Mechanical seals
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Flowserve
Input for calculation of the seal face surface pressure P
G
Sealing pressure dp=p
1
-p
2,
(1bar = 0.1 MPa)
dp =
MPa
Balance ratio k=A
H
/A , (0.65<k<0.9, balanced k<1)
k =
Pressure gradient factor (parallel film k
1
=0.5)
k
1
=
Spring load / seal surface A (0.1<p
f
<0.5)
p
f
=
MPa
Input for calculation of leakage, viscous friction and power consumption
Seal face inner radius
r
i
=
m
Seal face outer radius
r
o
=
m
Number of revolutions
n =
rpm
Effective film thickness
h =
10
-6
m
Viscosity
η =
Pas
Surface pressure
p
G
=dp·(k-k
1
)+p
f
p
G
=
MPa
Leakage
Q =
liter/hour
Mean sliding velocity
v =
m/s
Coefficient of friction
µ =
Heat generation
N =
Watt
Symbols
A
Area seal face
[ m
2
]
A
H
Effective hydrostatic area
[ m
2
]
p
1
Medium pressure
[MPa]
p
2
Atmosphere pressure
[MPa ]
p
f
Ratio of spring load and seal face area
[MPa ]
p
G
Seal face surface pressure
[MPa ]
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