ground contact usage. Incising as a technique to obtain the required retention and penetration for cypress small-diameter fencing posts and utility poles is viable, and should be refined and investigated further, together with an appropriate treatment schedule. An effective treatment technique is necessary to allow utilisation of a substantial volume of small-diameter cypress removed as thinnings and normally considered as waste in this country.
Creosote for wood preservation
1971 - IRG/WP 36
By creosote one usually means coal tar creosote, although there are creosotes of other origin. For example, wood tar creosote is a product of wood distillation. It is, in fact, in this connection that the word 'creosote' was first used. Early in the nineteenth century the oily product obtained by distilling wood was said to have an odour which resembled 'smoked meat'. The name creosote was derived apparently from the Greek words 'kreas' meaning meat or flesh and 'soter' to save or preserve. The value of coal tar creosote as a wood preservative was originally suggested in 1836 by the German chemist Franz Moll (British Patent 6,983) who gave the substance its name, although as early as 1716 the American Dr William Crook, who took out the first wood-preserving patent recorded in the United States, had advocated a preservative which contained "the Oyle or Spirit of Tarr" for preserving ships' planking against shipworm and decay. It was John Bethell in 1838, however, who promoted its wide spread use by his patent for the impregnation of timber with tar oils, including the newly discovered creosote, by means of vacuum and pressure (British Patent 7,731). Since Bethell's full-cell process was invented, coal tar creosote has been used extensively throughout the world for the preservative treatment of timbers for various purposes, such as railway sleepers, electricity and telegraph poles, fence posts, farm timbers, cooling towers, and marine timbers. Consequently the literature on this subject is extensive and, to some extent, repetitive so that for practical reference purposes it is essential that selective surveys and bibliographies be prepared. Many of these exist such as, for example, the reports (Numbers 0156, 0292 and 0396) issued by The Coal Tar Research Association, England. The following bibliography, listing the more important sources of information on coal tar creosote and its use as a wood preservative, has been prepared by Working Group III of The International Research Group on Wood Preservation and is based on the CTRA reports and also on a list provided by the Bundesanstalt für Materialprüfung in Berlin-Dahlem. The bibliography is preceded by introductory remarks on the various aspects highlighting important points and suggesting topics for further research work.
Treatability of waterstored poles of Norway spruce by sap-displacement and pressure treatment with Boliden K33 and creosote
1973 - IRG/WP 328
Poles of windthrown Norway spruce were stored in bark under water sprinklers for 11-20 months or fully submerged in a lake for 3 years (tab. 1 and 2). Water content after storage is shown in fig. 1 and 8. Treatment with Boliden K33 by sap-displacement (open tank suction) gave a poor result. The Danish requirements of delivery claim a penetration of 20 mm and a net retention of 12 kg/m³ in outer 20 mm sapwood. According to that 22% of the poles stored for 11 months, 53% of those stored for 20 months under water sprinklers and 67% of those waterstored for 3 years were rejected compared with 11% in both control series (tab. 3 and 4). There was no correlation between water content in outer sapwood before treatment and penetration/retention neither for stored nor for unstored poles (fig. 2-7 and 9-10). Pressure treatment (full-cell) of water stored poles with Boliden K33 after air-drying to app. 28% gave a similar poor result (tab 5) while pressure treatment (Rueping) of water stored poles with creosote gave very good penetration as well as retention (tab. 6). The hypothesis is put forward, that the main reason for the unsatisfactory result of the treatment with Boliden K33 might be coagulation of the bacterial slime when mixed with the salt blocking the pathways for the liquid, although the membranes in the tori and the parenchymatic cells are supposed to have been partly destroyed by the bacteria.
P Moltesen, E Borsholt, B Bang
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 performance of similar hardwood poles treated with CCA-C, pentachlorophenol and creosote ensured their longterm use as tropical and subtropical poles.
A K Lahiry
Influence of different treatment parameters on penetration, retention and bleeding of creosote
2003 - IRG/WP 03-40255
Creosote is an extensively used preservative for transmission poles and sleepers. The purpose of this research was to investigate the treatment parameters necessary to achieve full sapwood penetration and minimum required retention and to avoid bleeding of creosote. It was carried out as a part of the European research project WOODPOLE. Transmission poles of Scots pine (Pinus sylvestris L.) previously air-dried under a roof, were creosote treated in a research plant. Before treatment each pole was cut into three pieces (logs). Each pole made a charge. The creosotes WEI type B and type C were used. A number of treatment processes were carried out using five poles per process. Different levels of pre-pressure and oil pressure were used as well as different duration of oil pressure. Heating of the logs in creosote before pre-pressure and after oil pressure was carried out for one or three hours. Retention was measured by weighing before and after treatment and by analysis. Processes with no or only a short period of heating before pre-pressure and after oil pressure showed most bleeding. Poles and stakes with different levels of retention were produced for field trials.
Conforming to European standards on preservative treatment
1998 - IRG/WP 98-20150
New European standards require that specifications for the preservative treatment of timber are written in terms of the penetration and retention of preservative within the treated commodity that result from the treatment process. In order to check compliance with this type of specification, suitable methods of quantitative analysis must be available. This paper presents the results of a study by BRE and four commercial companies on the methods currently used in the UK to quantify the retention of CCA and creosote in treated timber. When analysing CCA-treated wood, different retention values were obtained with different methods of analysis and even with the same method when different operating parameters were selected. It has been concluded that either a single agreed method of analysis for CCA within Europe is required or more precisely defined operating conditions are required for each instrumental method which includes a method verification procedure. Data from traditional methods of assessing retention of creosote in transmission poles (e.g. charge volume uptake and weight differences) did not coincide with retention values obtained by quantitative analysis using the method in the European prestandard proposed as the reference method for creosote retention determination. Direct quantitative analysis of creosote treated timber selected from single charges showed large variations in creosote retention. It was concluded that recommendations for sampling in EN 351-2 do not take proper account of retention variations within a treated component nor of the difficulty in obtaining an analytical sample from a component once selected for examination. Greater care should be taken in defining the location within a component from which an analytical sample should be taken. In addition, a representative value for density is required in order to convert preservative content, determined as m/m from analysis, to the units used to express retention (kg/m3). This cannot easily be obtained and it is recommended that retention be expressed in m/m terms.
E D Suttie, R J Orsler
Comparative studies on penetration and retention of CCA (C) and creosote in wood from APHID-killed and sound Kenyan-grown Mexican cypress (Cupressus lusitanica)
2006 - IRG/WP 06-40352
Properties of wood from Kenyan-grown Mexican cypress (Cupressus lusitanica), attacked and killed by the cypress aphid (Cinara cupressi), in terms of density and treatability, were investigated in comparison to the properties of wood from sound trees. Density in small wood samples from aphid-killed trees was found lower than density in samples from sound trees, and reduced with tree age in samples from both. However, differences were slight, being 3.8%, 2.5% and 2.3% lower than density in samples of sound trees aged 10, 12 and 14 years respectively. Conversely, penetration and retention of both CCA and creosote were higher in samples from aphid-killed trees of the 3 age classes. Along the grain penetration of CCA was higher by 3.6%, 4.5% and 6.2%, and across the grain penetration higher by 3.8%, 7.0% and 11.3% in samples from aphid-killed trees of the 3 age classes respectively, compared to penetration achieved in samples from sound trees. Higher penetration of creosote in samples from aphid-killed trees was in the order 3.9%, 5.8%, 7.1% along the grain, and 3.7%, 6.2%, 11.9% across the grain. Along the grain retention of CCA in samples from aphid-killed trees was higher by 1.2%, 1.5%, 2.0%, and across the grain higher by 5.1%, 6.3% and 7.4% for the 3 age classes. Similarly, retention of creosote in samples from aphid-killed trees of the 3 age classes was higher by 3.2%, 4.5%, 5.6% along the grain, and 2.6%, 3.2%, 4.6% across the grain. Differences in density and treatability could not be properly explained, but was assumed associated with extensive sap depletion by aphids, interference with tree growth and normal wood formation, hence lowering of wood cell wall materials and increased cellular spaces within the wood cell wall structure of wood from aphid-killed trees. However, the results revealed that differences between wood from aphid-killed and sound C. lusitanica were minimal, and did not warrant wood from aphid-killed trees being branded as of lower quality, and restricted end uses.
R Venkatasamy, F M Opar
The influence of different creosote process parameters on penetration, retention and bleeding on glulam
2007 - IRG/WP 07-40368
Different process parameters were used to treat Scots Pine glulam beams with creosote. Parameters like pre-heating, pre-pressure time, pressure and pressure time were changed. Most treatments gave a full or almost full penetration of creosote into the sapwood, but the uptake of creosote in the sapwood varies. All samples, except the one with poor penetration, showed heavily bleeding of creosote for about a year before the creosote hardened. To get a good protection of the glulam without bleeding, it has to be double-treated. The lamellae have to be copper impregnated before gluing and the beam must then be treated with a creosote process as C (short pressure time) in part 1. The inner sapwood that will be untreated with creosote will then be protected by the Cu-preservative.
F G Evans
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
Biological screening assays of wood samples treated with creosote plus chemical additives exposed to Limnoria tripunctata
1980 - IRG/WP 408
Laboratory methods for exposure of treated wood coupons to Limnoria tripunctata are described. Chemical additions to creosote were screened using this method. Three pesticides, Endrin, Kepone, and Malathion proved particularly effective. The addition of varying percentages of naphthalene to creosote using several treatment methods are currently being assayed. Results to date show that the coupons treated by the empty cell method have better performance than those prepared by the toluene dilution method. The naphthalene coupons treated by the full cell method show no attack after six months' exposure.
B R Richards, D A Webb
Fire resistance of preservative treated fence posts
1994 - IRG/WP 94-30033
Pine fence posts were pressure treated separately with CCA-C, CCA-wax, CCA-oil and creosote. Treated posts and untreated controls were planted in the ground in a randomised block design, weathered for six months and then subjected to a controlled burning test using two fuel loads. Creosote treatment increased the time that posts were alight whereas CCA treatment had no such effect. However, CCA treated posts smouldered until destruction of the majority of the posts occurred. Posts treated with CCA-oil took longer for destruction to occur than posts treated with CCA-C or CCA-wax. Creosote treated posts and untreated controls did not show prolonged smouldering and consequently were not destroyed by the burning test, although their strength was reduced. A high fuel load increased the time that posts were alight and smouldering, and for CCA treated posts decreased their time to destruction.
P D Evans, P J Beutel, C F Donnelly, R B Cunningham
Performance of treated fence posts after 6 years in five test plots in the State of Sao Paulo - Brazil
1976 - IRG/WP 376
Fence posts treated with creosote, pentachlorophenol and creosote/ pentachlorophenol mixtures showed good performance after 6 years of exposure in five test plots located in the State of Sao Paulo - Brazil. Good results were also achieved with copper sulphate/sodium arsenate and copper sulphate/potassium dichromate mixtures. Fungi and termites were the main destroying agents found attacking the posts.
M S Cavalcante
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
Results of chemical analyses in the field of wood preservation in the Bundesanstalt für Materialprüfung
1973 - IRG/WP 321
The results of qualitative and quantitative chemical analyses of wood preservatives are often the basis for evaluating the various works in the field of wood preservation. In the past 10 to 15 years a number of such works was carried out in the Bundesanstalt fur Materialprüfung, Berlin-Dahlem, dealing with the identification and effectiveness of wood preservatives and with methods of wood preservation. Fundamental realisations were made which will be summarised below. It seems advisable to differentiate between inorganic and organic chemical wood preservatives and methods of analyses. These are two distinct fields which differ also with regard to the analytical techniques applied.
H J Petrowitz
Results of stake tests on wood preservatives (Progress report to 1974)
1975 - IRG/WP 361
A number of field stake trials on preservative-treated wood have been carried out at Princes Risborough Laboratory from 1928 to the present day, and many of the tests still continue. This paper presents in detail the results obtained to date, covering about 15 000 individual test stakes exposed over the period.
D F Purslow
Evaluation of new creosote formulations after extended exposures in fungal cellar tests and field plot tests
2000 - IRG/WP 00-30228
Although creosote, or coal tar creosote, has been the choice of preservative treatment for the railroad industry since the 1920s, exuding or "bleeding" on the surface of creosote-treated products has been one incentive for further enhancements in creosote production and utility (Crawford et al., 2000). To minimize this exuding problem, laboratories such as Koppers Industries Inc., USA, and Commonwealth Scientific and Industrial Research Organization (CSIRO), Division of Chemical and Wood Technology, Melbourne, Australia, have developed changes in processing of coal tar that produce distillates with fewer contaminants. This "clean distillate" is then used to formulate "clean creosote" as a preservative. These new, unique creosote formulations are being investigated as part of a program to enhance the use of regionally important wood species in the United States. Four retention levels of each of two new creosote formulations creosote, one pigment-emulsified creosote (PEC) and one creosote formulation that meets the AWPA Standard C2-95 for P1/P13 creosote (AWPA, 1995a), were applied to two softwood species and two hardwood species. Two laboratory procedures, the soil-block and fungal cellar tests (accelerated field simulator), were used to evaluate the four creosote formulations. These procedures characterized the effectiveness of the wood preservatives. The soil-block tests were used to determine the minimum threshold level of the preservative necessary to inhibit decay by pure cultures of decay fungi. In general, the soil block tests showed there was little difference in the ability of the four creosote formulations to prevent decay at the three highest retention levels as summarized in a previous report by Crawford and DeGroot (1996). The soil-block tests will not be discussed in this report. Fungal cellar tests expose treated wood to mixtures of soil-borne fungi that promote accelerated attack. Crawford and DeGroot (1996) discussed the evaluation of the creosote formulations after 17 months of exposure in the USDA Forest Service, Forest Products Laboratory (FPL), fungal cellar. At that point in time data from the fungal cellar tests showed that softwoods are protected better than hardwoods for all four formulations of creosote tested. This report will discuss exposure of the fungal cellar stakes upto 36 months. In addition, field stake tests are being used to verify service life of the new creosote formulations in vivo. Results from accelerated tests are indicative of field performance, but the correlation between laboratory and field results is still being investigated. Field stake tests are regarded as critical, long-term evaluations that provide results most directly related to the performance of treated products in service. In this study, we report on the performance of the creosote formulations after five years of exposure in field tests.
D M Crawford, P K Lebow, R C De Groot
Electrodialytic remediation of creosote and CCA treated timber wastes
2002 - IRG/WP 02-50190
There is a growing concern about the environmental issue of impregnated timber waste management, since an increase in the amount of waste of treated wood is expected over the next decades. Presently, no well-documented treatment technique is yet available for this type of waste. Alternative options concerning the disposal of treated wood are becoming more attractive to study, especially the ones that may promote its re-use. Inside this approach, the electrodialytic process (ED) seems a promising technique for removal of preservative chemicals from treated wood waste. The method uses a direct electric current and its effects in the matrix as the “cleaning agent”, combining the electrokinetic movement (mainly due to electromigration, but also electro-osmosis and electrophoresis), with the principle of electrodialysis. This work reports results from the application of the electrodialytic process to an out-of-service Portuguese creosote and CCA-treated Pinus pinaster Ait. railway sleeper and pole. The behaviour of the process is described and the main results discussed. The average removal rate, estimated in accordance with prEN 12490, for creosote from treated timber waste was around 40 %.. For CCA treated timber waste, experimental conditions that could optimise the process efficiency (e.g. current density, time) were studied. The highest removal rates obtained until now, in our studies, were 93 % of Cu, 95 % of Cr and 99 % of As for sawdust using 2.5 % oxalic acid (w/w) as the assisting agent. For CCA treated wood waste in the form of chips, the best removal rates obtained until now were 84 % of Cu, 91 % of Cr and 97 % of As.
E P Mateus, A B Ribeiro, L Ottosen
Extending the useful life of creosoted electricity distribution poles in service
1993 - IRG/WP 93-50001-16
Creosoted transmission poles have provided good service over many decades in a whole range of environments. The use of save biocides for secondary treatments has the potential to extend the life of such poles. These techniques, together with a full understanding of the modes of failure, make it possible to establish new strategies to further improve the environmental benefits of treated wooden poles.
D J Dickinson, B Calver