Liquidyne® 3-Stage Vacuum

LIQUIDYNE® 3-STAGE VACUUM

The Liquidyne 3-Stage Vacuum is specially designed for vertical pumps that start up dry. The vacuum allows the pump medium to hold a water column up to eight metres when the pump is at a standstill.

Advantages

Suitable for dry start-up of the pump
Retains pump medium up to eight metres
Predictable lifetime due to condition monitoring
Low power consumption
Maximised maintenance intervals
Hard Metal Layer (HML) coating for extra durable grooved liners
Optional design: can be designed with divisible housing parts

This seal is mainly applied to dredging pumps, sewage water pumps, booster pumps and mining pumps.

HOW IT WORKS

The vacuum module also prevents air leakage through the seal into the pump if the pressure inside the pump is lower than atmospheric pressure. The Liquidyne seal is made up of different modules and fulfils the following functions:

The Liquidyne seal is made up of different modules and fulfils the following functions:

Sealing the pump shaft
Reducing pressure
Holding a vacuum

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 Liquidyne 3-Stage Vacuum can be lubricated, cleaned and cooled with the pump medium if it doesn’t contain too many (up to 100 µm) abrasive particles. 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 peripheral speed (RPM) of the liner create 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 3-Stage Vacuum is available for shaft diameters from 35 to 510 millimetres.

MATERIALS

The Liquidyne 3-Stage Vacuum consists of a grooved shaft sleeve (stainless steel) with hard metal wear layer (HML), housing parts (bronze or stainless steel), NBR lip seals, Hastelloy^® C4 springs and a stainless steel clamping ring.

OPTIONAL

Low-pressure pumps can optionally use a liner with a smooth and flat surface instead of a grooved surface.

CUSTOMISATION

Are our standard solutions not suitable for your application? Our engineers are more than happy to develop a custom-made sealing product!

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® 3-STAGE VACUUM

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