Aseptic Mix Proof Valves N7

e reliable separation of two process lines is achieved via the CIP/SIP capable leakage chamber of the RIEGER-double seat 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

Recommended Bürkert control tops for aseptic valves with 24 V DC or ASI bus
Contactless position with three switching points (teach-in function) with 3 internal feedback sensors, 1 output for external feedback (external feedback not included).

Two alternatives:

24 V DC with 4 digital outputs screw terminals, cable gland:

AS-Interface with a maximum of 62 slaves flat cable clamp with 1 m cable


  • 0 solenoid valve e.g. for single seat valves - pure feedback function
  • 1 solenoid valve for e.g. for single seat valves with actuators NC or NO
  • 2 solenoid valves for e.g. for single seat valves with air/air actuator or double seat valves N5, N9
  • 3 solenoid valves for e.g. double seat valves N1, N2, N3, N4, N7, N13

For more details see website Bürkert

All Valves are available in special alloys, such as Hastelloy C22, 1.4539/904L, 1.4529, AL6XN and others.

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