Articles containing the keyword 'timber transportation'

Light and economic FM-CW radar has been developed for controlling the bearing capacity of ice roads and landings on ice used for timber transportation and storage of timber in Finland. It was tested on natural ice and ice roads of three lakes in Southern Finland and one location on sea on the southren coast of Finland (a total of 166 observations). Ice thickness varied from 0 to 100 cm. Correlation coefficient between auger and radar measured ice thickness was r=0.99 and absolute error varied from -10 to +7 cm. The quality of ice had no influence, but by improving the interpretation of results, also the quality factors might be detected.

The PDF includes a summary in Finnish.

• Saarilahti, E-mail: ms@mm.unknown

Measurement of timber in a vehicle load or in a bundle is best performed at the mill where the measuring of large quantities can be mechanized and sampling is possible. Load measurement methods include calculation of the number of units, measurement of pile volume, weight scaling and determination of solid content in accordance with Archimedes principle by immersion in water. For some timber assortments, load measurement is sufficiently accurate and suitable unit of measure. The accuracy of load measurement can be increased or the result can be converted by sampling to a more appropriate unit of measure.

In load sampling measurement, a sample is taken from the population, and the desired more accurate measurement is made from the sample. The basic measurement for the whole population can be converted into the more accurate measuring unit by means of the ratio between it and the basic measure. Unit, pile and weight sampling can be used. The aim for pulpwood is to calculate the dry matter content without bark, which means that the amount of bark and the dry weight of wood must be determined by sampling.

The size of the sample depends on size of the population, variation of the ratio between the loads, and the accuracy required. As the quantity of wood to be measured decreases, sampling measurement will reduce the measuring costs by up to 80%. In addition, there is saving in costs by rationalization.

The PDF includes a summary in English.

• Leinonen, E-mail: el@mm.unknown
• Rikkonen, E-mail: pr@mm.unknown

Seasonal variation in the sawmill industry of Finland was studied in an investigation based on questionnaires answered by a random sample of sawmills concerning the time period of 1958-1960. The method is described in detail in a separate article in Acta Forestalia Fennica issue 75 no. 1.

The seasonal variations in purchase of roundwood was largest in big sawmills, which purchase the main part of the timber as standing sales and buy most of the wood from the State Forest auctions at the end of September. Also, they can afford to reserve their material earlier than the smaller companies. The saw logs are mainly felled in the winter in Finland because the climatic conditions and availability of labour are best at that time. Small sawmills begin fellings a little earlier than the larger ones.

In long-transport of timber the proportion of floating decreased from 47% in 1958 to 38% in 1960. At the same time, proportion of truck transport increased from 48% to 55%. Small sawmills use almost exclusively land transport. They received almost three-fourths of their logs between January and May, because the sawing is concentrated in the first half of the year. Therefore, floating does not suit for their transport method. The larger the sawmill, the later is the seasonal peak of log deliveries. The output of the big sawmills is distributed more evenly thoughout the year. The smaller the sawmill, the quicker is the turnover of raw material and the smaller the sawlog inventories.

The seasonal variation in output is sharper at small sawmills where sawing is concentrated in the first half of the year. The seasonal peak of the early spring is due to the aim at getting the sawn wood to dry early enough for shipments in the summer. Air drying takes an average of 4 ½ months. Kiln drying is more common at the larger sawmills, and gives them more flexibility. Due to the large seasonal variation in operation, the capacity of the small mills is poorly utilized. Domestic sales of sawn wood levels up the seasonality of the deliveries. Export sales are concentrated at the end and turn of the year. Also, the seasonal peak of expenditure occurs in the winter, but that of income in the summer.

The PDF includes a summary in English.

• Ervasti, E-mail: se@mm.unknown

Central Association of Finnish Forest Industries decided in 1953 to begin collecting annual statistics of timber transportation of its members. The survey of members covers almost 97% of the timber transportations of the member companies, which have production over 1,000 cu ft. In all 79 companies answered the survey. Their total timber transportation was 166,4 million cu ft in 1952.

The long-distance transportation of saw logs by horse transport directly to the mill or other such location was 1,297 cu ft, by truck transport 42,644 cu ft, by rail transport 6,707 cu ft, and by water transport 115,789 cu ft. The average transportation distance was for horse transport 2.4 km, truck transport 27 km, rail transport 224 km and water transport 209 km.

The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.
The PDF includes a summary in German.

• Lindfors, E-mail: jl@mm.unknown

The costs of floating have increased by about 20-fold after the Second World War in Finland, which has raised concerns in the forest sector. At the same time, the costs of road transport have increased by 16% and costs of rail transport by 15%. Floating has been replaced mainly by road transport in transport of roundwood, especially near the factories. This development is likely to continue as new roads are built and the truck fleet develops.  

In spite of the changes in timber transportation, floating was still the most common way of transporting roundwood in 1952: 69% of saw logs, 53% of veneer timber, 42% of domestic pulp wood, 14% of exported pulp wood and mining timber and 14% of firewood was transported by a water route. There are several ways to improve the efficiency of floating and decrease its costs. This can be achieved in two ways. First, using modern technology, such as tugboats, bundlers and other equipment, and second, improving the operation and co-operation between different actors.  

The PDF includes a summary in German. 

• Stolpe, E-mail: ns@mm.unknown

About 17.5% of forest lands of Finland is situated around the river and lake system of Lake Saimaa. Furthermore, the growth of the forests  of the area correspond about 25% of the total growth of forests in Finland. The watersystem is one of the most important portages of roundwood in the country. It consists 11,000 km of floating channels, 2,000 km of which suit for floating in bundles. Annually 30-35 million cu ft of saw logs, 7 million cu ft of veneer timber and 2,5-3 million cu ft of pulp wood is floated in the area.

Even if the water system at present still suits well for floating, there are many opportunities for development, which would improve its competitiveness against other modes of transport. Several different sites where building of floating channels or improving the floatways are needed are described in the article.

The PDF includes a summary in German.

• Roitto, E-mail: wr@mm.unknown

 The numerous waterways have promoted the development of forest industry in Finland by offering an easy way to transport timber almost in the whole country. Floating associations arrange the floating for its members. This study, accomplished in the Forest Research Institute, compiles the statistics of the different associations in 1922­‒1927.  The volume of timber transported by the floating associations increased by 40% during the 6-year period, reaching 10.5 million m³ in 1927. The increase has been supported by the number of collectively used floating channels. The number of the floating associations increase from 17 to 26 and the length of the floating channels used by them to 8,300 km in 1922‒1927. About 70‒80% of the transported timber was logs and the 20‒30% small timber. Floated timber comprised 70-80% of the all roundwood used in the forest industry in Finland at the time. Majority of the logs were softwood.

The PDF includes a summary in German.

• Sierla, E-mail: vs@mm.unknown

The transport unit in roundwood towing on Lake Iso-Saimaa in Central Finland comprises a tug and a raft of bundled wood with a towline between them. There are several factors influencing the economic size of the transport unit in roundwood towing. These are changing with the enterprises and along with general developments. In this paper these factors or factor groups are seen from the point of view of the enterprise. The main question is to determine the most economic combination of tug and raft size.

From the point of view of the towing enterprises the unit costs of transport are the most decisive factor. Both the size of the raft as well as the power of the tug influence strongly the unit costs. As a long-term goal a raft of about 35,000 m³ and a tug of 550 kW or more is considered to be advisable. The width of channels and sounds then allow a free passage for rafts being 36–40 m wide.

The PDF includes a summary in Finnish and in French.

• Roitto, E-mail: yr@mm.unknown

The first part of the study includes a summary of conclusions from five earlier reports dealing with terrain transportation costs, effect of terrain, load, snow and additional machine components on the mobility of forest tractors, and the distance a vehicle has to move in forest transportation of timber. In the second part of the study the effect of these separate factors on the transport output have been analysed on the basis of simulating a transportation of 3,000 loads by computer.

It was concluded that no specific terrain factor had a dominating effect on any component of the forwarding output. However, many terrain-factor combinations with a nonsignificant effect on the mobility and also on the forwarding output were identified. The most significant factors affecting the output were the size of load and the distance driven during the cycle.

The PDF includes a summary in Finnish.

• Haarlaa, E-mail: rh@mm.unknown

Our research aimed to quantify and evaluate the stress loading of drivers by monitoring the loading of the radial extensor muscle at the wrist joint (musculus extensor carpi radialis) when they drove different types of timber trucks. We monitored changes in the electric potential of skeletal muscles with electromyographic measurements and measurements of changes of heart rate using the Biofeedback 2000 ^x-pert device. The drivers were observed throughout their work shifts during normal operation of logging trucks and logging trucks with trailers. As a reference, muscle load was measured when driving a passenger car. We evaluated the normality of the measured data and obtained descriptive statistics from the individual measurements. The differences in stress load associated with driving the different types of vehicles increased whilst driving on lower-class roads. Results showed a high stress load for drivers of loaded vehicles when driving on narrow roads. It was more challenging to control a loaded logging truck with a trailer than driving a logging truck, with the difference in muscular loading reaching 22.5%. Driving a logging truck with a trailer produced 46.5% more muscle loading compared to driving a loaded passenger car. For preventive health and safety reasons, it would be reasonable to alternate between drivers when operating various vehicles, thus minimizing the development of possible health issues.

• Škvor, Department of Forestry Technologies and Construction, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Prague 6 - Suchdol, Czech Republic https://orcid.org/0000-0001-7540-4761 E-mail: skvorp@fld.czu.cz
• Jankovský, Department of Forestry Technologies and Construction, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Prague 6 - Suchdol, Czech Republic E-mail: jankovskym@fld.czu.cz
• Natov, Department of Forestry Technologies and Construction, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Prague 6 - Suchdol, Czech Republic E-mail: natov@fld.czu.cz
• Dvořák, Department of Forestry Technologies and Construction, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Prague 6 - Suchdol, Czech Republic https://orcid.org/0000-0002-5986-8002 E-mail: dvorakj@fld.czu.cz