National Repository of Grey Literature 5 records found  Search took 0.00 seconds. 
Wear analysis of the sliding surface material of large-scale hydrostatic bearings
Daněk, Lukáš ; Robenek, Dětřich (referee) ; Svoboda, Petr (advisor)
This thesis focuses on the experimental investigation of the wear behavior of sliding surface materials in large-scale hydrostatic bearings during oil supply failure. The aim is to clarify the influence of materials and surface treatments on friction and wear. For this purpose, a testing methodology was designed and implemented in laboratory conditions. An experimental module was developed for the tribometer to simulate a critical state and a new procedures were established for evaluating the behavior of the contact. Wear results were observed using a profilometer, precise scales, and a microscope. A set of suitable materials for pad sliding surfaces was created, which were tested under critical conditions. The selected materials were representatives of construction steel and anticorrosion treatments (galvanization), soft and hard (aluminium) bronzes, composite bearing linings (Babbitt), polymers (UHMWPE), and composite materials (PTFE). The experimental results show the dependence of friction on sliding velocity, wear rate, and other phenomena repeatedly measured on a statistical sample of selected materials. The final result is a list of characteristics, limitations, and recommendations for the tested sliding materials, which can be used for more effective design and operation of large-scale hydrostatic bearings.
Optimization of hydrostatic bearing pad geometry using CFD simulation
Dryml, Tomáš ; Vimmr, Jan (referee) ; Michalec, Michal (advisor)
The master's thesis deals with the optimization of hydrostatic bearing pad geometry using CFD simulation and experimental measurements. By combining experimental and numerical approaches, the effect of variation of hydrostatic bearing recess shape and depth on individual operating parameters is investigated. The effect of geometry variations is determined by numerical simulations which have been validated with experimentally obtained data. The results show that the ideal recess depth should correspond to 20-50 times the lubrication layer height The simulations also show that depth variation has a significant effect on the operating parameters. In contrast, the variation of the recess shape does not significantly affect the operating parameters of the bearing. The design of the optimum geometry of the hydrostatic bearing is particularly important because it can bring significant financial and energy savings associated with the operation of (especially large-sized) hydrostatic bearings.
Hydrostatic bearings for wind energetics
Procházka, Michal ; Foltýn, Jan (referee) ; Michalec, Michal (advisor)
This bachelor thesis deals with the bearing of the main rotor shaft of a wind turbine using hydrostatic bearings. Wind turbines come in many designs and the thesis then determine the operating parameters and bearings used in horizontal axis turbines of different installed power outputs. Currently, repairs, as well as servicing of bearings, are very costly and affect the operation of the entire power plant. Hydrostatic bearings offer advantages that could reduce the failure rate of wind turbine bearings. The operating parameters of turbines of different outputs were used to calculate the selected hydrostatic bearings. The results shows that the use of this type of bearings is possible for turbines with different power outputs, but higher efficiency is estimated for larger turbines (for example 8 MW turbine). The energy consumption of bearing, required to drive the hydrostatic bearings, reaches 0,03 % of the total output, compared to 0,39 % for the smaller 55 kW turbine. The calculation has been simplified in the initial energy performance estimation and further steps could include bearing geometry optimization or extending the operating parameter range of the wind turbines.
Design of hydrostatic bearing for theater turntable
Foltýn, Jan ; Robenek, Dětřich (referee) ; Svoboda, Petr (advisor)
This thesis deals with the issue of hydrostatic bearings. The aim was to design a test rig for an axial hydrostatic bearing. The axial hydrostatic bearing was calculated and designed with respect to the function of the tester. The construction of the test equipment was further supported by calculations of the main parts together with FEM analyses. The design was also accompanied by an introduction to the hydraulic parts of the hydrostatic bearing, which took place in consultation with Bosch Rexroth. The aim of the work, the design of a test device in a scale of 1:10, was completed. The following results from hydrostatic bearing tests will allow the introduction of new procedures in the production of turntables mounted on a hydrostatic bearing. Examination of operating conditions and permissible assembly inaccuracies will make it possible to reduce the production requirements for bearing mounting.
Design of CES 200 turntable with hydrostatic bearing
Záviška, Petr ; Solař, Martin (referee) ; Blecha, Petr (advisor)
This diploma deals is occupied with design of the heavy rotary table with hydrostatic bearing of table. In introductory part of deals the design part are described, for exampel. tipes of bearings, drive and etc. In other parts the design of rotary table with hydrostatic bearings is described.