Gear Unit Research Articles

An Electric Drive for a Drilling Rig Top Drive System

The operation of a drilling rig top drive system (TDS) in drilling practice at a great depth or during the construction of a drill pipe stand in the case of failure of one of two motors is considered. In the existing kinematic scheme of most domestic and foreign TDSs, the two motors are mechanically rigidly connected to the drive shaft through a gear reduction unit. It is proposed to replace the gearbox with rigid mechanical connections with a double planetary gear reducer and, thereby, ensure the operation of the electric drive with two independent mechanical channels. Such a kinematic scheme with independent mechanical channels makes it possible to provide the drilling rig operation at great depths in the case of failure of one of the drives and when constructing pipes when disassembling the drilling string. Due to a wider range of torque control for each of the two channels, in the case of failure of one of the drives, the proposed scheme implements the indicated operating modes at a reduced speed, avoiding expensive downtime. The static mechanical characteristics of the TDS for the existing and proposed systems are presented. The calculation of the mechanical converter providing the required gear ratios for each of the mechanical channels is performed. The operation of the control system and power distribution unit of two drives is considered.

Design and output characteristic analysis for power head of truck-mounted drilling rig

Truck-mounted drilling rig is an important equipment for coalbed methane drilling construction, and the power head is one of the main actuators for truck-mounted drilling rig which has significant influence on technical feature of drilling rig. Now the power head of the rig is mostly driven by the motor + gear reduction unit to drive the main axle, the load change with the time, which had more influence on the rotation circuit. At the basis of analysis on load characteristics, a hydraulic control system with two-pump and two-circuit control was designed. The dynamic analysis model of the system is established, and the output characteristics of the system under no-load starting and on load starting are analysed. The analysis results show that: the response time of no-load starting pressure is 0.3s, the response time of on load starting pressure is 0.9s, the greater the load, the longer the response time; the output speed of the system reaches 120 r/min in the stable state.

Komposisi Hasil Tangkapan dan Tingkat Keramahan Jala Cumi (Cast Net) di PPN Kejawanan Cirebon Jawa Barat

Pelabuhan Perikanan Nusantara (PPN) Kejawanan Cirebon berada di bagian Timur Jawa Barat, merupakan pelabuhan tipe B yang didominasi oleh kapal dengan alat tangkap jala cumi (cast net) dengan jumlah sebanyak 123 unit kapal. Tujuan dari penelitian ini adalah manganalisis komposisi hasil tangkapan dan tingkat keramahan alat tangkap jala cumi (cast net) berdasarkan komposisi hasil tangkapan utama dan sampingan. Pengumpulan data dilakukan melalui wawancara dan survei. Data hasil tangkapan ikan dikumpulkan dari unit alat tangkap jala cumi (cast net) sebanyak 10 (sepuluh) unit kapal pada tahun 2018. Analisis data meliputi komposisi jenis hasil tangkapan dan tingkat keramahannya. Hasil penelitian menunjukan bahwa alat tangkap jala cumi (cast net) dengan komposisi hasil tangkapan didominasi oleh cumi-cumi sebesar 97% dan sisanya sebanyak 3% terdiri dari ikan lemuru, layang dan teri. Adapun ukuran hasil tangkapan cumi-cumi yang didaratkan di PPN Kejawanan Cirebon memiliki ukuran dengan kategori cumi besar 27-30 cm dengan jumlah total 79.324,64 kg dan cumi ukuran kecil 1-7 cm dengan jumlah total 18.411,29 kg. Nilai tingkat keramahan lingkungan pada alat tangkap jala cumi (cast net) diperoleh dengan jumlah nilai total 30. Berdasarkan nilai tersebut maka alat tangkap jala cumi (cast net) dikategorikan sebagai alat tangkap yang sangat ramah lingkungan.

Condition monitoring indicators for pitting detection in planetary gear units

Condition monitoring indicators for pitting detection in planetary gear units

Design solutions overview of single-stage universal gear reducers

Today, for almost all products, the appearance is very important. Thus, for example, the appearance of universal gear reducers was not given so much attention, but today there are many very interesting solutions of shape, colour and graphic design. It should have in mind that universal gear reducers have much complex construction comparing them with special gear reducers. In the same time, they have to provide different positions and way of mounting and different speeds with different powers (torques) at the output shaft. Particularly, it should be noticed, that within all universal gear reducers single-stage gear units are nowadays increasingly used because their gear ratio values are increased (values of gear ratio can go up to 15) so that these reducers largely cover most of the two-stage gear reducers with their gear ratio values, so thereby their exploitation is significantly increased. Single-stage gear reducers are very simple products, and today there is a large number of manufacturers of such product. However, their mounting dimensions and way of mounting are not defined by a standard, so there is a variety of units with different dimensions and way of mounting. Although, most manufacturers look up to dimensions of leading manufacturers (usually SEW) in order to ensure greater exchangeability of their gear units. It is interesting to note, that most manufacturers tend to adopt the design of housing that will be substantially different from competing solutions. The reason is probably to avoid the possibility of being accused of copying someone else’s solution. However, there are manufacturers that retain almost identical housing design as a competing solution (probably they bought the licence or the solution is copied without permission). This paper considers only the design solutions of single-stage gear reducer in order to indicate the expected directions of their further development.

Pneumatikus munkahengerek speciális alkalmazása

The Aventics Hungary Ltd. has organized the twelfth International Aventics Pneumobile Competition, which includes the design and construction of pneumatic-drive. We participated in this year's competition, with my team at the University of Miskolc. In pneumobiles, the first task to be solved is to convert the alternating motion of the cylinders into rotary motion. I designed this for this purpose, a unique gear rack-gear unit that has been the heart of our pneumobile for years.

Development of the Technology for Manufacturing and Introducing a New Class of Tools with CVD Diamond for Grinding High-Precision Gear Wheels of Special Gear Units

Development of the Technology for Manufacturing and Introducing a New Class of Tools with CVD Diamond for Grinding High-Precision Gear Wheels of Special Gear Units

Розробка технології виготовлення та впровадження нового класу інструменту з CVD-алмазу для шліфування високоточних зубчастих коліс спеціальних редукторів

Розробка технології виготовлення та впровадження нового класу інструменту з CVD-алмазу для шліфування високоточних зубчастих коліс спеціальних редукторів

Simulation model of oscillations of the “sun gear – satellites” pair of turboprop engine planetary reduction gearbox in the presence of defects of tooth flanks

Defects of planetary reduction gearboxes of turboprop engines often cause excitation of high-frequency oscillations that bring about failures of compressor structural elements. The vibration behavior of these reduction grarboxes is a broadband process with the presence of a large quantity of vibration components, which significantly complicates the search for informative diagnostic indicators of defects. In order to simplify the procedure of identifying the vibrations caused by defects of toothed gearing a simulation model of the vibration behavior of a turboprop engine differential gear unit is proposed. The model takes into account kinematics and design of the gearbox, determines the structure of its vibration behavior in the presence of defects on the tooth flanks. Using the example of a commonly occurring defect in the form of wear of the teeth of the solar gear satellites pair the adequacy of the model to the actual vibration behavior of the mechanism is shown.

Low Friction and Low Viscosity Final Drive Oil

<div class="section abstract"><div class="htmlview paragraph">The new lubricant was newly developed for differential gear unit to contribute to all friction factors/conditions (Boundary, Hydrodynamic & those Mixed Lubrication) even if the differential gear is operating under very severe conditions such as high-gear-contact pressure and highly sliding speed. The main concept of development was selecting and formulating the optimized additives for severe lubrication conditions in order to achieve the best balance between thinner-film thickness and extreme pressure performance. In conclusion, by the application of both synthetic base oil instead of mineral one and activation technology of MoDTC in spite of ZnDTP free formulation, it is finally realized to reduce the torque of final drive unit by 40% and it can be estimated the 0.5% of CO<sub>2</sub> reduction in actual vehicles.</div></div>

Dynamical model of HEV with two planetary gear units and its application to optimization of energy consumption

A hybrid electric vehicle (HEV) that uses multiple planetary gear units with clutches as transmission system is advanced for the powertrain performance, because the operation of the clutches can lead to distinct operating modes, and the induced possible operating modes provide additional freedom to deal with the energy optimal control problem. Under each operating mode, the powertrain mechanical system has specific dynamical behavior. In order to develop model-based optimization schemes that can tackle the transient operations of the vehicle, exact dynamical modeling is investigated focusing on a hybrid powertrain system that uses a two-planetary-gear transmission box with two clutches. It shows that according to the states of the two clutches, the powertrain system has the power-split mode, parallel mode and the electric vehicle (EV) mode. Finally, an analysis for the calculation of the desired driving torque and its application to the dynamic programming (DP)-based energy management indicate the significance of the developed exact dynamical models.

Analysis of axial forces in harmonic drives of mining machines and heavy industrial equipment

Special features of arising axial forces in heavy-duty harmonic gear drives with the disk wave generator are described. As a result of research performed, it is found that kinematic pairs formed by the wave generator disks and the flexspline serve as a source of axial forces in heavy-duty harmonic gear drives. The disclosure of physics of the effects taking place in the elastic kinematic pairs: disk – flexspline, determination of nature of axial forces acting in the area of the wave generator under load, allows uprating of the performance data, lifting of load-carrying capacity restrictions and providing full development of heavy-duty harmonic gear drives. The force analysis of the results of the experimental research of axial forces in the heavy-duty harmonic gear drives with the disk wave generator, arising in kinematic pairs: disk – flexspline - has been carried out. Axial forces were measured employing the method of strain gauging of the flexsplines of the heavy-duty waveform gear reduction units tested under the laboratory and production-line conditions of heavy engineering, with the adjustable load conditions. Functional connection of axial forces values with the harmonic gear drives design features has been established, depending on the external loads.

Using Arduino in Physics Teaching: Arduino-based Physics Experiment to Study Temperature Dependence of Electrical Resistance

Nowadays, the rapid developments in science and technology have an impact on education as well as on all gear units. The integration of technology into the education process offers effective opportunities, particularly in the fields of STEM (Science, Technology, Engineering and Mathematics). In this context, Arduino platform has started to be used as a low cost, easy to use microcontroller in physics teaching. In this study, an Arduino-based physics experiment that can be used in physics laboratories was designed. We have used Arduino platform to study temperature dependence of electrical resistance and to define the temperature coefficient for a conductor. Experimental data were collected using the Arduino ohmmeter and a temperature sensor. The resistance-temperature curve obtained is in the expected character and the temperature coefficient is in the expected value. With this experiment, the student can easily observe the temperature change of the conductor's resistance and calculate the temperature coefficient of the resistance. The Arduino-based apparatus is presented as a simple and low cost alternative to physics laboratories.

Analysis of the influence of direction of helical teeth in the universal helical gear reducer on service life of the bearings that support the reducer shaft

The paper analyses the problems of the influence of direction of helical teeth in the universal helical gear reducer on service life of the bearings that support the reducer shaft, i.e. on the overall load carrying capacity of universal gear reducer. Directions of helical teeth for all gear units is adopted in that way that the overall axial force at the reducer shaft is lowest as possible, i.e. axial forces of a shaft are in counterbalance. It is a practice the same output gear pair is used within a helical gear reducer made in universal casing for two- and three-stage gear reducer. However, these gears are produced with different directions of helical teeth in order to obtain the lowest axial force on the fifth geared shaft. However, some gear reducer manufacturers, trying to simplify the production and reduce the number of manufactured components, produce the gears with the same helical teeth direction for both two- and three-stage gear reducers. In that way, they do not reduce the value of axial force on the fifth geared shaft in three-stage gear unit, but they make addition of axial forces that certainly affects the service life of the bearings and thus the overall load carrying capacity of the gearbox. Analysing the concrete case, this paper researches the justification of implementation this procedure.

OVERFISHING AND OVERCAPACITY SMALL SCALE FISHERIES IN SEMARANG CITY

Fisheries in Semarang City are dominated by small-scale fisheries. This is indicated by the use of the largest fishing fleet of 10 gross tons operating near the coast. This study aims to analyze the status of small-scale fisheries in Semarang City for sustainable management. Sustainable management is management that guarantees the availability of natural resources and environmental services for future generations. The study was conducted for three months, namely September-November 2018 in the coastal waters of Semarang City, which was part of the Fisheries Management Region (WPP) 712. The method used in this study is the analysis of time series surplus production, namely data from the catch (ton/year) and the number of fishing gear (unit) within 10 years (2007-2016), to calculate the catch per-unit effort (CPUE), maximum sustainable yield (MSY), optimum effort (fopt), utilization rate (TP) and capacity level (TK). This study was obtained results of a downward trend in CPUE; the existing fishery catch or production in 2016 has exceeded the MSY value is 479 tons/year (Schaefer) and 439.11 tons/year (Fox); utilization rate of more than 100% which is 108-127% (Schaefer) and 118-138% (Fox), so that small-scale fisheries in Semarang City are at the level of over-exploited. Based on the fopt analysis, the number of fishing gear used (fexisting) has exceeded the optimum effort with a fishing capacity exceeding 100%, so that small-scale fisheries in Semarang City have experienced overcapacity.

Generator System on the Basis of Segment Wind Generators of Synchronous-Inductor Type

A new type of wind power generation systems with increased reliability due to the absence of a reducer while maintaining the main characteristics of the gear units is proposed. The main difficulties of realization of these installations are revealed, ways of their overcoming by use of new technical solutions are specified. Methods of construction and application of the offered devices are offered

МАТЕМАТИЧЕСКАЯ МОДЕЛЬ ИСПОЛНИТЕЛЬНЫХ МОДУЛЕЙ ЗАХВАТНЫХ УСТРОЙСТВ РОБОТОВ

Today, the task of increasing the drive unit technical characteristics of robot gripping devices is relevant. In many respects, the drive motor and gear unit determine the quality of work of such modules, which can introduce additional elasticity, backlash and friction into the system. In turn, backlash and friction in the control loop decrease the speed and accuracy of the mechatronic module and can cause self-oscillations. However, significant progress in hardware performance of mechatronic and robotic systems makes it possible to more accurately estimate and control the force and torque state parameters in the output link and to carry out active algorithmic compensation for the effects of friction and elasticity.
 Such observers are usually based on detailed mathematical models and allows to implement force control without the use of special sensors, which is especially important in advanced gripping devices due to the requirements imposed on the mass-dimensional parameters of the product. Therefore, the purpose of this article is to make a general mathematical model of the robot drive unit with a rational relationship of complexity and accuracy. The models’ parameters should be easily identified from the constituent elements of passport data or the experiment results. The model should allow estimating the state parameters of mechanical transmission in real time; take into account the main friction effects. However, it should be simple enough for analytical conclusion and numerical modeling. As part of the article, various friction models are considered. On the basis of this analysis, a modified friction model is proposed. It makes possible to estimate the state parameters of mechanical transmission in real time. It is built into the general mathematical model of the mechatronic module. The results of mathematical simulation are close to experimental data. The considered drive unit mathematical model can be used to identify the state parameters of the mechatronic module in real time and implement force control based on estimation. In addition, the obtained model allows to conduct mathematical simulation of the robot taking into account the drive unit dynamics.

Differential twin-engine automobile electric drive

This article considers work stability of a system with two-channel regulation of an autonomous electric drive’s speed, where the first channel is a high-torque drive, where the engine is connected through a gear unit with reducing transfer factor; and the second – high-speed with the similar motor is directly connected. The power summation is realized by using the differential gear unit. It is shown that the stable work can be achieved by a fixation of a speed setting through one channel, and the regulation through the other channel at the same time; control algorithms are shown. Optimal values of transmission ratio of high-torque drive gear unit j = 4 are defined, as well as a turn-on factor (rate of participation in transient process) of high-torque motor with its transient process time minimum.

Research of wear resistance of the composite coverings applied by a method of electric contact sintering

Intensity of wear process is one of the basic characteristics defining durability of mobile connections. To study wear resistance of a «roller pin», conditions close to real conditions of operation of the given unit should be recreated. Axes of running gears of wood machinery are subject to wearing due to abrasive friction. Friction is one of the most widespread processes; it accompanies any relative movements of adjoining bodies or their parts. The purpose of the present research is the substantiation of application of composite coverings for enhancement of running gear unit durability.

The development of realia for the planetary gear unit to improve students’ understanding on the basics of automatic transmission

This study aims to design and develop a real model of a planetary gear unit providing three kinds of simulation for the basic configurations of the planetary gear unit in which one component member is locked, two members are held together, and two input members works. This is a research and development (R&D) to develop a realia of the planetary gear unit for the learning of automatic transmission basics. The realia is expected to demonstrate how the configurations in which one component member is locked, two members are held together, and two input members moves. This study was carried out through ten stages, namely analyzing potentials and problems, needs analysis, product design, focus group discussion, product development, pilot study (small-scale field test), product revision, large-scale field test, product revision, and final product. The data were collected by questionnaires and were analyzed quantitatively. The product of this study is learning media in the form of realia made of acrylic so that the components are clearly visible and the work of basic configurations of the three gears in the planetary gear unit is easy to understand. These basic arangements can be operationalized on the learning media by applying brakes to the ring, carrier, and sun gears and applying cluthes between the sun and carrier gears, the sun and ring gears, and the carrier and ring gears. Evaluated from its performance, the realia of the planetary gear unit can work well. The shaft can rotate well though some friction generated, the clutch and brake can work on its function, as well as the constituent gears can rotate as its real version does. This is reinforced by the responses from the material and media experts that reveal the product meets the very feasible category.