International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Drip irrigation provides a fairly even mode of moisture in the soil and, along with this, favorable air, heat, microbiology and nutrition. As a result, there is an increase in yields and an improvement in the quality of production.
In order to determine the impact of drip irrigation, on the size of the yield and the economic indicators, in the cultivation of raspberries in the soil and meteorological conditions of the area of the village of Chelopechene – Sofia researches of an everbearing variety “Lyulin” were carried out. Various options have been tested – from fully satisfying the daily needs of the culture by water, irrigation with 20% and 40% irrigation norms to non- irrigating conditions.
The results obtained in years with different security of meteorological factors show that the drip irrigation of raspberries has a positive effect on the economic indicators of its cultivation, the costs of creating the raspberry crop, the irrigation system and the cultivation of the crop are redeemed for two or three years.

The structure of production in agriculture is changing with the change of priorities, both at EU and national level. On the one hand, this is due to interconnection in individual sub-branches, on the other, to the replacement of traditional technologies with new ones. In both cases, this requires the maintenance of more equipment than is necessary for production and the corresponding increase in the cost of production and the reduction of the profit from production. Significant lagging of the machine-tractor fleet renewal processes and increased loading of the used equipment imply intensive physical wear and obsolescence.

Depending on the reasons for write-off, when determining the liquidation value of the machinery, account shall be taken of special features and the possibilities for further use of individual elements (parts, assemblies and aggregates). Several approaches are used to determine the liquidation value:

– the whole machine is considered scrap. The approach is applicable to working machines and attachments to self-propelled agricultural machinery;

– the whole machine is classified as scrap but is dismantled and divided according to the type of scrap (ferrous and non-ferrous metals). The approach is applicable to retractors and attachments to self-propelled agricultural machinery as well as stationary machinery for primary production processing;

– the machine is rated as scrap of ferrous and non-ferrous metals and second-hand spare parts. The approach is only applicable to physically worn machines.

In addition to that, an improved methodology for assessing the liquidation value of different groups of agricultural machinery for moral and physical extinction with and without residual resource elements is suggested.