Shaft-hub-connection certified tight!

Since 2008 THALETEC offers the proven Multiflex technology for connecting stirrers and stirrer shafts as well as the CryoTec technology. With the CryoTec technology, the connection between the mixer and the mixer shaft is made by means of a shrink-fit connection: Turbine and shaft have high-precision machined cylindrical fitting surfaces.

To mount the agitator, the shaft is cooled down with the help of liquid nitrogen. This reduces the diameter of the fitting surface on the shaft by a few tenths of a millimeter. This is enough to be able to push the turbine onto the shaft. After the temperature of the shaft and the turbine has been equalized, the turbine sits firmly on the shaft and is "shrunk on". The connection is designed so that up to 8 times the motor torque can be safely transmitted.

Demonstrably tight!

The THALETEC CryoTec system is fully compatible with comparable connection systems of other manufacturers.

Based on a customer request, it has now been proven in a test that the CroyTec shaft-hub connection system is gas and liquid-tight.

Agitator, consisting of a shaft and turbines mounted on it. In this case, the turbine is a TAR residual volume turbine.

For this purpose, an experimental setup was manufactured: A turbine hub was shrunk onto the shaft. Then the connection was closed on one side and pressurized.

The pressure drop and leakage were observed. This test setup was deliberately chosen, although in real operation of glass lined CryoTec turbines, there is no pressure difference between the two sides of the hub.

With the help of this test it could be proven that the connection is tight (liquid-tight AND gas-tight) even at a pressure of at least 7 bar applied to one side.

The test result was also documented by a notified body, the "Testing and Certification Body of DEKRA (Certificate No.: 26864-1890817839-30400-421420).


THALETEC CryoTec shaft/hub connection for the connection of shafts and turbines are tight. Media do not penetrate the connection. At the same time, CryoTec connections are still fully compatible with other glass lined cylindrical shaft-hub connections, so that THALETEC CryoTec turbines and shafts can continue to be used to replace existing agitators from other manufacturers.

Leak test for a CryoTec connection