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Radial Diaphragm Tank-Bottom Outlet Valves

The Rattiinox CAD aseptic radial diaphragm tank-bottom outlet valve represents the latest advancements in both radial diaphragm valve and tank-bottom outlet valve design.  Rattiinox CAD (Clean and Aseptic Design) radial diaphragm valves have been engineered for use in the most demanding process applications.  The description varies but whether you describe your process as sanitary, high-purity, sterile or aseptic, your valves must be cleanable in place, sterilizable in place, reliable as well as easy and fast to service. Some of the typical applications for the CAD valves are in media preparation, fermentation, harvest, filtration including critical separation, concentration and purification steps.  Additional applications where the CAD valves are also ideal is high-purity water distribution loops, water and product sampling and of course tank-bottom outlet service.

Rattiinox CAD Tank-Bottom Outlet Valves
Rattiinox CAD Tank-Bottom Valve

The Rattiinox CAD radial diaphragm valves have a single body seal and are self-draining with no entrapment areas. Other valves are characterized by multiple body seals that risk the entrapment of stagnant product between the various seals.  Valves that have multiple seals increases the risk of process cross contamination and should be avoided at all costs.  The Rattiinox CAD valves have seals that are at 90° and fully open for easy, fast and perfect cleaning.  Other sanitary valves are designed with body closure as well as product path seals that have asymptotic angles that are hard to clean because of the reduced velocity in the ever decreasing angle.

Membrane Valve Asymptotic Seals
Membrane Valve Asymptotic Seals

The Rattiinox CAD valves fitted with the precision machined solid PTFE diaphragm have shown excellent service life, which in most cases is rated in years.  The unique design also allows removal of the diaphragm from the valve for inspection and re-installation without negative effects.  The CAD valve diaphragms can be changed very quickly and the reduced need to change diaphragms in the first place represents real maintenance cost savings!

Rattiinox CAD Tank-Bottom Outlet Valves
Rattiinox CAD Tank-Bottom Outlet Valve

It is well known that the clamping force for TC connections is not uniform. Unlike valves that use a clamp connection, the stainless steel seal ring on the Rattiinox CAD valve provides complete 360° pressure on the entire diaphragm. The Rattiinox CAD valves save maintenance down time as it can take less than a minute or two to change a diaphragm.  The valves feature a unique stop feature that prevents over tightening of the diaphragm.  The CAD valve is the first diaphragm valve (radial or membrane) to be engineered to use a solid PTFE diaphragm as the primary option.  Rattiinox CAD valves fitted with the standard PTFE diaphragm seal against pressures that far exceed standard bioprocess applications which increases your reliability safety margin.  Independent testing has purposefully stressed the CAD valves to pressures upwards of 90 bar and 0.92 bar vacuum with no leaks or ill-effects on the diaphragm.  This level of safety and reliability is simply not available from elastomeric based valves.

Rattiinox CAD Tank-Bottom Outlet Valves with Satalite valve with tangential outlet
Rattiinox CAD Tank-Bottom Outlet Valve with Satalite valve with tangential outlet

The Rattiinox CAD valves have been tested at temperatures above 160°C (320°F) for extended periods of time without damage.  Testing was performed with cycle times counted in seconds instead of minutes and the duration of testing lasting months instead of days.  In all cases the valve body and process seals hold 6 bar (90 psi).  Real word clients commonly report service life of the diaphragms in many cases over two years in high cycle process applications.  The Rattiinox CAD valve is a true flush bottom design and is highly adaptable to many challenging requirements.  The valves do not have a pocket or double body seals and are fully drainable.  As you would expect, the CAD tank-bottom outlet valve is generally welded flush to the bottom of the vessel. In other configurations the CAD tank-bottom valves can be flange mounted, welded into the knuckle of the tank or machined directly into the bottom dish.  And as you might also expect the Rattiinox CAD tank-bottom outlet valves can be ordered with a closed fitting satellite valve for cleaning and steaming behind the main diaphragm. These valves can have an eccentric outlet that eliminates the standard downward elbow for applications where the vessel bottom has limited clearance.

Rattiinox CAD Tank-Bottom Outlet Valves
Rattiinox CAD Tank-Bottom Outlet Valve

No matter your applications, the Rattiinox CAD valve has the ideal valve configuration to allow you to concentrate on other process issues instead of managing the maintenance of your valves.  Which is why we say the CAD valve is one valve with many solutions.