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Hydrodynamic Journal and Thrust Bearings
Published in Maurice L. Adams, Bearings, 2018
The term thrust bearing is synonymous with its two functions: (1) to carry the cumulative sources of rotor axial loads (e.g., from gears, turbomachinery stages, electric-motor magnetics, rotor dead weight on vertical rotors) and (2) to hold the rotor in its designed axial position with respect to the non-rotating portion of the machine. The simplest and most basic form of a hydrodynamic bearing is the fixed-pad slider bearing, illustrated in Figure 1.12 with its fluid-film pressure distribution and theoretical foundation. Like all hydrodynamic fluid film bearings, the slider-bearing functions by lubricant being drawn into a converging wedge-shaped space, producing fluid pressure that counteracts the applied bearing load while preventing contact between the parts in relative sliding motion. Virtually any converging film-thickness-distribution shape can so produce a load-supporting fluid film to separate sliding surfaces. For the thrust bearing employing fixed pads (as opposed to tilting pads), configurations having a uniform converging slope starting from the inlet is illustrated in Figure 7.36.
Introduction
Published in Mohamed Gad-el-Hak, MEMS, 2005
Thrust bearings support any axial loads generated by rotating devices such as turbines, engines, or motors. Current fabrication techniques require that the axis of rotation in MEMS devices lie normal to the lithographic plane. This lends a significant advantage in the design and operation of thrust bearings because the area available for the thrust bearing is relatively large as defined by lithography, while the weight of the rotating elements will be typically small due to the cube-square law and the low thicknesses of microfabricated parts. For these reasons, thrust bearings are one area of microlubrication where solutions abound and problems are relatively easily dealt with.
Compressors
Published in Don M. Pirro, Martin Webster, Ekkehard Daschner, Lubrication Fundamentals, 2017
Don M. Pirro, Martin Webster, Ekkehard Daschner
With a single impeller, or group of impellers, all facing in the same direction, there is an axial thrust because of the backward force exerted by the discharging gas on the rim of the impeller. This thrust force can be balanced internally by means of a balancing drum or dummy piston, but a thrust bearing must be used to support all or part of the thrust load and keep the impeller accurately located in the casing. Thrust bearings are generally angular contact ball, collar, fixed shoe, or tilting shoe type.
Dynamic analysis and frequency response of cylindrical roller bearing of an airflow root blower
Published in Cogent Engineering, 2022
Themba Mashiyane, Dawood Desai, Lagouge Tartibu
The roller bearings used in machinery come in different types such as cylindrical roller bearing, spherical roller bearing, tapered roller bearing, thrust bearing, etc. An airflow root blowers being one of such machines that operate in a compression range of 1.1–1.2 (Verma, 2014) and are used to discharge compressed air/demineralized water into a mechanical system at a steady flow rate, depending on the system requirement, it uses a cylindrical roller because the bearing has a high load-bearing capacity, and it is capable of operating efficiently under moderate speed and heavy-duty applications (Sehgal et al., 2000; Upadhyay et al., 2013; Sharma et al., 2014, 2015).
Turbo-drill thrust ball bearing raceway fatigue analysis based on the Dang Van criterion
Published in Australian Journal of Mechanical Engineering, 2021
Ruyi Gou, Xiaodong Zhang, Wenwu Yang, Yan Gong
As an important downhole motor, the turbo-drill can significantly improve the rate of penetration and ensure wellbore structure and drilling safety, it has tremendous technical and economic benefits (Fu, Zhang, and Fu 2000; Wang et al. 2016). The short working life of thrust bearing seriously restricts the application and promotion of turbo-drill. Many scholars sought the methods to increase the down-hole tools bearing service life, such as by optimising the bearing structure, changing the material of bearings and improving the lubrication method (Sexton and Cooley 2009; Lingwall, Sexton, and Cooley 2013; Yang et al. 2016).
Theoretical and Experimental Study of Transient Behavior of Spiral-Groove Thrust Bearings during Start-Up
Published in Tribology Transactions, 2020
Thrust bearings are used to support axial loads and have numerous applications in industry. In order to improve their performance, extensive studies have been conducted experimentally and theoretically. In recent years, the application of surface texture in thrust bearings has attracted wide attention. Spiral-groove thrust bearings, as a typical surface texture application, have shown excellent performance. Compared to most fixed geometry thrust bearings with a taper land, spiral grooves can also provide convergent wedges to generate fluid pressure, thus providing load-carrying capacity.