VARIVENT® Tank Bottom Valves

In general, the mixproof version is chosen when the tank is equipped with a single line for both filling and emptying. The mixproof valve makes it possible to clean the pipeline while the product in the tank undergoes the current process.

When the valve is closed (deactivated position), there are always two seals between the two media in the mixproof version. If a seal were to fail, any resulting leakage can be safely diverted from the leakage chamber to the valve’s periphery. This prevents the media from mixing between the tank and the pipeline.

There are various options for connecting VARIVENT® tank valves to the tank. Type T tank connections are used for installing valves on the bottom of the tank. Type U tank connections are preferred for horizontal installation of valves on the tank wall.

Simple tank shut-off valves are used when the tank is operated with separate fill and drain lines. It is not possible to clean the piping while the tank is in operation.

Mixproof tank shut-off valves are used when the tank is operated with shared fill and drain lines. The mixproof separation between the pipeline and the inside of the tank allows the pipeline to be cleaned while the process in the tank continues.

In the classic version, the mixproof tank shut-off valve isolates the process in the tank from the feed to the downstream valve matrix, which means that the tanks can be filled, emptied, and cleaned flexibly and in parallel with one another.

For some time now, mixproof tank bottom valves have been installed horizontally on a special connection unit directly beneath the tank (ECO-MATRIX™). In this case, the process lines do not converge in a valve matrix; instead, they are routed directly beneath the tanks to save space.

• The radial seal prevents coupling leakage and keeps the valve disc from vibrating under high pressure
• The balancer prevents the valve disc from closing too quickly when it closes in the direction of product flow, which reduces the risk of water hammer
• Thanks to the use of standard VARIVENT® actuators, this valve can be adapted to various process parameters
• In conjunction with the flush valve, the tank-bottom valve can also be installed horizontally, for example, in the new ECO-MATRIX piping concept

Lifting link (type T_RC, T_RL)

Type T_RC double-seat bottom valves are equipped with a lifting actuator that allows for the individual lifting of a single valve disc when cleaning the pipe or tank. The cleaning medium passes over the seal on the lifted valve disc, cleans the leakage chamber, and then flows out through the leakage outlet at the periphery. This makes it possible to clean all surfaces that come into contact with the product, including the surfaces of the valve disc seals.

Spray Cleaning (Type T_R, T_RL)

The valves have a cleaning connection at the level of the lantern, either as a separate connection (type T_R) or as an addition to the lifting device (type T_RL). Through this connection, cleaning fluid can be supplied to the leakage chamber from an external source. The chamber is then cleaned using an integrated spray nozzle, as a supplement to the cleaning performed by the lifting device.

The cleaning medium is then directed without pressure through the leakage outlet to the periphery of the valve. Cleaning takes place while the valve is closed, which means that the sealing contact surfaces are not touched during cleaning. In this way, the leakage chamber can be cleaned independently of the pipeline cleaning process. Furthermore, this allows for an intermediate flush before or after the valve is switched.

If the valves are equipped with both a lifting mechanism and the capability for external spray cleaning, the spray cleaning is used only for intermediate flushing during the individual switching cycles, while thorough cleaning is performed by lifting the valve disc.

Types T_R, T_RL, T_RC. For more information, see the catalog.