Aseptic Mix Proof Valves N7

The reliable separation of two process lines is achieved via the CIP/SIP capable leakage chamber of the RIEGER Mix Proof Valve N7 (also called double chamber valve). The CIP/SIP valves control the steam inlet and condensate outlet at the leakage space. The excellent aseptic properties are achieved by the hermetic separation of the ambient.

Rieger relies in the fruit sector e.g. yoghurt with strawberries not on the metal bellows, but on the PTFE-metal combi bellows which connects the durability of the PTFE bellows (more than 1 million cycles) with the erosion-free sealing technology of the O-ring!

This valve is indispensable in aseptic valve clusters and aseptic filling machines, in which the highest value is placed to comprehensive product safety.

Left picture: pipe version

Tank Version

Another variation is the aseptic double seat valve N7 (also called double chamber valve) as a tank discharge valve. Like in the version for pipe,the separation of product from the environment is completely guaranteed.
The PTFE bellows ensure due to their novel design extremely long shelf life (more than 1 million strokes). When opening the valve the folds are not on block, so that the folds always remain open and can be cleaned properly. Unlike metal bellows, which need for sealing O-rings, here the PTFE bellows is the only sealing element, that the valve interior from the environment hermetically seals without dome or dead space (one-piece gasket in contact with product).

Materialin contact with product
not in contact with product
GasketsPTFE bellows
metal bellows
 continuous operation

steam sterilization
130 °C*

150 °C*
121 °C*

135 °C* short-time
(approx. 20 min)
Pressuresclosing pressure
Type pipe
Type tank

control air pressure

max. 6 bar in the pipe
max. 4 bar in the tank

min 6 bar -
max. 10 bar
Surfacesin contact with product

not in contact with product
Ra ≤ 0,8 µm
other surfaces
on request
Ra ≤ 1,6 µm
pipe classes
DIN 11850-R2 (DIN 11866 A)
O.D.-Tube (DIN 11866 C)
DIN EN ISO 1127 (DIN 11866-B)


                                                                                 *dependent upon operating conditions
Aseptic Mix Proof Tank Outlet Valve N7
Port configurations as shown
in picture or in 360° possible.
Construction of the valve

massive valve housing

no dead spaces

completely draining

many possible installation orientations

Absolute product safety

perfect isolation from the environment
no sump, no dome


seal replacement without special tools

low downtime

screwed bellows

perfectly cleanable


long lifetime of PTFE bellows

standard seals

minimal maintenance costs

Additional certificates
in 3-A-design or with TA-Luft certificate
(the bottom seat valve) possible

This control top has been developed between AWH and Rieger in collaboration with Bürkert. It serves as a custom-fit solution for our in-house hygienic and aseptic process valves to achieve an even more efficient and precise application.

Contact-free inductive valve position measuring (Teach function)

  • status display luminated in colour
  • integrated control air supply to the actuator
  • field bus port AS-interface, DeviceNet, IO-Link or Bürkert system bus (büS)
  • with ATEX-option:
    Ex II 3 G Ex ec IIC T4 Gc X

    Ex II 3 D Ex tc IIIC T135°C Dc X

FlowStar is available in the models 24 V DC, AS-I bus, IO-Link (Port Class A) or Ethernet IP.
All models  are available as the following alternative:

  • 3 solenoid valves, 3 internal proximity switches + 1 outlet for external proximity switch

Mounting kit integrated in Control Top – no separate mounting kit necessary. Exception for LCV valves, ESV valves.

All Valves are available in special alloys, such as Hastelloy® C-22, 1.4539/904L, 1.4529, AL-6XN® and others.

Directly send us your inquiry:
Tel.: +49 7361 5702-0