INOXPA Double Seat Valve Mixproof Seat Lift

Application

The Mixproof valve is a completely hygienic double sealing valve. This system allows for the simultaneous processes in the two bodies of the valve by providing interface between the two fluids, preventing the possibility of product contamination. The leakage chamber and the leakage detector can be cleaned by the seat lifting system. Manifolding is one of the applications of these valves in the food-processing industries, especially in the beverage and dairy industries.

Operating principle

When the valve is open the fluid can pass from one body to the other. Once the valve is closed, the double seat creates an annular chamber that isolates the bodies sealing them with double seals. It allows a CIP operation providing an interface between the two fluids, preventing the possibility of product contamination. Due to the leakage detector any leak of a seat seal is detected by the  appearance of liquid at the bottom of the valve. The zone between the poppets and the seats is cleaned by pulsing the individual poppets when the specific line is being cleaned, the poppets are fractionally stroked by two additional limited movement pistons located within the main actuator. The valve is balanced providing protection against overpressure and hydraulic shock up to
30 bar.

 

Design and features

Compact design.
Valves with normally closed pneumatic actuator.
Weld connections (mm or inches).
Forged spherical bodies.
Balanced design.
Angular orientation 360ºC.
Open lantern allows visual inspection of the sealing.
Easy disassembly by releasing the clamp.
Available from DN 40 – 1 ½” to DN 100 – 4″.

Design and features

Parts in contact with the product                          AISI 316L
Other stainless steel parts                                      AISI 304
Gasket                                                                         EPDM in compliance with FDA 177.2600
Internal surface finish                                             Ra ≤ 0,8 μm

 

Operating principle

 

Valve closed

 

Lower poppet held closed by main spring.
Upper poppet held closed by Intermediate spring and product pressure.
Products protected by double seals.
Interspace open to atmosphere.

 

 

Valve open

Main piston raised by air pressure to main actuator connection.
Motion transmitted through central shaft to the lower poppet.
Lower poppet engages on upper poppet.
Leakage path to atmosphere closes.
Valve fully opens.

 

 

Upper Poppet Seat Clean

Lower piston pulsed by air pressure to bottom air connection.
Motion transmitted through outer shaft to the upper poppet.
Degree of lift controlled by central threaded adjustment.
Lower poppet positively held closed by main spring.
Fluid in upper body passes to atmosphere over poppet seal and through interspace.

 

 

Lower Poppet Seat Clean

Upper piston pulsed by air pressure to top air connection.
Motion transmitted through central shaft to the lower poppet.
Degree of movement controlled.
Pressure simultaneously applied above main piston.
Upper poppet positively held closed.
Fluid in lower body passes to atmosphere over poppet seal and through interspace.

 

Options

Gaskets: NBR and FPM.
Connections: DIN, SMS, Clamp, RJT, etc.
Conotrol box C-TOP.
Surface finish Ra ≤ 0,5 μm.
Mixed body sizes: combinations of bodies with different diameters.
DSO tank bottom valve.
Heating jacket.
Routing valve, with three bodies.

 

Technical specifications

General dimensions