Hydraulic Equipment Research Articles

Development of Expanded Steel Pipe Pile to Enhance Bearing Capacity

An expanded steel pipe pile increases the cross-sectional area of conventional micropile by expanding the steel pipe to exhibit a higher bearing capacity owing to increased frictional resistance. However, construction cases of the expanded steel pipe pile are insufficient due to the absence of equipment for expanding steel pipes inside the ground. In this study, hydraulic expansion equipment was developed to verify the reinforcing impact on the bearing capacity and field applicability of the expanded steel pipe pile. A series of laboratory and test bed experiments was conducted to measure the expansion time and deformation of carbon steel pipes by using the developed equipment. The results of these experiments demonstrated that the developed equipment has sufficient ability and constructability to be used in the field for constructing expanded steel pipe piles. Then, field load tests were performed by constructing expanded and conventional steel pipe piles to confirm the improved bearing capacity of the expanded steel pipe pile compared to that of the conventional micropile. As a result, the expanded steel pipe pile exhibited a 20.88% increase in bearing capacity compared to that of the conventional steel pipe pile.

СОВЕРШЕНСТВОВАНИЕ КОНСТРУКЦИИ ГИДРОЦИЛИНДРОВ, ИСПОЛЬЗУЕМЫХ В ГИДРООБОРУДОВАНИИ ЗЕМЛЕРОЙНОЙ ТЕХНИКИ

The article discusses the issues of improving the design of hydraulic cylinders used in hydraulic equipment of earthmoving equipment (for example, bulldozers), gives practical recommendations for their modernization, and also presents the results of calculating the basic geometric and power parameters of the improved design (Patent for invention RU 2702205). The upgraded hydraulic cylinder consists of a housing, a piston with a rod and an O-ring made of elastic material located in the groove of the lid. A distinctive feature from known analogues is that in the cover of the hy-draulic cylinder housing made of diamagnetic material, coaxially to the piston rod, a magnetic ring is installed, contacting through an air gap with another magnetic pole of the same name of another split ring of a smaller diameter than the first. On the inner forming surface of the magnet-ic ring there are projections and depressions of rectangular cross-section, in which there are corre-sponding-sized projections and depressions of the ring made of elastic material, and the inner sur-face of the latter has a cylindrical shape and interacts with the reciprocal surface of the piston rod. The calculation of the forces generated by the magnetic fields of permanent magnets used in the sealing devices of hydraulic cylinder rods was carried out according to the original method. The results of the study are recommended to both domestic and foreign research institutes, design and production structures of agricultural engineering for further study, refinement and possible im-plementation into practice. The proposed directions for the modernization of sealing devices of hydraulic cylinder rods can be used to improve the operational reliability of hydraulic equipment not only for earthmoving equipment, but also for other agricultural machines (for example, recla-mation).

Intensification of Restoration of Hydraulic Equipment Components by Iron Plating in the Flow of Electrolyte

The influence of electrolysis conditions and the composition of electrolyte for iron plating in the flow of electrolyte on the adhesion strength, microhardness and wear resistance of coatings were studied. The optimal composition of electrolyte for iron plating and the structure of coatings that provide the highest abrasive wear resistance were determined. Advisability of using iron plating in the flow of electrolyte for restoration of spools for hydraulic control valves was demonstrated.

Universal test bench for studying automatic systems to control operating modes of hydraulic drilling machines and hydraulic equipment

The paper presents hydraulic diagrams of the developed universal test bench for the practical study of designed automation tools, obtaining their output parameters, as well as for adjusting hydraulic liquid flow controllers and analyzing the operability of automatic systems for regulating the operating modes of drilling machines. The operating principle of test bench and technical characteristics of its main hydraulic devices are investigated.

МОДЕЛИРОВАНИЕ РАБОЧИХ ПРОЦЕССОВ ЭНЕРГОСБЕРЕГАЮЩЕГО ГИДРОПРИВОДА МЕХАНИЗМА ПОДЪЕМА ЛЕСНОГО МАНИПУЛЯТОРА

At present Russia has adopted a course towards the creation of competitive machinery and equipment. This also applies to mobile manipulator-type forestry machines. Therefore, the design and creation of forestry manipulators with an energy-saving hydraulic drive is an urgent task. The analysis of research of technological, dynamic and kinematic characteristics of manipulator-type machines is given. A new hydrokinematic diagram of the boom lifting mechanism with an energy recuperation system in starting and braking modes is presented. A mathematical model of the boom lifting process has been developed, described by a system of nonlinear differential equations of the second order. Due to nonlinearity, it is impossible to solve the problem in an explicit form; therefore, the finite difference method is used, in which all derivatives are replaced by the corresponding difference analogs. Thus, the original system is reduced to a system of second-order recurrence relations. To solve the relations, the methods of operator theory and functional analysis are used. The sought-for functions are found in the form of a set of points at the nodes of the division of the segment in time. Preliminary calculations using the MathCad program showed that the connection of an energy-saving damping device to the hydraulic drive of the boom lifting mechanism makes it possible to reduce the peak pressure in the hydraulic line of the piston cavity of the hydraulic cylinder during transient modes by 1.5-1.6 times. Bench hydraulic manipulator, made it possible to obtain statistical data on the analysis of the pressure of the system without and with an accumulator, as well as the amount of stored energy per cycle, which amounted to about 30%. The mathematical model of the presented energy-saving hydraulic drive of the forest hydraulic manipulator shows the fundamental possibility of implementing the principle of energy saving during starting and braking modes of loading and unloading operations. Reducing the dynamic loading and energy intensity of the working processes of the boom lifting mechanism of the forestry manipulator by justifying the parameters of the energy-saving damping device of the hydraulic drive allows increasing the reliability of the manipulator, reducing energy costs, as well as the downtime for repairs due to the failure of hydraulic equipment. The results obtained can be used in the design of recuperative systems for other lifting equipment in construction and agriculture

Graded Preparation and Industrial Applications of Large-Ball Polyolefin Catalyst Carriers

In the process of preparing polyolefin catalyst carrier, the particle size is often unqualified because of the adhesion of smaller particles to each other and the crushing effect of mechanical vibration. To improve the output of target products, reduce loss, and improve yield, a high-precision and high-efficiency carrier particle classification process was developed according to the embedded principle. The hydraulic hydrocyclone equipment designed in this work could eliminate short-circuit flow and achieve good integration of the internal flow field, thereby enhancing the separation accuracy and high separation efficiency. The process was successfully applied to the industry with smooth operation. The large-ball polyolefin catalyst carrier prepared by grading showed a small distribution coefficient, high yield, and excellent polymerization performance, and the average particle size of the graded large ball catalyst support was 65–75 μm with the SPAN < 0.7, which could meet the needs of DQC700 series catalyst products.

Constructive-Functional Analysis and Sizing of Hydraulic Filters

The reliability of hydrostatic installations depends on the low level of impurities in an environment with pressure at an allowable value, which avoids an accentuated wear of the individual elements of the installations. Hydraulic filters are elements that have a role in protecting the hydrostatic installations from the particles that are found in the hydraulic oil. The paper aims to present some of the elements underlying the construction of hydraulic environment filtration equipment, certain conditions that are imposed on them, as well as the main problems related to the calculation and sizing of filters.

Selection of Nanostructured Zirconium Dioxide Crystals under Dry Friction against Molybdenum

The article considers the issues of contact interaction of nanostructured zirconium dioxide crystals with molybdenum coating on titanium-based alloy ВТ9. The following statement is substantiated: the best mechanical properties of crystals correspond to the total amount of 2.8% additives of stabilizing and doping rare earths elements. Antifriction properties of crystals under dry friction against molybdenum are investigated. Tribological testing was performed on a reciprocating friction gauge simulating the operation of a plunger in a cylinder. The high scoring resistance of the friction couple under study was experimentally proved; the friction coefficient did not exceed 0.07. On the basis of the study performed, the friction couple is defined as promising for increasing the lifetime and reliability of friction units for hydraulic equipment and fuel pumps.

Multiparameter measuring system using fiber optic sensors for hydraulic temperature, pressure and flow monitoring

In this paper, based on the research of fiber optic sensing technology, a multiparameter measuring system for hydraulic parameter monitoring is developed and evaluated. The sensing theory, design, calibration, and installation of the proposed metal-coated fiber Bragg grating temperature sensor, fiber Bragg grating flow sensor, and Fabry-Perot pressure sensor are detailed in the paper. A special hydraulic platform is designed for system test and the parameter monitoring condition of the hydraulic platform is displayed by the graphical user interface designed by using LabVIEW. The effectiveness of the designed system is verified by analyzing and comparing the obtained data of electrical sensors and the proposed sensors installed in the hydraulic platform. Experimental results indicate that the designed system using fiber optic sensing technology can accurately detect the parameters of the hydraulic equipment, and can be potentially used for real-time detection for condition monitoring of hydraulic equipment by analyzing the characteristic parameters.

Research on wear characteristics of spraying material layer on hydraulic equipment of multi-axis CNC machine tool based on discrete element method

In order to solve the problems of low accuracy and long time-consuming of traditional methods in analysing the wear characteristics of spraying material layer of multi-axis CNC machine tool hydraulic equipment, a research method of wear characteristics of spraying material layer of multi-axis CNC machine tool hydraulic equipment based on discrete element method was proposed. The discrete element method was introduced to analyse the wear characteristics of spraying material layer of multi-axis CNC machine tool hydraulic equipment. Based on the discrete element method, the contact model of spraying material layer of multi-axis CNC machining hydraulic equipment was established. The friction coefficient and wear rate of multi-axis CNC machine tool hydraulic equipment spraying material layer under different load and sliding speed analysed. The experimental results show that the accuracy of the proposed method is up to 99% and the analysis time is about 7 s.

Hardware, software and algorithmic ensuring of the hydraulic press equipment control system

An automated control system for hydraulic press equipment is designed and put into operation. Its block diagram, operation algorithm, program control interface for hydraulic press equipment is developed. The automatic control and measuring system, presented in the article, permits e to establish the optimal mode for controlling the technological casting process with crystallization of liquid metal under pressure, as well as the general change in pressure in the hydraulic system of the press during its operation. Keywords hydraulic press, control algorithm, pressure change, program correction, control system, interface

Експериментальне дослідження деформації пружно-гвинтового хона

One of the important issues in the development of agricultural engineering is to increase the efficiency of finishing processes of machining the surfaces of controlling parts of the hydraulic machines equipment and the fuel system of internal combustion engines. High accuracy and quality of parts influence the performance of functional indicators and the consistency of their performance. One of the processes of finishing machining is honing of precision holes. The factor that impacts the accuracy and quality of the machined hole is the ability to influence the process of formation of macrogeometry and microgeometry due to the flexibility of the process. The quality of the micro-relief is influenced by the kinematics of the formation of a grid of traces. The formation of macrogeometry, in turn, is influenced by the principle of formation of geometric production lines, taking into account copying of existing deviations and the transfer of wear of diamond-abrasive bars. To level the impact of existing deviations of the machined hole it is necessary to carry out a flexible control of the process of adjusting the radial size. To ensure the flexibility of the process of honing holes, a helix honing tool is proposed, which eliminates the shortcomings of the existing diamond-abrasive tool by using elastic deformations to increase the radial size and placement of diamond-abrasive bars at an angle of 45º. To study the process of adjusting the radial size of the helix honing tool, the calculated scheme of elastic deformation of the geometric axis and a mathematical model describing the deformation process are presented. An experimental setup of the deformation of the helix honing tool in the axial direction is also given. As a result of the experimental study of the helix honing tool, the theoretical and experimental dependence of the magnitude of the increase in diameter and the force of deformation on the axial elastic deformation is determined. There are also mathematical models obtained as a result of the experimental study of the dependence of the diameter increase on the magnitude of the applied force and axial elastic displacement.

Modern Techniques for Remanufacturing Hydraulic Equipment in the Context of Circular Economy and Energy Efficiency

The article presents several current methods of remanufacturing hydraulic components, a trend that is encouraged, on the one hand, by concerns about reducing material consumption in the context of the circular economy - some of these materials being expensive or in short supply. On the other hand, remanufacturing by modern methods can lead to a decrease in energy consumption in the devices concerned, due to obtaining shapes that are difficult to achieve by classical procedures. Among the remanufacturing processes considered there are additive manufacturing, metal coating, reverse engineering, etc. An important step in the remanufacturing process is testing of components, which certifies the achievement of performances at least equivalent to those of the original products. To this end, the article presents a test bench solution with the help of which tests can be carried out on hydraulic devices such as hydraulic pumps and (linear or rotary) motors, hydraulic directional control valves or other types of valves.

Research on wear characteristics of spraying material layer on hydraulic equipment of multi-axis CNC machine tool based on discrete element method

Research on wear characteristics of spraying material layer on hydraulic equipment of multi-axis CNC machine tool based on discrete element method

Capacitive–Inductive Magnetic Plug Sensor With High Adaptability for Online Debris Monitoring

A capacitive–inductive magnetic plug sensor for online condition monitoring is proposed in this article, which can achieve particle counting, debris measurement, and wear rate estimation. The sensor can detect capacitance and inductance parameters, the coil is the outer electrode to detect the dielectric change in capacitance mode, and the coil directly induces magnetic field disturbance in inductance mode. Through introducing a reference unit, Wheatstone bridge circuits are constructed to enhance the response to debris and reduce the interference of oil temperature and viscosity. A postprocessing circuit with filtering and amplifying functions is adopted to improve accuracy. The sensor output characteristics and debris position effect are studied through the experiment. The comprehensive analysis of the detection results in two modes can improve sensor adaptability and overcome the deficiency of low reliability based on a single detection method. This sensor can provide more accurate debris information for the fault diagnosis of hydraulic equipment and is of great significance for intelligent maintenance.

Universal programmable portable measurement device for diagnostics and monitoring of hydraulic and pneumatic equipment

The paper presents a new universal programmable portable measuring device (PMD) intended for the diagnostic and monitoring of hydraulic and pneumatic equipment. PMD offers a simple, complete, and efficient remote monitoring and diagnostic solution for hydraulic and pneumatic equipment. PMD is designed for measurement, recording, and processing of data as well as graphical visualization of registered results on a test stand or in the operating site of hydraulic and pneumatic equipment. PMD is designed to measure parameters used in servicing, repairing, monitoring, and diagnosing hydraulic and pneumatic equipment. Usually, fluidic characteristic quantities (pressure, flow rate, temperature), mechanical quantities (position, linear speed, rotational speed, force, torque, shaft power), and electrical quantities (voltage, current, power) is measured. PMD with WiFi communication is adopted to transfer measurement data via the Industry Internet of Things (IIoT) technology to remote online monitoring and diagnostic hydraulic and pneumatic equipment. Sensors, controllers, and other devices are connected to the computing gateway via their respective protocols.

Pengujian dan Sistem Kerja Test Bench Hydraulic Pump Gear Type

Hydraulic system is one of the systems on the heavy equipment unit which is very important for students to understand. The problem that exists in the heavy equipment engineering laboratory at this time is that there is no hydraulic pump test equipment to determine whether the pump that has been repaired is in standard condition or not. To overcome the problems and to support the lecture process, the hydraulic pump test equipment was made. as a tool for testing the feasibility and specifications of the gear type pump. After all the design processes and assembling the required tools, a series of tests will be carried out. The form of tool testing is carried out in the form of pump flow liters per minute, pump pressure in various RPM variations. From the test results, it was found that at RPM 900 the pressure was 100 Psi Flow reading 11 and Flow rate 209, at RPM 1100 pressure 12 Psi Flow reading 15 and Flow Rate 285, At 1372 Pressure 14 Psi Flow reading 19 and flow rate 361, RPM 1500 Pressure 16 Psi Flow reading 19 and Flow rate 437

Influence of temperature fluctuation on friction inside hydraulic cylinder

This paper considers variety of hydraulic actuators. Also it shows analysis of hydraulic equipment. The contribution is important due to the fact that it determines influence of temperature on friction in hydraulic equipment. The paper examines the factors of reducing the performance of hydrofected machines during operation at low temperatures. The importance of the work is due to the fact that the effects of temperature on friction in hydraulic equipment are considered. An experiment was also conducted, due to which the influence of temperature on the wear resistance of the hydraulic cylinder was revealed.

Performance improvement methods of hydroficated machine under refrigeration

In this paper, the problem of the influence of climatic conditions on the performance of a Hydraulic gear is considered. The importance of the work is due to the fact that the methods for solving the problem are proposed, namely, the use of preheating for a Hydraulic gear and an internal combustion engine under refrigeration. The use of hydrofected self-propelled vehicles in the northern regions in winter is considered. The factors determining the technical and economic indicators of hydrofected machines are revealed. The influence of negative temperature on the physical and mechanical properties of hydraulic equipment materials is also considered. Three main directions have been identified in which temperature affects the hydraulic drive. An experiment was conducted in which the dependence of the performance of the machine was revealed using a preheating device for the working fluid and without the device.

ABOUT AUTOMATION OF CONTROL AND DIAGNOSIS OF TECHNICAL STATE OF HYDRAULIC DRIVES OF INDUSTRIAL EQUIPMENT

The main tasks of automated control and diagnostics of the technical condition of hydraulic drives are formulated, criteria for assessing the technical condition of a hydraulic drive as a whole and its individual devices are considered, examples of test operating modes for hydraulic drives with a guide and proportional hydraulic equipment are given.