Effect of Specimen Ball Diameter on Contact Stress

2010 ◽  
Vol 37-38 ◽  
pp. 386-389
Author(s):  
Jing Ling Zhou ◽  
Guo Qing Wu ◽  
Xiao Yang Chen ◽  
Wei Nan Zhu
Keyword(s):  
Silicon Nitride ◽  
Theoretical Basis ◽  
Deflection Angle ◽  
Direct Influence ◽  
Test Rig ◽  
Contact Points ◽  
Pure Rolling ◽  
Ball Diameter ◽  
New Type ◽  
Bearing Ball

By using a new type pure rolling fatigue test rig with three contact points for silicon nitride bearing ball specimen, the contact deflection angle of specimen with three contact points is calculated. The effects of the center height and test ball radius on the specimen contact deflection angle are analyzed. The analysis indicates that the span of contact deflection angle is 0-0.181° while the center height is 1.2mm and the design radius is 6.35mm and the specimen radiuses change from 4mm to 8mm. The more contact deflection angle is, the more variation rang of test ball radius is. The contact deflection angle can be less than 0.2° while the center height is optimized. The contact deflection angle has a direct influence on the stress error of the specimen. It is less than 1% while the contact deflection angle is less than 0.2°. The research provides a theoretical basis for optimization of test rig structure size and increase of specimen’s extension and improvement of test precision.

Devise of the RCF Test Rig for Ceramic Bearing Ball by Design Methodology

2010 ◽  
Vol 44-47 ◽  
pp. 1773-1776
Author(s):  
Jing Ling Zhou ◽  
Guo Qing Wu ◽  
Xiao Yang Chen ◽  
Wei Nan Zhu ◽  
Yu Song Ren ◽  
...  
Keyword(s):  
Fatigue Test ◽  
Design Methodology ◽  
Function Analysis ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Test Rig ◽  
Ceramic Bearing ◽  
Pure Rolling ◽  
Bearing Ball

It is presented to apply the designing methodology in design of an accelerated pure rolling contact fatigue test rig for ceramic bearing ball. Starting with function analysis, the request and structure of test rig are analysed. Meanwhile, the form matrix table is established, from which many designing schemes can be obtained. In accordance with several kinds of innovation schemes, the appraised decision of product is analyzed. The specimen machine is made according to the design scheme in the design of innovation.

Inertial Effects in a Multiple-Ball Transmission

1960 ◽  
Vol 82 (4) ◽  
pp. 399-406
Author(s):  
W. S. Rouverol
Keyword(s):  
High Speed ◽  
Velocity Ratio ◽  
Multiple Point ◽  
Inertial Effects ◽  
Power Capacity ◽  
Wear Life ◽  
Pure Rolling ◽  
Ball Diameter ◽  
New Type ◽  
Steel Balls

A new type of mechanical variable-speed transmission, which owes its improved efficiency and wear-life to the utilization of multiple point contacts in pure rolling, has a power capacity in proportion to the maximum tractive forces and rolling velocities developed by a large number of small steel balls. Designing for maximum power capacity depends on finding the point at which the components of tractive force arising from inertial effects at high speed become so large as to interfere with the proper kinematic action of the balls. Consideration is given to the influence of a number of design and operating parameters, such as ball diameter, cage diameter, cage velocities, and velocity ratio.

Wear Analysis Using a Quick Stop Device

1992 ◽  
Vol 114 (3) ◽  
pp. 524-529
Author(s):  
D. C. Furze ◽  
B. J. Griffiths ◽  
M. C. Carrey
Keyword(s):  
Wear Test ◽  
Test Rig ◽  
Testing Method ◽  
Wear Analysis ◽  
New Type

This paper describes a new type of wear test rig which is based on a quick stop principle. The advantages of using such a rig and the associated testing method are described with respect to the analysis of prow formation.

Flow Velocity Coefficient Research on the Coexistence of Pipe Flow and Flow around Pipe

2011 ◽  
Vol 204-210 ◽  
pp. 746-749
Author(s):  
Hong Bing Gao ◽  
Nan Sun ◽  
Liao Yang ◽  
Yu Ma
Keyword(s):  
Flow Field ◽  
Theoretical Basis ◽  
Flow Simulation ◽  
Flow Speed ◽  
Test Rig ◽  
Flow Problems ◽  
Relative Roughness ◽  
Velocity Coefficient ◽  
Definition Of ◽  
Test Result

Based on Darcy - Weisbach route losses equation, this test is focused on the mixed-flow problems at low speed in big flow field, designing the experiment scheme, introducing its principle, and setting up the test rig. According to the test result data, we put forward the definition of flow speed coefficient and draw its curves, and described some related issues, such as reverse pressure phenomenon，reliability of flow simulation, roughness, and so on. The results showed that the flow speed in the pipe will get higher with the flow field increasing, and smaller relative roughness pipes. The flow speed coefficient x≤1 and its curves is monotone decreasing function and will be closer to a fixed value at last with V0’s increasing. This test will provide theoretical basis for increasing fluid energy’s utilization.

scholarly journals Kinematic analysis and simulation of a new type of differential micro-feed mechanism with friction

2019 ◽  
Vol 103 (1) ◽  
pp. 003685041987566
Author(s):  
Hanwen Yu ◽  
Xianying Feng ◽  
Qun Sun
Keyword(s):  
Mechanical Efficiency ◽  
System Structure ◽  
Advanced Technology ◽  
Ball Screw ◽  
National Defense ◽  
Integrated Electronics ◽  
Contact Points ◽  
Feed Control ◽  
Potential Applications ◽  
New Type

This article presents a new micro-feed mechanism, whose main transmission component is the nut–rotary ball screw pair. The screw and nut are driven by two motors, and they rotate in the same direction, with their movements enabling micro-feeding. The main contribution of the micro-feed mechanism is to avoid the inevitable low-speed nonlinear creeping phenomenon caused by the inherent properties of traditional electromechanical servo system structure, thus realizing high precision micro-feed. In this study, the motion state of the working ball is analyzed using the principle of differential geometry, the friction at the contact points is calculated, the balance equation for force and moment is established, the influences of the screw and nut on the kinematic parameters of the ball at different velocities and the differences in the motion states of the ball in different drive modes are studied, and the mechanical efficiency of the dual-driven ball screw mechanism is calculated. The potential applications of the new micro-feed mechanism and the results of numerical analysis can be applied to advanced technology fields such as robotics, suspensions, powertrain, national defense, integrated electronics, optoelectronics, medicine, and genetic engineering, so that the new system can have a lower stable speed limit and achieve precise micro-feed control.

scholarly journals PIP Preparation of Silica Fibre Fabric Reinforced Silicon Nitride-Based Composites using Polyhydridomethylsilazane

2005 ◽  
Vol 14 (4) ◽  
pp. 096369350501400
Author(s):  
Gong-jin Qi ◽  
Chang-rui Zhang ◽  
Hai-feng Hu ◽  
Chang-cheng Zhou
Keyword(s):  
Mechanical Property ◽  
Silicon Nitride ◽  
Three Dimensional ◽  
Matrix Interface ◽  
Interface Bonding ◽  
Pull Out ◽  
New Type ◽  
Ammonia Atmosphere ◽  
Fibre Matrix ◽  
Silica Fibre

A new type of composites, three-dimensional silica fibre fabric reinforced silicon nitride-based composites, were prepared by PIP method through repeated infiltration of polyhydridomethylsilazane and pyrolysis at 773-873K in ammonia atmosphere. The density of the composites reached 1.66g/cm3 after four PIP cycles, and the flexural strength was 56.3 MPa. The composites showed a near-brittle fracture mode without long fibre pull-out in the fracture surface. It was the relatively strong fibre/matrix interface bonding that led to the moderate mechanical property.

Structure of Smart Materials and its Application in Construction Industry

2014 ◽  
Vol 1022 ◽  
pp. 26-29
Author(s):  
Yong Hui Jia ◽  
Jia Xiao Heng
Keyword(s):  
Construction Industry ◽  
Experimental Research ◽  
Smart Materials ◽  
Theoretical Basis ◽  
Water Resistance ◽  
Detection Algorithm ◽  
Mechanical Analysis ◽  
Smart Sensor ◽  
Pzt Film ◽  
New Type

In this paper, the piezoelectric ceramic crisp, poor water resistance, resistance to external load capability is not strong lack of self-designed package more perfect a new type of "smart piezoelectric aggregate", to better address the PZT film resist unfavorable load , vulnerability and durability issues and other aspects; and further superior characteristics of piezoelectric smart sensing and drive integration of theoretical analysis, modeling, numerical calculations, mechanical analysis and experimental research; on this basis, based on the pressure and Experimental Research aggregate electric smart sensor / driver structural health monitoring and damage detection algorithm, the theoretical basis for the realization of the transition from the pilot study engineering applications to provide the experimental basis and technical support.

Experimental Research on Water Cushion Belt Conveyor

2013 ◽  
Vol 431 ◽  
pp. 88-92
Author(s):  
Ai Dong Zhang ◽  
Ri Cheng Xu ◽  
Yun Meng ◽  
Xun Fan
Keyword(s):  
Experimental Study ◽  
Influencing Factors ◽  
Experimental Research ◽  
Industrial Application ◽  
Theoretical Basis ◽  
Belt Conveyor ◽  
New Type ◽  
Air Cushion

Water cushion belt conveyor is a new type of continuous conveyor which develops from belt conveyor and air cushion belt conveyor .By experimental research on water cushion belt conveyor ,we can observe the condition of water cushion and accomplish the date acquisition of water cushion pressure .Analyzing the pressure ,we can get influencing factors of water cushion pressure and verify the feasibility of industrial application of water cushion belt conveyor .Combining theory study with experimental study ,provide theoretical basis and guide for the further progress of water cushion belt conveyor .

Dynamic Modeling and Validation of a Lorentz, Self-Bearing Motor Test Rig

2002 ◽  
Vol 125 (1) ◽  
pp. 156-166 ◽  
Author(s):  
L. S. Stephens ◽  
D.-G. Kim
Keyword(s):  
Dynamic Model ◽  
Permanent Magnets ◽  
Transfer Functions ◽  
System Model ◽  
Test Rig ◽  
Motor Test ◽  
Three Phase ◽  
New Type ◽  
Bearing Force ◽  
Good Agreement

A new type of self-bearing motor that uses Lorentz-type forces to generate both bearing force and motoring torque has been developed. The motor stator is of slotless construction with four three-phase windings. The motor rotor is constructed of 16 surface mounted permanent magnets (PM’s). The main advantage of the design is that it eliminates the tradeoff between motoring torque and bearing force with PM thickness as found in previous designs. This paper presents the dynamic model for the self-bearing motor and illustrates how the model is integrated into the overall system model of the motor test rig. The dynamic model is validated against experimentally measured transfer functions with good agreement between the two.

Design and Numeric Simulation of a Thermoacoustic Bi-Directional Turbine Test Rig

2019 ◽  
Author(s):  
Dongdong Liu ◽  
Yanyan Chen ◽  
Wei Dai ◽  
Ercang Luo
Keyword(s):  
Acoustic Field ◽  
Large Scale ◽  
Three Dimensional ◽  
Typical Result ◽  
Test Rig ◽  
Impulse Turbine ◽  
Power Generators ◽  
Numeric Simulation ◽  
Shaft Power ◽  
New Type

Abstract As a new type of acoustic-electric conversion method, bi-directional impulse turbine provides great potential for developing large scale and economic thermoacoustic power generators. A test rig for turbine tests in acoustic fields, which are provided through two reciprocating pistons, has been introduced. A three-dimensional numerical model has been used to simulate the whole system. The fundamental characteristics of the turbine in oscillating flow are analyzed. Impact of acoustic field features on the turbine performance has been studied. The results show that the performance is sensitive to the acoustic field. For the test rig, a typical result is that with a shaft power of 187 W, the turbine can reach an efficiency around 32%.

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