Papers by Keyword: Wheel

Abstract: The purpose of the work is to quantify and predict the influence of inhomogeneity of local properties on the overall behavior of the selected casting aluminum wheel and knuckle in different loading cases. Smooth and notched tensile specimens and torsion specimens are extracted from different positions in the wheel and knuckle and tested. The dependences of the flow stress, the fracture strain, and the S-N curve on position for specimen extraction are evaluated. Metallographic investigations are performed to reveal the relations between microstructure/microdefects and the mentioned properties. A damage model based on a triaxiality-dependent fracture strain is calibrated and used to simulate the specimens and component tests. The simulations of static wheel tests and knuckle fatigue tests are performed with position-dependent material parameters. The prediction of the component tests is compared with the experimental results.

Abstract: The article presents the results of the study of the quality parameters of the precise hole, depending on the size, spatial location and condition of the contacting surfaces, the parameters of the state of the contact zone, during finishing grinding. The correlation between the processing modes and the current parameters of the contact zone during internal grinding is established. Dependencies describe the flow cross-feed for the i-th turn increment of the depth of micro-cutting, compensation of radial material removal previous turn, deterioration of the wheel, the increment of the elastic and thermal strains. At the same time, the depth of micro-cutting and the increment of elastic and temperature deformations affect the values of the radial wear of the tool and the radial removal of the material. The equation of displacement balance is developed for discrete processes of hole processing with abrasive tools, during which the analyzed surface area comes into contact with the abrasive tool periodically.

Abstract: In recent years, high speed railway technology has developed rapidly in China. Long routing of high-speed trains, low temperatures, corrosive environments and sand damage are unique to China’s operating environment. As an important safety component of rolling stock, the safety and reliability of the wheels is of deep concern and high value. It is significant to carefully study and systematically summarize the damage from different failure types in high-speed railway wheels under current conditions, and determine the influencing factors and mechanisms of wheel failures in order to improve railway operation safety. In this paper, the damage forms of high-speed railway wheels in China are introduced, and the main influencing factors of wheel failure are discussed in combination with wheel damage characteristics. What’s more, damage mechanism is analyzed aiming at providing theoretical references for reducing failure rate and improving train operation quality.

Abstract: Dynamic force that strains on the rail and the wheel occurs. In case of wheel flats, during wheel and rail interaction, exposure time of dynamic forces acting in contact is very short and depends on the railway vehicle speed and the length of flat.Results obtained from a method that uses mathematical model of a system “Railway Vehicle Wheel-Track” and the simplified method to determine a vertical impact force of wheel with flat and rail interaction are presented in this article.The results of the mathematical and physical results of this system are analysed and presented.

Abstract: Productivity of internal grinding processes is limited by wheel-workpiece contact area and high temperature generated during grinding. Existing internal grinding methods do not guarantee presence of coolant liquid in the heat generation zone. Usually coolant liquid from external nozzles could not penetrate turbulent air flow around grinding wheel. Assembled wheel with radially mobile segments allows increasing contact area but needs to be supported by more efficient heat evacuation system. New grinding wheel and method of internal grinding are developed and evaluated. New tool generates high speed hydrodynamic circular flow and dynamic wedges of coolant liquid in the cutting zones.

Abstract: This paper proposes a design of transformable wheel for enhancing mobility. Mobility evaluation is performed by mechanical theories as stability margin and obstacle overcoming and its calculating methods are used for simulations. A feasibility of suggested transformable wheel is investigated by simulations. The mobility is able to verify by stability margin angle and ability of climbing up an obstacles which is higher than radius of wheel. Simulation results show that suggested transformable wheel can help overcoming a mobility limitation of former designed robot which is with non-transformable wheel.

Abstract: Micro-arc oxidation technology is a new type of metal surface treatment technology. With a large area of die casting magnesium alloy wheel surface treatment as an example, the practical production and application of micro-arc oxidation technology of magnesium alloy is discussed, Surface treatment technology production line is designed, The main equipment and process piping required for production line is introduced in detail. By the study of current and voltage which have a large effect on the craft of micro-arc to magnesium alloy, in the end a kind of electric parameters of micro-arc oxidation about magnesium alloy was optimized and film quality for testing. The micro-arc oxidation technology has been proved practically an appropriate technology for Mg alloy wheel hub and reference for the mass production used for a large area of magnesium alloy surface treatment technology and equipment design.

Abstract: Study the property and resistivity of Low-pressure semi-solid die casting ( LPSSDC) aluminum wheel hub after heat treatment. The Brinell hardness has reached more than 100HB in all position. Tensile properties at inner rim and outer rim are both reached 280MPa. The result of resistance analysis on LPSSDC aluminum wheel hub is below. The resistivity of the material is only influenced by the supersaturated solid solution (SSSS), GP zone, metastable phase β 'and stable phase β (Mg₂Si). The resistivity has a decline during aging 0-0.5h and 0.75-8h, and an increasing during 0.5-0.75h. The resistivity remains stably when the decomposition of the solid solution achieved a dynamic balance after 8h aging time.

Abstract: This article describes the process of designing and testing the accuracy of trajectory following for omnidirectional mobile robot Odin. It explains the relation between mobile robotic stair climbing system with shaped wheels and omnidirectional wheels, which are used together in a combined locomotive system. It is presented by the conception study only on account of realization of the simplified chassis with the omnidirectional wheels for testing mechanical parameters and the accuracy of the trajectory ride. The omnidirectional mobile robot Odin was built based on a simplified chassis with omnidirectional wheels and with the modular manipulator Schunk mounted on top. The article concludes with a description and comparison of the achieved results by testing the accuracy of the trajectory ride for the simplified chassis and for the omnidirectional mobile robot Odin.

Abstract: The article describes sensory subsystem required for proper operation of a special segment wheel designed for smooth driving both on a flat surface and on stairs. This subsystem contains two 2D laser scanners Hokuyo oriented towards stairs that provide point clouds for further processing. The main part of the article deals with the algorithm for detection of stair features (surfaces of stair treads and risers) in the data, including initial noise filtering. The conclusion provides practical testing performed on few real staircases and evaluation of the results.