Use of emission indicators related to CO2 emissions in the ecological assessment of an agricultural tractor

The paper presents the proposed proprietary M exhaust emission indicator, which is based on the assumption that CO2 emissions are a measure of the correctness of the combustion process. The measurements were performed using a farm tractor meeting the Tier 3 emission norm, operated in real conditions during plowing work. The tests were carried out for a given land section at three speeds In the analysis of test results, the net engine work was used, as it is carried out in the type approval procedures. When measuring in real operating conditions, the torque read from the OBD system is overstated because it takes into account the engine’s internal resistance. In the analysis of test results, the fuel consumption, emission indicators of gaseous compounds and particulates were determined, and the best conditions for conducting agricultural works were indicated in terms of their impact on the natural environment. The aim of the work is to verify the possibility of determining the emission index for an off-road vehicle and a comparative analysis of its values for various operating parameters of a farm tractor. On this basis, it was found that the lowest values of the M identity were recorded for the test characterized by a vehicle speed of 15 km/h.

Estimation of Productivity and Costs of Using a Track Mini-Harvester with a Stroke Head for the First Commercial Thinning of a Scots Pine Stand

The aim of the present work was to estimate the productivity and costs of timber harvesting and forwarding during the first commercial thinning of a Scots pine stand. Three harvesting models were introduced and compared: narrow trail, wide access trail, and schematic extraction. The analyzed harvesting equipment consisted of a track mini-excavator (34 kW) with a stroke harvester head (gripping range 4–30 cm), and a farm tractor coupled to a logging trailer with a hydraulic crane. Merchantable timber (roundwood with a minimum diameter of 5 cm inside bark) was harvested from a 25-year-old planted Scots pine stand growing on a grid of 1.4 m × 1.8 m. The study showed the productivity of the mini-harvester ranged from 3.09 to 3.47 m3/PMH15 (productive machine hours plus 15 min), and that of the forwarding equipment to be 4.07 m3/PMH15. The analyzed model of productivity as a function of tree volume and thinning intensity was statistically significant, but the intensity parameter was significant only on plots located along wide access trails (3.7 m) and insignificant on plots located along narrow access trails (2.5 m). The distance between trees was not found to be significant. The calculated net machine costs for the forwarding equipment and track mini-harvester were EUR 36.12 and 52.47 per PMH, respectively. An increase in the usage rate of the harvesting equipment to 80% would reduce the harvesting and forwarding costs to EUR 22.07/m3.

Productivity and Cost Models for the First Commercial Thinning of a Scots Pine Stand Using an Excavator with an Arbro 400S Harvester Head and a Farm Tractor Coupled to a Logging Trailer

The objective of the present work was to determine the productivity and costs of timber harvesting and skidding during the first commercial thinning of a Scots pine stand. The analyzed harvesting set consisted of a mini-excavator (34 kW) with an stroke harvester head (gripping range: 4–30 cm), and a farm tractor coupled to an logging trailer with a hydraulic crane. Merchantable timber (roundwood with a minimum diameter of 5 cm inside bark) was harvested from a 25-year old planted Scots pine stand growing on a grid of 1.4×1.8 m. The study showed the productivity of the mini-harvester range from 3.09 to 3.47 m3∙PMH15 -1, and that of the forwarding set to be 4.07 m3∙PMH15 -1. The analyzed model of productivity as a function of individual tree volume and thinning intensity was statistically significant, but the intensity parameter was significant only on plots located along wide access trails (3.7 m) and insignificant on plots located along the narrow access trial (2.5m). The intertree distance was not found to be significant. The calculated net machine costs for the forwarding set and mini-harvester were 36.12 Euro∙PMH 1 and 52.47 Euro∙PMH-1, respectively. An increase in the utilization rate of the harvesting set to 80% would reduce the timber harvesting and skidding costs to 22.07 Euro∙m-3.

POWER SUPPLY OF FARM TRACTOR INDUSTRY IN RUSSIA

Determining the prospects for the development of the tractor fl eet in Russia and its supplying with power units is an important task in establishing a technological foundation to eff ectively tackle the problems of agricultural production. Taking into consideration the indicator of power supply in agriculture in the world’s economically developed countries, the authors consider the domestic needs in agricultural tractors and engines. As a result of the analysis, it is shown that the fl eet of agricultural tractors is at a low level of about 200 thousand units, and it requires further serious development. To ensure eff ective agricultural production, it is necessary to balance the level of farm tractor availability in Russia with that of economically advanced countries. The indicator of 4 kW/ha was taken as a promising level of tractor availability, and the required number of tractors was determined. The analysis was carried out for the cultivation of arable land in Russia with an area of 80 million hectares as of 2020 and amounted to about 2.5 million units for the entire range of agricultural tractors taking into account their traction class. To cultivate all arable areas in Russia, which amounted to about 120 million hectares in 1990, a third more equipment will be required. To maintain the tractor fl eet at this level, it is necessary to ensure an annual supply of at least 250 thousand units of various engines with a total capacity of at least 320 GW. This problem can be solved through increasing the production capacity of existing engine-building plants and designing new diesel engines for tractors of traction classes 0.6…1.4 with a capacity between 20 and 70 kW.

Rare pathology in a trauma patient: air embolism following peripheral intravenous access

A 62-year-old man presented as a trauma alert after a farm tractor accident. He was managed according to ATLS protocol. During initial trauma resuscitation, he developed an iatrogenic air embolus. The patient was treated conservatively by positioning him head down and tilted to the left (Durant’s manoeuvre). Repeat CT scan performed 4 hours later showed resolution of the air embolus. He had no sequelae.

POWER SUPPLY OF FARM TRACTOR INDUSTRY IN RUSSIA

Determining the prospects for the development of the tractor fl eet in Russia and its supplying with power units is an important task in establishing a technological foundation to eff ectively tackle the problems of agricultural production. Taking into consideration the indicator of power supply in agriculture in the world’s economically developed countries, the authors consider the domestic needs in agricultural tractors and engines. As a result of the analysis, it is shown that the fl eet of agricultural tractors is at a low level of about 200 thousand units, and it requires further serious development. To ensure eff ective agricultural production, it is necessary to balance the level of farm tractor availability in Russia with that of economically advanced countries. The indicator of 4 kW/ha was taken as a promising level of tractor availability, and the required number of tractors was determined. The analysis was carried out for the cultivation of arable land in Russia with an area of 80 million hectares as of 2020 and amounted to about 2.5 million units for the entire range of agricultural tractors taking into account their traction class. To cultivate all arable areas in Russia, which amounted to about 120 million hectares in 1990, a third more equipment will be required. To maintain the tractor fl eet at this level, it is necessary to ensure an annual supply of at least 250 thousand units of various engines with a total capacity of at least 320 GW. This problem can be solved through increasing the production capacity of existing engine-building plants and designing new diesel engines for tractors of traction classes 0.6…1.4 with a capacity between 20 and 70 kW.