Pumping Action of Aligned Smooth Face Seals Due to Axial Vibrations-Experiment

1986 ◽  
Vol 108 (1) ◽  
pp. 46-52
Author(s):  
M. Kaneta ◽  
M. Fukahori

The mechanism of pumping action caused by axially vibrating one of the seal faces with continuous parallel film thickness is clarified experimentally. The results obtained in the experiment confirm the theory developed in a previous investigation [11]. The fundamental design principles of mechanical seals are also described from the viewpoint of this pumping phenomenon.

1984 ◽  
Vol 106 (3) ◽  
pp. 344-351
Author(s):  
M. Kaneta ◽  
Y. Jinnouchi ◽  
M. Fukahori

This is an analytical study of the mechanism of pumping action produced in two axially symmetrical disks. The disks have a continuous parallel film thickness between them, and one of them has a recess at the center and is subjected to a normal sinusoidal oscillation. It is found out that whether the pumping action is inward or outward depends upon a shift of phase between a variation of flow resistance due to a periodic fluctuation of the film thickness between seal faces and a variation of pressure in the recess.


Author(s):  
Slawomir Blasiak

Noncontacting mechanical seals with various kinds of face surface modifications have established their position in the sealing technique. Over the last few years, a lot of works dedicated to the impact of various surface modifications on the dynamics of working rings have been created. This paper presents model studies regarding relatively unknown noncontacting impulse gas face seals. Here, a mathematical model of impulse gas face seals is developed including the nonlinear Reynolds equation and stator dynamics equations, which were solved simultaneously using numerical methods. An original computer software written in C + + language was developed. A number of numerical tests were conducted and the phenomena occurring in the radial gap during seal operation were analyzed. Final conclusions were drawn and several features were indicated characterizing impulse face seals. It should be emphasized that numerical research on this type of seals has not been published yet. The literature usually presents simplified models for the noncompressible medium, which can be solved with the use of analytical methods.


Author(s):  
P Eriksson ◽  
V Wikström ◽  
R Larsson

In a previous investigation, grease thickener fibres were tracked as they passed through an elastohydrodynamic (EHD) contact in pure rolling using interferometry in a standard ball-and-disc apparatus. In order to capture single thickener fibres, a high-speed video camera was used. Here, the experiments have been repeated introducing different amounts of side slip for different rolling speeds and a faster video camera capable of capturing 4500 frames/s. The contact was lubricated with a continuous supply of grease. Two greases, based on the same synthetic poly(α-olefin) but thickened with Li-12-OH and lithium complex soap respectively, were studied. It was observed that the thickener fibres were stretched both before entering the contact and as they passed through it. Fibres seem to avoid the minimum film thickness regions and, if they enter, the film is restored immediately after passage.


1986 ◽  
Vol 108 (1) ◽  
pp. 42-45 ◽  
Author(s):  
I. Green ◽  
I. Etsion

A kinematic model of mechanical face seals is presented. Two basic seal arrangements are considered: a flexibly mounted stator with antirotation locks, and a flexibly mounted rotor with positive drive devices. The equation of kinematic constraint is derived and presented in a simple form for all the possible types of antirotation or positive drive mechanisms found in practical seals. This simple form is then used to derive the dynamic moments acting on the flexibly mounted element of the seal.


2012 ◽  
Vol 33 (18) ◽  
pp. 5768-5788 ◽  
Author(s):  
Pontus Olofsson ◽  
Stephen V. Stehman ◽  
Curtis E. Woodcock ◽  
Damien Sulla-Menashe ◽  
Adam M. Sibley ◽  
...  

2017 ◽  
Vol 6 (10) ◽  
pp. 1851-1859 ◽  
Author(s):  
Ahmad A. Mannan ◽  
Di Liu ◽  
Fuzhong Zhang ◽  
Diego A. Oyarzún

2011 ◽  
Vol 133 (4) ◽  
Author(s):  
Christophe Minet ◽  
Noël Brunetière ◽  
Bernard Tournerie

Mechanical seals are commonly used in industrial applications. The main purpose of these components is to ensure the sealing of rotating shafts. Their optimal point of operation is obtained at the boundary between the mixed and hydrodynamic lubrication regimes. However, papers focused on this particular aspect in face seals are rather scarce compared with those dealing with other popular sealing devices. The present study thus proposes a numerical flow model of mixed lubrication in mechanical face seals. It achieves this by evaluating the influence of roughness on the performance of the seal. The choice of a deterministic approach has been made, this being justified by a review of the literature. A numerical model for the generation of random rough surfaces has been used prior to the flow model in order to give an accurate description of the surface roughness. The model takes cavitation effects into account and considers Hertzian asperity contact. Results for the model, including Stribeck curves, are presented as a function of the duty parameter.


Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1057
Author(s):  
Yin Luo ◽  
Yakun Fan ◽  
Yuejiang Han ◽  
Weqi Zhang ◽  
Emmanuel Acheaw

In order to explore the dynamic characteristics of the mechanical seal under different fault degrees, this paper selected the upstream pumping mechanical seal as the object of study. The research established the rotating ring-fluid film-stationary ring 3D model, which was built to analyze the fault mechanism. To study extrusion fault mechanism and characteristics, different dynamic parameters were used in the analysis process. Theoretical analysis, numerical simulation, and comparison were conducted to study the relationship between the fault degree and dynamic characteristics. It is the first time to research the dynamic characteristics of mechanical seals in the specific extrusion fault. This paper proved feasibility and effectiveness of the new analysis method. The fluid film thickness and dynamic characteristics could reflect the degree of the extrusion fault. Results show that the fluid film pressure fluctuation tends to be more intensive under the serious extrusion fault condition. The extrusion fault is more likely to occur when the fluid film thickness is too large or too small. Results illustrate the opening force is affected with the fluid film lubrication status and seal extrusion fault degrees. The fluid film stiffness would not always increase with the rotating speed growth. The seal fault would occur with the increasing of rotating speeds, and the leakage growth fluctuations could reflect the fault degree.


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