Table of Contents

  • ИЗСЛЕДВАНЕ НА ПРОЦЕСА НА РАЗДЕЛЯНЕ НА ЗЪРНЕНИ СМЕСИ ПО ПОВЪРХНОСТТА НА МЕХАНИЧНИ СЕПАРАТОРИ – II ЧАСТ

    pg(s) 12-14

    Ситата, като механични сепаратори са основно средство за разделяне по размери на зърнени смеси, които подлежат на почистване или сортиране. Обикновено се използват сита с плоска работна повърхнина и колебателно движение.
    Независимо от конструкцията им обаче процеса на разделяне има вероятностен характер и по дължина на сепариращите органи се описва най-точно с експоненциална зависимост.
    Сепариращата способност, респ. качеството на работа на механичните сепаратори се характеризират съответно от коефициента на сепарация (µ(x)) и пълнотата (ефекта) на разделяне (ε). Всяка от тези характеристики зависи от множество фактори, но е установено, че най-силно се влияят от дължината на сепариращия орган. По своята същност коефициентът изразява вероятността за пресяване на една отделна зърнена частица през участък с дължина единица. Промяната в коефициента на сепарация при сепаратори с равни работни площи не е задължително да води до промяна в качеството им на работа. Това може да се обясни с факта, че при равни други условия на работа промяната на дължината не променя площта им, а това означава постоянно специфичното натоварване и съответно еднакъв ефект на разделяне. От тази гледна точка следва коефициента на сепарация и ефекта на разделяне да бъдат обосновавани на база на конструктивните параметри на сепаратора, от които зависи неговата работна площ.

  • TECHNOLOGY AND COMPLECS MACHINES FOR FLOWER BULBS PRODUCTION

    pg(s) 15-21

    Production of bulbs from flower crops is one of the most dynamic sectors in specific farming systems. Due to their intensive nature, a rapid change in growing conditions, as they tend to change more quickly than other traditional Bulgarian agricultural crops. To implement specialized farming systems the following important conditions must be available: – the availability of highly specialized staff, familiar with specific biological and physiological characteristics of flower crops, with growing technologies, harvesting, storagе and accelerated production of flowers; – the existence of universal and specialized machines and equipment; – аn environment оф propagation and storage, incl. laboratory facilities and outdoor production areas.

  • ТЕОРЕТИЧЕН АНАЛИЗ И ОБОСНОВАВАНЕ НА ВЪЗМОЖНОСТТА ЗА ДИАГНОСТИРАНЕ НА ДИЗЕЛОВИ ДВИГАТЕЛИ ПО НЕРАВНОМЕРНОСТТА НА ВЪРТЕНЕ НА КОЛЯНОВИЯ ВАЛ ЗА ЦИКЪЛ

    pg(s) 25-26

    In this paper a theoretical studies of instantaneous angular speed and torque fluctuation of diesel engine crankshaft have been conducted. It was evaluated the possibility to diagnose combustion related faults under stationary state.

  • CHARACTERISTICS CROP PLANTS IN THE ASPECT OF THE PROCESS OF SPRAYING

    pg(s) 29-33

    Pesticides used in agriculture during chemical plant protection against pests pose a significant threat to the environment. Pesticide should be characterized by: high toxicity in relation to pests and low toxicity compared to other organisms, adequate durability and high susceptibility to degradation. In practice, the achievement of these goals is often impossible. The aim of the study was, therefore, to use a parametric characterization of sprayed plant in the aspect of the process of spraying. In order to do this study the degree of coverage of sprayed objects using selected nozzles assessing which of the tested nozzles has the best properties in terms of covering horizontal and vertical surfaces sprayed plants. In the second part of the study was performed parametric characteristics selected for plant research at the surfaces of vertical and horizontal projections and ratio settings sprayed surface.

  • DURABILITY DETERMINATION OF DEPOSITED LAYERS OF IRON PARTS OF AGRICULTURE AND TRANSPORTING MACHINERY EQUIPMENT THROUGH VIBRATING ARC OVERLAYING PROCESS

    pg(s) 3-5

    The dynamics of wear index as well as wear resistance changing is established within experimental research of deposited lay- ers upon steel and iron parts. The summary wear index at the end of experimental research of iron parts is about 4 times bigger than the wear index established within steel parts experimental research. The relative wear resistance of deposited layers upon steel parts through vibrating gas metal arc overlaying process is about 10 times higher than layers deposited on iron parts within the same working conditions.

  • The quality of procedure spraying on crops flat in the aspect of the characteristics of sprayed plants

    pg(s) 34-38

    The use of plant protection products are the most effective method to protect crops from pests. The primary goal of procedure is to spray as effective as possible to control pests. The effectiveness of this, like the level of pesticide use and safety during procedure depends largely on the quality of the liquid spray atomization. One of the three determinants of the quality of the procedure spray is the degree of coverage of sprayed objects. However, both the coverage and the other two – applying the liquid spray and the uniformity distribution of liquid. None of these indicators do not take into account the characteristics of the plant spray. Therefore, the UP Institute of Agricultural Engineering in Wroclaw was conducted a two-phase study, whose aim was to show the degree of coverage of sprayed objects in the aspect of the characteristics of sprayed plants in the flat field crops.

  • ABOUT THE METHODOLOGICAL BASES OF THE PROBLEM FOR AN IMPROVEMENT OF AN EXISTING SOLUTION

    pg(s) 6-8

    The engineering task – to improve the existing solution starts when, during the cycles of manufacturing or intended use of a technical system, it appeared preconditions for achieving better results. Although the problem is common for the engineering practice, there is no generally accepted model (algorithm) for its solution. For the harvesting of soy crops and other row crops in the country headers HPS are widely used, which are manufactured at METAREM – AD Pavlikeni. For the past more than thirty years since the start of mass production, headers passed their long path of development and improvement. Through the analysis of the collaboration of TISEM – AD, Ruse and METAREM – AD in the improvement of headers HPS, the types of activities and the content of the work are clarified. On this basis, is proposed a model (algorithm) to solve the engineering task to improve the existing solution, which covers all the activities of the design process.

  • CHEMICAL AND MICROBIOLOGICAL CONTAMINATION OF DIESEL FUEL USED IN FARMING TECHNIQUES

    pg(s) 9-11

    Diesel fuels are unstable on storage. Instability is caused by chemical and microbiological processes. The chemical processes related to the formation of asphaltenes. Microbiological processes associated with the formation of molds, fungi, bacteria. They all cause damage to the engine, in particular in the food system. The article shows the check you of diesel fuels used agricultural machinery for the presence of chemical and microbiological contaminants.