Layout and function
3.4
Shaft seals
Only one of the following shaft seals can be used.
3.4.1
Mechanical seals
Mechanical seals have a function-related leak.
•
Single acting mechanical seal
•
Single acting, non-balanced mechanical seal
•
Double acting mechanical seal
•
Double acting, non-balanced mechanical seal
3.4.2
Auxiliary systems
Sealing systems
Only one of the following sealing systems can be used.
Quenching
When quenching, the pressure of the pumped medium is
greater than the pressure of the sealing medium. The seal
surfaces are lubricated by the pumped medium.
Examples of use:
•
Pumped media which reacts chemically with the air
•
Prevention of offensive odors
•
Cooling of seals
•
Protection from icing
Variant
Features of sealing
medium
With open
fl
ow
•
Supplied and drained
continuously
•
Unpressurized
In the closed system
•
Circulating in a closed
circuit
•
Unpressurized
Tab. 3
Quenching - variants and features
Blocking
When blocking, the pressure of the sealing medium is greater
than the pressure of the pumped medium. The seal surfaces
are lubricated by the sealing medium.
Examples of use:
•
Pumped media which crystallizes or contains solids and
therefore damages the seal in the long-term
•
Toxic conveyed media
•
Environmentally hazardous conveyed media
Variant
Features of sealing
medium
With open
fl
ow
•
Supplied and drained
continuously
•
Impinged with pressure
In the closed system
•
Circulating in a closed
circuit
•
Impinged with pressure
Tab. 4
Blocking - variants and features
300 486
BA-2015.12.16 EN
SHB
11
