Volodin S. Scientific substantiation of improvement of shut-off and regulating devices of the equipment of sugar production

The dissertation is devoted to the complex research of locking and regulating devices with electric pneumatic drive of tracking type and search of rational design and operational parameters of locking and regulating elements as a part of technological equipment of sugar production. New experimental stands have been created on which the operation of shut-off and control devices in the two-circuit network has been studied: the high-pressure zone is compressed by the wind, and the low-pressure zone is water. Mathematical modeling of the influence of water on the operation of the elements of shut-off and control valves, which allows to obtain systems of equations to describe the operation of structurally similar elements. The problems of analysis and synthesis of dynamic parameters of the automatic control system are solved. The adequacy of the created models is confirmed by the results of the conducted experimental researches. Experimentally determined and proposed modes of operation of shut-off and control devices in the technological process of sugar production. The characteristics of actuators are investigated: throughput, short-circuit density with its step-by-step change by the regulating body at pressure difference on the drive in 0,1MPa; the current value of throughput at the set size of a course of a working link in percent is calculated. The method of research of locking–regulating elements on the basis of the synthesized mathematical model, experimental-analytical researches and with use of methods of identification is offered. The operational properties of actuators are substantiated (control valves) largely determine the main characteristics: hydraulic, power and design for the drive as a whole. The throughput characteristic which should be chosen so that in operational conditions the necessary expense characteristic was created is investigated. The use of the SL series positioner actuator makes it possible to control the flow characteristic taking into account the stroke and pressure in the pneumatic system. The estimation of parameters of work of the shut-off and regulating system of the technological equipment in an operative mode is formed. Then the found parameters of the model of the object W are used to design the controller according to the criterion of optimality. In the course of research, control systems for the elements shut-off and control valves were developed, in particular, the D376XE75 disc interflange valve with the ERDNAF-N52N tracking drive (4-20mA control signal). Empirical methods have been used to calculate the cost characteristics for evaluating the operation of control valves and shutoff elements. Based on the obtained research results and practical implementation, the rational characteristics of shut-off and control devices with position actuators to ensure the specified technological regulations of the equipment are determined. Typical designs of shutoff and control devices as a part of technological pipelines of sugar production are improved. The recommendations of the industry concerning a technique of check of their efficiency of work are given. It is recommended to use ball valves with a V-neck and electropneumatic position actuator for dosing the flow of water entering the reduction-cooling unit in order to cool and humidify the steam. To maintain the level in the evaporator station housings, it is recommended to install on the pipeline between adjacent housings interflange disk valves of the DN type with positional electropneumatic drive. The practical implementation of the proposed elements has increased the efficiency of the process of evaporation of juice by increasing the stability of maintaining levels, which allows you to more accurately maintain the residence time of the juice in the shells. New control modules as a part of shut-off and regulating systems which allow to change the basic technological parameters of process adhering to technological regulations without essential energy losses are offered. The presented developments have been tested in the sugar industry, the results of physical and mathematical modeling are fully confirmed by experimental data. New developments have been tested at the enterprises of the sugar industry of Ukraine and introduced into production.