Failure of mechanical seals in centrifugal pumps

Author(s):  
Stan Shiels
2021 ◽  
Vol 1741 ◽  
pp. 012031
Author(s):  
T A Shihab ◽  
L S Shlapak ◽  
N S Namer ◽  
P M Prysyazhnyuk ◽  
O O Ivanov ◽  
...  

Author(s):  
David B. Stefanko ◽  
Robert A. Leishear

A reduction of radial vibrations in mechanical seals increases the life of the seals in centrifugal pumps. Mechanical seals consist of two smooth seal faces. One face is stationary with respect to the pump. The other rotates. Between the faces a fluid film evaporates as the fluid moves radially. Ideally, the film evaporates as it reaches the outer surface of the seal faces, thereby preventing leakage from the pump and effectively lubricating the two surfaces. Relative vibrations between the two surfaces affect the fluid film, damage the faces, and decrease the life of the seals. In a series of industrial applications, different techniques were used to minimize vibration, and the life of the seals was shown to significantly increase. The operating speed was controlled in one case, the bearing design was replaced in another case, and the stiffness of the pump was altered in still another case. The common corrective action in each case was a reduction in vibration.


Author(s):  
Robert A. Leishear ◽  
David B. Stefanko

A reduction of vibrations in mechanical seals increases the life of the seals in centrifugal pumps by minimizing fatigue damage. Mechanical seals consist of two smooth seal faces. One face is stationary with respect to the pump. The other rotates. Between the faces a fluid film evaporates as the fluid moves radially outward across the seal face. Ideally, the film evaporates as it reaches the outer surface of the seal faces, thereby preventing leakage from the pump and effectively lubricating the two surfaces. Relative vibrations between the two surfaces affect the fluid film and lead to stresses on the seal faces, which lead to fatigue damage. As the fluid film breaks down, impacts between the two seal faces create tensile stresses on the faces, which cycle at the speed of the motor rotation. These cyclic stresses provide the mechanism leading to fatigue crack growth. The magnitude of the stress is directly related to the rate of crack growth and time to failure of a seal. Related to the stress magnitude, vibration data is related to the life of mechanical seals in pumps.


2011 ◽  
Vol 474-476 ◽  
pp. 1283-1287
Author(s):  
Ying Jie Hao ◽  
Bo Qin Gu

A failure analysis of mechanical seals of centrifugal pumps was presented with fuzzy comprehensive evaluation method. Both failure probability and failure consequence were analyzed to evaluate the risk grade of the mechanical seals. The potential risk level of a mechanical seal was estimated by the application of risk matrix. The proposed fuzzy comprehensive evaluation method can be used to judge the reliability of mechanical seals and provide an important reference for the safe and stable operation of centrifugal pumps.


2004 ◽  
Vol 10 (1s) ◽  
pp. 23-24
Author(s):  
Yu.A. Sukach ◽  
◽  
L.F. Ivchenko ◽  
Ya.N. Ivanov ◽  
◽  
...  

Sign in / Sign up

Export Citation Format

Share Document