Load-Carrying Capacity of Austempered Ductile Iron (ADI) Gears : Influence of Surface Integrity on Transmitted Load Capacity

High-speed rotating system development has drawn considerable attention of the researchers, in the recent past. Foil bearings are one of the major contenders for such applications, particularly for high speed and low load rotating systems. In foil bearings, process fluid or air is used as the working medium and no additional lubricant is required. It is known from the published literature that the load capacity of foil bearings depend on the operating speed, viscosity of the medium, clearance, and stiffness of the foil apart from the geometric dimensions of the bearing. In case of foil bearing with given dimensions, clearance governs the magnitude of pressure developed, whereas stiffness dictates the change in radial clearance under the generated pressure. This article deals with the effect of stiffness, clearance, and its interaction on the bump foil bearings load-carrying capacity. For this study, four sets of foil bearings of the same geometry with two levels of stiffness and clearance values are fabricated. Experiments are carried out following two factor-two level factorial design approach under constant load and in each case, the lift-off speed is measured. The experimental output is analyzed using statistical techniques to evaluate the influence of parameters under consideration. The results indicate that clearance has the maximum influence on the lift-off speed/ load-carrying capacity, followed by interaction effect and stiffness. A regression model is developed based on the experimental values and model is validated using error analysis technique.

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Static characteristics of misaligned multiple axial groove water-lubricated bearing in the turbulent regime

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650116657757 ◽

2016 ◽

Vol 231 (3) ◽

pp. 385-398 ◽

Cited By ~ 14

Author(s):

Ravindra Mallya ◽

Satish B Shenoy ◽

Raghuvir Pai

Keyword(s):

Reynolds Number ◽

Friction Coefficient ◽

Carrying Capacity ◽

Journal Bearing ◽

Load Capacity ◽

Turbulent Regime ◽

Load Carrying Capacity ◽

Static Characteristics ◽

Load Carrying ◽

Turbulence Effects

The static characteristics of misaligned three-axial water-lubricated journal bearing in the turbulent regime are analyzed for groove angles 36° and 18°. Ng and Pan’s turbulence model is applied to study the turbulence effects in the journal bearing. The static parameters such as load-carrying capacity, friction coefficient, and side leakage are found for different degree of misalignment (DM). The change in flow regime of the lubricant from laminar to turbulent and the increase in misalignment, improved the load capacity of the bearing. For lightly loaded bearings, the friction coefficient of the bearing increased with the increase in Reynolds number.

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Partially Textured Slider and Journal Bearing Analysis

Jurnal Teknologi ◽

10.11113/jt.v58.1553 ◽

2012 ◽

Vol 58 (2) ◽

Author(s):

T. V. V. L. N. Rao ◽

A. M. A. Rani ◽

T. Nagarajan ◽

F. M. Hashim

Keyword(s):

Friction Coefficient ◽

Coefficient Of Friction ◽

Carrying Capacity ◽

Journal Bearing ◽

Load Capacity ◽

Load Carrying Capacity ◽

Load Carrying ◽

Bearing Analysis

The present study examines the influence of partial texturing of bearing surfaces on improvement in load capacity and reduction in friction coefficient for slider and journal bearing. The geometry of partially textured slider and journal bearing considered in this work composed of a number of successive regions of groove and land configurations. The nondimensional pressure expressions for the partially textured slider and journal bearing are derived taking into consideration of texture geometry and extent of partial texture. Partial texturing has a potential to generate load carrying capacity and reduce coefficient of friction, even for nominally parallel bearing surfaces.

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Load-Carrying Capacity of Short Concrete Columns Reinforced with Glass Fiber Reinforced Polymer Bars Under Concentric Axial Load

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.b2372.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 1712-1719

Keyword(s):

Carrying Capacity ◽

Load Capacity ◽

Plain Concrete ◽

Concrete Columns ◽

Reinforcement Ratio ◽

Load Carrying Capacity ◽

Rc Columns ◽

Gfrp Bars ◽

Glass Fiber Reinforced ◽

Load Carrying

In this paper, 1 group of plain concrete square columns 150×150×600 mm and 11 groups of concrete columns reinforced with glass fiber reinforced polymer (GFRP) were cast and tested, each group contains of 3 specimens. These experiments investigated effect of the main reinforcement ratio, stirrup spacing and contribution of longitudinal GFRP bars on the load carrying capacity of GFRP reinforced concrete (RC) columns. Based on the experiment results, the relationship between load-capacity and reinforcement ratio and the plot of contribution of longitudinal GFRP bars to load-capacity versus the reinforcement ratio were built and analyzed. By increasing the reinforcement ratio from 0.36% to 3.24%, the average ultimate strain in columns at maximum load increases from 2.64% to 75.6% and the load-carrying capacity of GFRP RC columns increases from 3.4% to 25.7% in comparison with the average values of plain concrete columns. Within the investigated range of reinforcement ratio, the longitudinal GFRP bars contributed about 0.72%-6.71% of the ultimate load-carrying capacity of the GFRP RC columns. Meanwhile, with the same configuration of reinforcement, contribution of GFRP bars to load-carrying capacity of GFRP RC columns decreases when increasing the concrete strength. The influence of tie spacing on load-carrying capacity of reinforced columns was also taken into consideration. Additionally, experimental results allow us to propose some modifications on the existing formulas to determine the bearing capacity of the GFRP RC column according to the compressive strength of concrete and GFRP bars.

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