Torsional stress state in a hollow shaft with longitudinal slots

In general engineering practice, one key factor in designing a motor built-in high-speed spindle is to assemble the motor rotor and shaft by means of hot-fit to form a new rotor-shaft assembly. In this paper, the dynamic analysis of a hot-fit rotor in a rotor-shaft assembly by using 3D contact element is proposed. Contact pressure between the rotor and the shaft is firstly calculated through contact theory. The stress state is thus determined. The finite element modal analysis then follows with the stress state as a pre-stressed condition. The accuracy and the validity of the finite contact element results are verified by theoretical formulation, equivalent static analysis and experimental modal testing. The results presented herein indicate that it is accurate and effective in analyzing the dynamic behavior of the rotary shaft system with a hot-fit component by using contact element.

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Deformation Behaviors of Partial Diameter-Enlargement Part Worked under Combination Loading of Torsion and Pressure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.473.30 ◽

2013 ◽

Vol 473 ◽

pp. 30-34

Author(s):

Xia Zhu ◽

Keiji Ogi ◽

Manabu Takahashi ◽

Kazuki Mori ◽

Nagatoshi Okabe

Keyword(s):

Simulation Analysis ◽

Processing Method ◽

Stress And Strain ◽

Torsional Stress ◽

Processing Conditions ◽

Analysis Method ◽

The Finite Element Method ◽

Hollow Shaft ◽

Deformation Behaviors ◽

Combination Loading

We have proposed a new cold processing method to form a partial diameter-enlargement part in a hollow shaft. Using the processing method, the diameter-enlargement part with a large deformation is formed easily by applying compressive stress at yield stress level and cyclic torsional stress on two ends of specimen. In the present paper, processing experiments were conducted using the processing machine developed originally based on the processing principle, and deformation behaviors on the diameter-enlargement part were measured. In addition, the simulation analysis method in the processing was developed by the finite element method (FEM), the behaviors of stress and strain on processed part were analyzed, and deformation mechanism was investigated. It is clarified that the processing conditions affect the deformation behaviors base on the experiments and analysis.

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INVESTIGATION OF RELIABILITY OF THE SCREW UNIT OF THE COAL-ROLL PRESS BТ-3М

SERIES CHEMISTRY AND TECHNOLOGY ◽

10.32014/2020.2518-1491.32 ◽

2020 ◽

Vol 2 (440) ◽

pp. 120-128

Author(s):

E.S. Abdrakhmanov ◽

B.T. Yermagambet ◽

Zh.M. Kassenova ◽

M. K. Kazankapova ◽

А. Sairanbek

Keyword(s):

Stress State ◽

Screw Press ◽

Specific Pressure ◽

Equilibrium Equations ◽

Hollow Shaft ◽

Method Of Calculation ◽

Calculation Of Parameters ◽

Second Stage ◽

Blade Thickness ◽

Constant Section

In the article we propose the method of calculation of parameters of stress state and rigidity of screw blade at bending in one plane, screw-piston press of BТ-3М grade for production of coal briquettes is simultaneously mixing, transporting and pressing unit. The blade is regarded as a thin axially endless helicoid shell rigidly attached to the shaft along an internal helical boundary. Considering that the presence of the blade does not affect the deformation of the constant-section shaft during bending, we examine the effect of the presence of the blade on the bending stiffness of the screw. Invention covers the problem of screw blade deformations at preset displacements at inner boundary caused by shaft bending considering that its axis has curvature. In the second stage of calculation we construct a compensating solution, which eliminates inconsistencies in differential equilibrium equations and static boundary conditions, and on the inner contour of the shell we set conditions of rigid pinching. As a result, the screw was calculated using the developed method. Blade is calculated with parameters r1 = 0.04 m, r2 = 0.1 m, r3 = 0.03 m, screw blade thickness d = 0.005 m, L = 0.2 m, total length of hollow shaft 1, 2 m. Calculations have shown that at such screw parameters and created specific pressure of material on the screw Ore = 8.5 · 105 Pa, the rigidity of the blade is the stiffness 11% of the tubular shaft. Keywords: screw, press, calculation, briquette, extras, equations.

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Short Stress State Questionnaire

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000200 ◽

2015 ◽

Vol 31 (1) ◽

pp. 20-30 ◽

Cited By ~ 28

Author(s):

William S. Helton ◽

Katharina Näswall

Keyword(s):

Stress State ◽

Factor Structure ◽

Human Performance ◽

Self Report ◽

Confirmatory Factor ◽

Stress States ◽

Related Stress ◽

Using Data ◽

Task Conditions ◽

Multiple Samples

Conscious appraisals of stress, or stress states, are an important aspect of human performance. This article presents evidence supporting the validity and measurement characteristics of a short multidimensional self-report measure of stress state, the Short Stress State Questionnaire (SSSQ; Helton, 2004 ). The SSSQ measures task engagement, distress, and worry. A confirmatory factor analysis of the SSSQ using data pooled from multiple samples suggests the SSSQ does have a three factor structure and post-task changes are not due to changes in factor structure, but to mean level changes (state changes). In addition, the SSSQ demonstrates sensitivity to task stressors in line with hypotheses. Different task conditions elicited unique patterns of stress state on the three factors of the SSSQ in line with prior predictions. The 24-item SSSQ is a valid measure of stress state which may be useful to researchers interested in conscious appraisals of task-related stress.

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