Increasing fretting resistance of flexible element pack for rotary machine flexible coupling Part 1. Analysis of the reasons affecting fretting resistance of flexible elements for expansion couplings

Misalignment is one of the problems that often occurs in rotary equipment. In this paper, the observation was done to the rotary machine model in response to changes of axial misalignment by using vibration meter and infrared thermography camera. The model was a machine series, consisting of electric motor and disc which was connected by 3 Jaw flexible coupling. The shafts were positioned into several axial misalignment conditions to see the effect on the overall vibration value and its component temperature. The result of vibration observation showed that under certain conditions, by increasing shaft misalignment then the overall vibration value tends to decrease. With the decrease of overall vibration value, the machine condition was not in better condition. This was indicated by observing the temperature of the components in this condition, which showed the opposite fact. As misalignment increases, the temperature of the engine components also increases.

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Load simulation and substantiation of design values of a pin flexible coupling with a flexible disk-type element

Mining science and technology ◽

10.17073/2500-0632-2021-2-128-135 ◽

2021 ◽

Vol 6 (2) ◽

pp. 128-135

Author(s):

R. S. Melezhik ◽

D. A. Vlasenko

Keyword(s):

Computer Aided Design ◽

Operational Reliability ◽

Design System ◽

Mechanical Equipment ◽

Total Width ◽

Standard Size ◽

Flexible Coupling ◽

Flexible Element ◽

Flexible Disk ◽

The Given

In the process of operation of present-day mechanical equipment, dynamic loads arise, leading to the failure of parts, assemblies and mechanisms and, thus, reducing the equipment life time and operational reliability. A method has been developed for calculating the design and technological values of a pin flexible coupling with a flexible disk-type element, using the method of central compositional rotatable uniform planning of the second order and the finite-element method for calculating stresses using a computer-aided design system. The analytical dependence of the torque on the PCD (pin (centers of holes for pin) circle diameter) and the width of the flexible element with certain physical and mechanical properties was substantiated, on the basis of which the formula for the total width of the flexible disk-type element was obtained, taking into account the value of the required torque and the given PCD. In order to check the obtained dependence of the nominal torque, an additional study of couplings with the given PCD was carried out at different total width of the flexible element. The implemented research allowed determining the influence of the design characteristic values on the transmitted torque of a pin flexible coupling with a flexible disk-type element. A standard-size range of couplings with certain design and technological values has been proposed.

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Resonance of a rotary machine support beam considering geometric stiffness

Journal of Theoretical and Applied Mechanics ◽

10.15632/jtam-pl/126681 ◽

2020 ◽

Vol 58 (4) ◽

pp. 1023-1035

Author(s):

Alexandre Wahrhaftig ◽

Reyolando Brasil ◽

Thiago Groba ◽

Lauro Rocha ◽

José Balthazar ◽

...

Keyword(s):

Rotary Machine ◽

Geometric Stiffness

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INFLUENCE OF DICARBOXYLIC ACIDS ON SOWING QUALITY OF SPRING BARLEY

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2018/5/22-25 ◽

1970 ◽

pp. 22-25

Author(s):

N. N. Loy ◽

S. N. Gulina

Keyword(s):

Organic Acids ◽

Spring Barley ◽

Dose Range ◽

Dicarboxylic Acids ◽

Rotary Machine ◽

Working Solution ◽

Negative Effect ◽

Sprouted Seeds

The effect of presowing seed treatment on various concentrations of dicarboxylic (organic) acids on the sowing characteristics of spring barley has been studied. Seeds were treated with organic acids obtained by exposing cuttings to the radiation with a dose of 100 kGy and consequent hydrolysis, in concentrations: 1•10-7 %; 1•10-9; 1•10-11; 1•10-13 and 1•10-15 % on a laboratory rotary machine RVO-64 for one day before laying for germination. Distilled water was used for the control case. The rate of application of the working solution calculated as 10 liters / ton of seeds. Seeds were germinated in filter paper rolls in accordance with GOST 12038-84 requirements. The temperature was maintained at +24 ° C in the thermostat where the glasses with rolls were placed. For determination of germinative power and laboratory germination the sprouted seeds were evaluated after three and seven days, respectively. In laboratory experiments it was established that the treatment of barley seeds of varieties Zazersky 85, Nur and Vladimir with organic acids (OK) in different concentrations had both a stimulating and a negative effect. On the Zazersky 85 variety, in variants with acid concentrations of 1•10-9 and 1•10-11, an increase in germination energy (EP) by 2-4% and a significant decrease (by 3-4%) of laboratory germination (LV) of barley seeds were noted. On the Nur variety, the increase in EP was observed at 4% (concentration 1•10-11), LV and seed growth force (CPC) by 2-7% at a concentration of 1•10-7 and in the dose range 1•10-11 - 1•10-14 compared to the control values. On the grade of Vladimir, an increase in EP, LV, and CPC was found to increase by 1-6% at concentrations OK 1•10-7 and 1•10-13. It was shown that the treatment of seeds with acids led to an increase in the length of the germ in all studied varieties (by 3-9%) and dry biomass of 7-day-old seedlings - by 3-6%. Consequently, the treatment of seeds with a mixture of dicarboxylic acids has a stimulating effect on the sowing quality of spring barley.

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