The sterile access valve is one concept that over the years has attempted to improve the functionality of bioprocess systems.  While many advancements have come from valve manufacturers it is obvious that more can and should be done.  One common application is the sterile access port valve combination where a purge valve is required.

As can be seen by the rendering above, the so-called Sterile Access Valve creates a significant dead leg in the hygienic piping system. The Rattiinox  CAD valve (Clean Aseptic Design) diverting valve addresses this application in a novel way that eliminates dead-legs and improves overall functionality.  The design of the radial diaphragm valve satisfies industry demands for improved cleanability and sterilization by eliminating dead-legs and unused portions.  The CAD Divert valve greatly improves cleaning and sterilization by removing asymptotic dead-legs which are inherent in all weir style membrane valves.  Also eliminated is the purge valve dead-leg that is equal to the unused portion formed by one half of the valve.

One of the goals of the Rattiinox CAD aseptic valve range is to bring superior performance  to system design, especially if stainless steel systems are to compete with single use systems.  Why settle for poor hygienic design when a better solution is now available?

The CAD Divert valve can be configured in many ways to best fit the process requirements.

The Rattiinox CAD Diverting Valve is the new standard for Sterile Access Valves.  The CAD Diverting valve provides a way to safely steam sterilize a process loop.  The valve is also ideal by providing a port port for purging a process line as well as condensate draining.   The valve style can also be used for sampling however there are many other options from Rattiinox that may be more preferable.  The key but very important difference in the Rattiinox CAD valve diverting valve is the elimination of the significant dead-leg that is introduced into the piping system with other valve styles.  The CAD valve is also distinguished by a precision machined solid PTFE diaphragm that is not affected by CIP cleaning agents, steam, high sterilization temperatures and vacuum.

The valves are available with either butt-weld or sanitary tri-clamp ends.  The valve bodies are machined from bar stock and ASTM 1.4435 stainless steel is the typical body material.  Other higher alloys are also available.  The ASTM 1.4435 material has much less sulfur and ferrites than 316L material for higher corrosion resistance.

Eliminating the considerable dead-legs typically associated with these valves is important for every system but critical for down stream purification streams.  The dead-legs associated with other valve styles contributes to lower product recovery and difficulty reaching sterilization temperatures due to condensate build up.