top of page


SERVICEAVAAsset 10.png


Mixproof design

Many optional versions

Mixproof Shut-off Valves

VARIVENT® double-seat valves are used for mixproof shut-off of incompatible products at the pipe junctions. The structure of the VARIVENT® modular system means that many optional versions are available for adapting the valve optimally to the process.



When the valve is closed (non-actuated position), there are always two seals between the separated pipelines. If one seal is defective, the resulting leakage will be directed through the leakage outlet into the periphery, without mixing with the product in the second pipeline. This method enables that there is no mixing between the products from two pipelines.

Application Examples


To accommodate the different requirements of various industries, applications and processes, we offer mixproof shut-off valves of various technical configurations in our portfolio. 

VARIVENT® double-seat valves with spray cleaning of the leakage chamber are frequently used in non-critical areas:

Breweries: Cold process area, e.g. fermenting cellar
Dairies: Before heat treatment, e.g. milk reception, raw milk storage...

VARIVENT® long-stroke valves are used for transporting products with relatively large particles or for viscous products, such as yoghurt with pieces of fruit.

Special Features

  • Certified, hygienic configuration

  • Metallic stop

  • Flexibility because of the modular principle

  • Proven seal geometry

  • Mixproof separation

  • Availability of different valve configurations

  • Spray cleaning connection for cleaning the leakage chamber

Variety of Types


The different variants of the VARIVENT® double-seat valve make it possible to select valves that are optimally adapted to the process. 

The axial sealing valve types D and B entail a small switching leakage during each switching procedure, but they notably have a very long service life with the axial seals. 

The radial sealing valve type R offers the advantage of switching nearly without any switching leakage. 

Valve types B and R are additionally characterized by a balancer in the lower valve housing. This enables the valve to reliably remain in the closed position even if there are water hammers in the lower pipeline.

Valve type K represents a typical double-seat valve with two independent valve discs in which these two seals are located.

Valve type C, on the other hand, is a double-seal valve in which these two seals are together with the leakage chamber in between them in a valve disc.

In both versions, two seals prevent any mixture between a product line and a line carrying a cleaning media.

SERVICEAVAAsset 10.png
bottom of page