Software support of production restructuring in quality management system of car service enterprise

The paper describes automation means of the quality management system’s functions for the purpose of optimization an autoservice enterprises (AE) activity. Activity of an enterprise can be explored at regional level, within the scope of an independent enterprise or structural unit and at the level of the certain select technological process. There is a relation between the levels. An important task is a modeling of enterprises activity at all levels. This research is performed at the enterprise PJSC “CHERKASSY-AUTO” in Cherkasy (Ukraine). This enterprise is included in “UkrAUTO” corporation. One of directions of an enterprise activity optimization is restructuring. For information support of the restructuring, a database model of the visual area in the UML notation has been created. The database consists of fourteen tables. The complex indicators of quality of services rendered at the enterprise are calculated. The location of the enterprise, quality estimation of completed services and their nomenclature were taken into account. The algorithms of selection optimal organization form of an enterprise are built for the subsystem of management quality system. The algorithms are implemented in visual development environment Delphi 7.0., supporting the concept of object-oriented programming. Technology of using a developed software package is described step by step. Saving of the results of the survey of AE customers is additionally provided. The modules of Delphi project contain the subprograms, in which are used the method AHP of Saaty and graph theory methods. The results of subsystem approbation indicate the efficiency of developed algorithms. The developed software complex gives an opportunity to get the forecast of the most frequently performed services, it can function both separately at the car service enterprises, and within the Intelligent Quality Management System (MIS) of AE.

Use of fiber-glass materials for protection of industrial pipes against corrosion

A method to increase the resistance to spread of crack-like and corrosion defects on the outer surface of pipelines by using a new, developed, multicomponent composite coating and a method for its application has been developed. The method is effective in terms of applying repair coating without taking the pipeline out of service. The protective coating, obtained according to this method to protect pipes from damage, is marked by heat resistance, strength, high adhesion to steel pipes, high insulating and anti-corrosion properties. The viscosity at impact of the coating obtained is 15 J, which corresponds to a very reinforced coating of class B. To reduce water absorption and increase adhesion, a polyurethane coating is applied to the pipe, which has water-repellent properties. This makes it possible to exclude from the process of strengthening the pipeline an additional finishing operation (applying a hydrophobic water-repellent coating to the surface of the pipe). After applying fiberglass to the epoxy coating layer, fiberglass coating is obtained, which, due to its high wetting ability and adhesion of epoxy resins to fiberglass, has high static and dynamic strength. Due to the low shrinkage of epoxy resins during their curing, microcracks are not formed on the surface of the coating. When fiberglass comes into contact with a heated polyurethane coating, an elastic layer is formed, which ensures reliable adhesion of the coating to the pipe; the transient specific electrical resistance of the coating is 1.1 ∙ Ohm/m2. Thus, the resulting coating is compatible with the cathodic protection system and ensures the resistance of the coating to peeling during cathodic polarization, as well as high resistance of the coating adhesion to steel in wet conditions. The coating is intended for both underwater use and for dry conditions, as well as for long-term operation wet conditions at temperatures up to 65º C. In relatively dry conditions, the coating operating temperature is up to plus 100º C. The coating is designed to protect and strengthen the surface of steel oil and gas pipelines at the stage of their manufacture, construction, transportation and repair. This coating can be used in other industries to protect pipelines and tanks from atmospheric, soil and other types of corrosion, as well as from mechanical damage.

Influence of reinforcing plastic surface deformation on surface performance of machine parts

The performance of the machines part reinforcement using surface plastic deformation shall be considered as formation of the whole complex of surface parameters and quality and their impact on the operational properties of these parts. The main surface quality parameters, affecting the performance of machine parts are geometric (microgeometry, wavelength, roughness, shape of inequalities, the size of the supporting surface, the direction of the traces of processing); physical parameters (structure, degree and slander depth, residual stresses in the surface layer). In the machine building, many methods of superficial plastic deformation are used for part reinforcement; these methods essentially differ in the scheme of impact of the surface deforming part to be treated. After analyzing the results obtained by scientists, involved in research on surface plastic deformation of surface layers and surfaces of parts, it was found that after hardening, practically all structural changes contribute to reinforcement of the surface layer material and increase the plastic deformation resistance. Increasing the density of dislocations and the separation of carbides, which block the shear slides and create obstacles to the movement of dislocations. Due to these changes, resistance to formation and spread of fatigue cracks have increased. The treatment depth, magnitude of residual stresses and increase in hardness depends on the original structure and chemical composition of the material. Reinforcement regimes have significant effects on the wear resistance. Use of diamond smoothing, vibration processing, combined methods (surface plastic deformation in combination with other reinforcement methods, as well as the use of a combined tool) opens up new possibilities for increasing the quality characteristics of the surface and the surface layer of parts, and accordingly, increasing their operational properties with all the diversity and complexity of used processes. Based on the results of the studies, practical recommendations on the application of methods of hardening by surface plastic deformation of machine parts and a methodology for designing technological processes for their manufacture considering manufacturing capabilities are proposed.

Single information space for innovation activity of industry-specific higher education institution

The work is aimed at development and improvement of the system of information provision and activation of innovation and project activity of universities for prepairing specialists of oil and gas industry. The authors have proposed a model of the information system based on the use of electronic document flow, implemented, at this stage, for the organization of the activity process. The workflow is based on the use of cloud-based Google services for schools with a backup repository on a local server. The availability of corporate e-mail and electronic signature is the condition of access. The preparation for the implementation of the network model of scientific development has been done. A specialized technical institution of higher education (HEI) has been chosen as an institutional basis for the functioning of the scientific and educational information space. An analysis of the existing business processes of the HEI’s work has been carried out using the approach of creating classifiers and time-based budgeting based on the map-tables. The conceptual model of the combination of initial work and scientific research has been developed. The use of Trello project management system for university teaching has been proposed because Trello is an extremely simple tool that is easy to implement in the workflow without long adaptation of the staff. This system supports the flexible management of the project team and integration with the services of working with documents. It has been established that in spite of the shortcomings, at the first stage of the project management implementation the use of such cloud service would allow to overcome the psychological inertia of participants in the process of work on projects without the heavy expenses. The proposed approaches to engineering education will allow using the potential of student youth for the development of innovations by scientific-educational project teams and minimize the costs of ensuring the functioning of a single information space of innovation-project activity in oil and gas industry.

Study of PDC drill bit crown shape for design optimization: angle of blade inclination aspect

The article studies PDC-type bit operation, in particular, the redistribution of loads on drill bit blades is simulated, depending on “cutter-rock” contact areas, which is determined by a drill bit design. This work aims at PDC bit design optimization, namely to study the effect of the blade angle to the horizontal axis on the torque generated by the bit. The study is based on the Voitanovich and Kuru’s model of Voitanovich and Kuru’s and has its core at determining the balance of forces acting on a single cutter. The scientific novelty of the work is that two areas of contact are considered for each cutter – the on the front and side surfaces. Also, it is hypothesized that the force of the reaction of the pore is directed towards the placement of heterogeneities of the rock. This approach makes it possible to consider the fluctuations of the bits due to the instability of the cutting forces, which in turn are caused by the instability of the properties of the fractured rocks (first of all, their structural heterogeneity).The spatial shape of the PDC cutter crown was studied, characterized primarily by the shape of its upper part, which in turn is characterized by the angle of inclination of the cutting part of the cutter. Contact areas for each cutter, the volume of the destroyed rock depending on the location of the cutter, as well as the loading for a single cutter, the torque for the whole blade and the bit were simulated in the work. The angles of inclination of the blade to the horizontal axis at which the minimum / maximum torques are observed are determined.Changing the inclination of the cutting part causes the redistribution of the destroyed rock volumes. This section dealt with worn-out chisels, and the load was distributed in proportion to the volume of the destroyed rock. It was found that increasing the angle of the blade causes an increase in the total torque for the bit. A method is proposed that allows optimization of the PDC bit design. An increase in the total twisting angle and the total deflection is observed for the cutters, which are most separated from the borehole face.

Design improvement of preventer shear rams

In case of an unexpected increase in the storm during drilling at sea or in other emergency cases, the drill or casing columns are cut off with cutters of pretensioners and sealed wells. The drill string remains in the well and it is kept by the pipe plugs of the pretensioners. Blind rams are fitted with a cutting blade, cutting pipes in the well, allowing blind rams to seal the well. The task was to improve the cross-cutting preventer rams to increase the efficiency of the drill pipe cutting. The proposed modernization of the cutter design makes it possible to cut the drill pipe completely. In her, as in the previous design, the cutting process is the same, but due to the shape of the cutting surfaces there is no pipe bending, but a complete cutting. However, the difference between these structures from foreign is that in the process of cutting the pipe first, its point deformation (puncture) occurs with a cutter. This, incontrast to other structures, reduces the load at the initial moment of the tube deformation on the hydraulic cylinders of the pre-filter, and therefore, the energy costs for this cutting process are reduced, and the load on other elements of the drive is reduced by the pre-plate layers.Key words: antiviral equipment, plate preventor, cut-off rams, pipe bending, finite-element analysis. To study the cutting process of a drill pipe, a three-dimensional model of the pipe itself and two dies were constructed. The three-dimensional model is created with simplified, since with the increase in the number of elements is complicated as the construction of a network of finite elements, and the calculation process itself continues for a very long time. The results obtained by the simulation model show the effectiveness of the cutting of the drill pipe and the possibility of complete closure of the pre-cutter with cross-sections.

Elements to improve theory of roller cutter bit with chisel teeth

The article deals with solving the problem of determination in the first approximation of the time of the interaction of tricone bit tooth with the rock and the maximum dynamic impact force. Considered the roller bit teeth are of types Sh and B. The shape of the bottom hole after the previous penetration the rock is adopted as having spherical mounds between paths. It is believed that deformations during the impact of the tooth occur only in the area of ​​the mounds, neglecting the masses of the rock material being deformed. The concept of the consolidated mass of the part of the rock, which is disintegrated and sections of the mass of the drill string with a roller bit is introduced. Separate consideration is given to determining the time and maximum impact force at the stages of sinking the rock and the raising of the tooth from it. In raising the plastic deformation of the material of the rock and its elastic return are taken into account. The determination of these parameters is carried out both without considering the moment of inertia of the roller bit, as well as taking into account this moment. It is shown that during the oblique impact of the tooth on the mound, taking into account the moment of inertia of the roller bit, it is necessary to know the coefficient of friction of the rocks over the tooth and the initial acceleration of the roller bit. In this case, the normal and the tangential component of the force of the specified impact of the tooth on the mound is considered separately. Were suggested analytical dependences for determination of the normal and tangent component of the shock interaction force module, as well as their maximum value.

Relationship between cathodic protection current and limit diffusion current as an additional criteria of cathodic protection

The influence of the temperature and oxygen concentration in NS4 solution on the electrochemical characteristics of X70 steel for pipelines and the relationship of cathodic protection current density to limiting diffusion current density, in the normalized DSTU 4219 range of protective polarization potentials from -0.75 V to -1.05 V (сh.s.е.) were investigated. It has been established that with increasing of the temperature from 20 to 80 °C, the corrosion activity of X70 steel increases, which is confirmed by more negative values of corrosion potential and an increasing of the corrosion rate, and indicates on the prevailing effect of temperature on the corrosion process compared to the effect of oxygen concentration. In the temperature range considered, the limiting diffusion current has a maximum value at 40 °C and decreases with increasing of temperature, correlating with a decreasing of the oxygen concentration. Under conditions of free oxygen access to the NS4 solution in the normalized DSTU 4219 range of protective polarization potentials, the ratio of cathodic protection to limiting diffusion current varies from 0.4 to 1.3 at temperatures (20-40) oС, at temperatures (60-80) oC the ratio is less than 1. Under conditions of limited oxygen access, the ratio increases from 1.1 to 4.7. Using calculated and experimental results, it was shown that, at various values of relationship , conditions for excessive hydrogen evolution can be created, which represents a threat to the safe operation of the pipeline over time. Data on the ratio values should be taken into account when analyzing the protection state of pipelines.

EXPRESS ESTIMATION OF THE ENERGY EFFICIENCY OF A CENTRIFUGAL PUMP WITHOUT EXPERIMENTAL DETERMINATION OF ITS EXPENSES

Using a mathematical model, created on the basis of the electrohydraulic analogy method, a methodology for express estimation of the energy efficiency of a centrifugal pump was developed. The design load angle for analyzing the efficiency of operating modes of hydraulic machines is determined. The dependence of the power-driven engine shaft and the total efficiency of the centrifugal pump on its calculated load angle is established. The relationship between load angle and speed coefficient, which is a prototype of an electromagnetic load angle which characterizes the synchronous machine operating mode, is determined. It is established the dependence of the main pump head on the calculated load angle and the differential pressure created by the centrifugal pump. The developed methodology makes it possible to avoid significant technical and financial difficulties, since flow meters have a high cost and certain requirements for installation, while manometers are established by the standard requirements of the technological process. The estimated value of the load angle of the centrifugal pump through its catalog parameters is determined. The operating characteristics for the main centrifugal pump of type НМ-7000-210 were calculated and built without experimental determination of its head. Such approach showed a good coincidence of calculated and experimental characteristics. Relative error of energy characteristics does not exceed ten percents. The proposed methodology can be used for express estimation of the efficiency of energy transformations of the whole electric drive pump unit. Express-analysis is a key to successful management of the energy economy through timely detection of inefficient modes of operation of electric-driven pump units and makes energy research cheaper.

MODELING OF IMPACT OF CENTRIFUGAL REINFORCEMENT MODES ON WEAR OF CUTTER TEETH OF DRILL BITS

A study was performed to improve the performance of drill bits. It is noted the main work item are cones, equipped with serrated arms, made in the form of solid or false teeth. It is noted reinforcement of cutters during destruction of rocks is subjected to intensive wear under the action of high loads at the bottom, significant temperature differences, in the presence of abrasive particles, changes in the rock hardness. To reduce the impact of these factors on the wear of rock-destruction weapons, comprehensive design and technological measures are proposed to create a rock-destructive tool and, in particular, its reinforcement. The efficiency criterion of such events is proposed to choose resistance of rock-cutting elements to various types of wear. For implementation of the proposed approach to creating effective reinforcement, a critical analysis of the design of the cutter teeth of drill bits equipped with teeth of various designs and technologies for their manufacture was performed, and rolling cutters with plug-in teeth made by centrifugal reinforcement were selected as the object of research as the most optimal. The design of such teeth, implemented by a centrifugal casting process, provides for location of the rock-breaking hard alloy in the tooth head. The tooth root, pressed into the cutter housing, is made of steel. A mathematical model of the process of centrifugal reinforcement of cutter teeth of drill bits was developed to study the impact of process conditions on their resistance to impact-abrasive wear. As independent variables, otherwise the factors determining the technological process modes of centrifugal reinforcement were selected X1, X2, X3, X4, their main level and intervals of variation, the upper and lower levels were established. A full factor experiment 24 was used in the research. An experimental plan was drawn up. In accordance with the chosen plan, 16 active experiments were performed; each experiment was repeated three times. Then, a mathematical model and its describing regression equation were developed. The impact degree of process factors on the value of shock-abrasive wear of teeth and their optimum values were determined.