Liquidyne® 2-Stage

LIQUIDYNE® 2-STAGE

The Liquidyne 2-Stage is the standard design of the Liquidyne range. This seal is used in pumps that process relatively clean media that may contain abrasive particles that are no larger than 100 µm.

Applications

Vertical sump pumps
Self-priming centrifugal pumps
Diffuser pumps
Booster pumps
Split case pumps
Concrete volute pumps
Vertical suspended pumps
Fish-friendly pumps

Advantages

Predictable lifetime due to condition monitoring
Low power consumption
Maximized maintenance intervals
Hard Metal Layer (HML) coating for extra durable grooved liners
No external flush needed
Optional design: can be designed with divisible housing parts

HOW IT WORKS

The Liquidyne 2-Stage design uses the process medium to lubricate, clean and cool the seal. The Liquidyne seal is made up of different modules and fulfils the following functions:

Sealing the pump shaft
Reducing pressure

The order of the modules can vary and depends on the specific application. The seal can be roughly divided into two parts:
A grooved shaft sleeve that is clamped and rotates with the pump shaft
The stationary housing parts and rubber lip seals that are mounted against the pump housing

The water-lubricated Liquidyne lip seals run over a partially grooved shaft sleeve placed over the pump shaft. The helical shape of the grooves and the peripheral speed (RPM) of the liner creates water flow (similar to aquaplaning) between the grooves and the lip seal. The water flows from the pump side to the drain of the seal. The condition of the seal is monitored by measuring the water flow from the pump side to the drain of the seal. The Liquidyne 2-Stage is available for shaft diameters from 35 to 590 millimetres.

PREDICTABLE LIFETIME

One of the main benefits of the Liquidyne is that the condition monitoring function is not just to simply monitor the condition of the seal, but it also creates a predictable lifetime. How? Over time, the grooves on the shaft sleeve gradually wear down. Less water is transported over the shaft sleeve and the amount of water leaving the drain decreases. When the drain flow is at 20% of the initial flow, maintenance needs to be planned.

By keeping track of this drain flow you can plan maintenance more efficiently, minimising the risk of sudden pump failure, optimise mean time between maintenance and reduce costs.

LIQUIDYNE® 2-STAGE

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