Can the double mechanical seal of a centrifugal pump be replaced with a single mechanical seal? What considerations should be taken into account when making changes?
Thread Content
Can the double mechanical seal of a centrifugal pump be replaced with a single mechanical seal? What considerations should be taken into account when making changes?
Mechanically, there is absolutely no problem with this; we often make changes to the sealing design of some of our pumps.
Change from double-seal to single-seal, depending on whether the material permits such a change. Only materials that can serve as a flushing fluid on their own can be modified.
Double-sealing is generally used for highly hazardous media such as those that are toxic, harmful, flammable, or explosive; whereas single-sealing is the opposite case, so it is necessary to switch to single-sealing – this requires careful consideration.
With dual-machine sealing, materials can sometimes get mixed into the circulating water
Most operating conditions are acceptable. Some mechanical seals with double-end face structures perform poorly because they have a set of sealing surfaces whose leakage direction is aligned with the direction of centrifugal force
The circulating water is used to cool the isolation fluid (and in some cases, the bearing housings as well). The material that is pumped and the circulating water operate in two separate systems; it’s unlikely for the material to mix with the circulating water